C H A P T E R N O . 1C H A P T E R N O . 1C H A P T E R N O . 1C H A P T E R N O . 1

1.1) Concepts of coordination chemistry.

Modern concept of coordination compounds is the basis of most exciting

and active chemical research. Metal ions present in human body are in the form of

complex and coordination compounds. Metals can form many coordination

compounds and as catalysts they often play vital role in the living systems. Some

of them are extremely stable where as others are quite unstable, and many of them

have quite different colors from their constituents. Some compounds are readily

soluble in water and others are soluble only in non polar solvents, some of them

are volatile where as others are not. It is possible to build any of the desirable

property in to coordination compounds by proper tailoring of synthetic roots1.

Coordination compounds can be formed by the proper reaction of central

metal ion or cation and two or more molecules or ions referred to as ligands. Non

metal of the ligand donates electron pair (Lewis base) and metal ion accepts

electron pair (Lewis acid) in unoccupied orbitals. The ligand in a complex is said

to be coordinated to the atom that is present in a centre of new structure. Any

neutral compound that contains a metal atom and is surrounded by the ligands is

called coordination compounds. Such compounds may be formed between a

complex ion and other ions or the complex itself may be neutral. The number of

ligands bounded to central metal atom is equal to coordination number of that

metal. Coordination number of the central metal ion and number of ligands

1

attached to it will determine the geometry of the complex. Thus in complexes with

coordination number six, ligands will be usually directed towards the corners of

the octahedron and shape of the complex will be octahedral. Arrangement of

coordinating groups around the central atom is indicated by the polyhedral

symbols and is used as a prefix enclosed in parenthesis separated from the name

by hyphen; the polyhedral symbols for coordination geometries 2 to 9 are well

known2.

Square planar and octahedral complexes of the multi-dentate ligand exhibit

geometrical / stereo- isomerism which in also referred to as cis-trans isomerism.

In such complexes ligands may occupy different sites or positions around central

metal ion, either adjacent to one another or opposite to each other. Such

arrangement gives rise to specific activity to metal complexes . Complexes

having asymmetric atom exhibit optical isomerism i.e. they can exist in two forms

which are mirror images of each other. Geometrical or cis-trans isomers are

distinguished by, powder X-ray structure study, infra-red technique, resolution of

‘d’ and ‘l’ forms, intra molecular changes during reaction, absorption spectra,

Kurnakov reaction, Grinberg’s method3.

Complexes with more than one central metal ion are also known and are

called as polynuclear complexes. Such complexes are formed due to the fact that

a multi-dentate ligand bounded to one metal ion still has ability to donate another

lone pair of electrons. This is possible when number of donor groups exceeds

2

maximum coordination number of central metal ion or sterric arrangement of the

donor atom of the multi-dentate ligand does not make possible for all the donor

atoms to be coordinated to the same central metal ion. Such complexes are of

interest in several areas like multi-metallic enzymes, homogeneous and

heterogeneous catalysis. These complexes are justified by their structural diversity

and potential applications as functional materials in magnetism, molecular and

light conversion devices and in medicine. They may be homoatomic or

heteroatomic polynuclear type of complexes4.

In multi-dentate ligand, two or more unshared electron pairs present are if

not too close or not far apart from each other, they may coordinate to the same

metal atom to form a ring. Such phenomenon of ring formation by ligands in a

complex is said to be as chelation and ring so formed is called chelate. Chelates

with five or six member rings are much less strained and are very common.

Chelation greatly increases stability of a complex which is of tremendous

importance in altering properties of metal ions by complexation. Chelating agents

are also known as sequestering agents and have many potential applications5.

Derivatives of cyclopentadienyl such as Ferrocene, Cobaltocene and

Ruthenocene were also considered to be coordination compounds even though they

do not fit for the definition of coordination compounds. These compounds have

ability to undergo variety of substitution reactions to produce large number of

compounds. Now it is well established that metallocenes are the compounds where

3

metal atom lies between the two organic rings to form sandwich and is not bonded

to any of the specific carbon atom.

Compounds containing metal-metal bonds are known and metals in such

compounds are bonded to each other in many ways. Such compounds are

referred to as metal cluster compounds where metal atoms are connected by

covalent bonds6.

Transition metal ions, which have unparalleled tendency to form

complexes possess empty or incompletely filled ‘d’ orbitals that are not involved

in π- bond formation are regarded as hard acids where as metal ions with nearly

filled ‘d’ orbitals can form π-bonds with ligands by accepting electron pairs in

their empty ‘d’ orbitals. Such metal ions are regarded as soft acids. The charge

and size of the metal ion determines many properties of the resulting complex.

Strong tendency of transition metals to form good number of complexes is

due to their smaller size and higher charge with vacant low energy ‘d’ orbitals that

can accommodate lone pair of electrons donated by ligands. Transition metal ion

with (III) oxidation state, generally form stable complexes than those with (II)

oxidation state. Weak ligand can form complexes with transition metal ions in

either zero or lower oxidation state while strongly basic ligands yield stable

complex with metal ions in higher oxidation state7.

4

Most of the transition metal ions form colored complexes, which arises

mainly due to transition of electron form lower energy ‘d’ orbitals to higher energy

‘d’ orbitals. Ligands attached to central metal ion alter the energy of d orbitals and

destroy their degeneracy whereby they are separated into t2g and eg groups of

different energy. Thus central metal ion with partially filled‘d’-orbital can promote

electron from lower energy to higher energy ‘d’orbital. This corresponds to very

small energy difference and light is absorbed in visible region. Color of transition

metal complex is dependent on this energy difference between t2g and eg orbitals

and in turn depends on the nature of ligand and type of complex formed. Color

changes with nature and number of ligands and depends on type of complex

formed. Complexes where d-d transition is not possible are colorless. Oxo-anions

of the transition metals exhibit color due to charge transfer from oxygen to metal

ions. Since charge transfer occurs between the two atoms that have energy levels

fairly close, it produces intense color. Laporte and spin selection rules are not

applied for such transition8-9

.

Transition metal complexes generally possess partially filled ‘d’ orbitals;

change in magnetic properties would be expected depending upon oxidation state,

electronic arrangement and coordination number of central metal ion complexes are

classified as diamagnetic or paramagnetic depending upon their behavior in

presence of strong external magnetic field. Diamagnetic complexes produce

magnetic moments due to induced circulation of electrons aligned in opposition to

5

the magnetic field. This happens if paired electrons are present within a sample.

Presence of unpaired electrons in the complex gives rise to paramagnetism. Spin

and orbital motion of these unpaired electrons produces permanent magnetic

moments that align themselves within the applied field.

Paramagnetism is observed in presence of external field, when field is

removed individual molecular moments are randomized by thermal motion and the

bulk sample has no overall magnetic moments. In presence of magnetic field there

will be a competition between thermal tendency towards randomness and field

capacity to force for alignment. Consequently paramagnetic effect decreases in

magnitude as temperature is raised. The unpaired electrons in the complex

produces magnetic field because of its spin and also because of it orbital angular

momentum. Thus additional and complimentary information on metal complexes

can be obtained from magneto chemistry 10-11

.

1.2) Biochemical aspects of transition metal chelates.

A variety of applications of coordination compounds ranging from

analytical chemistry to biotechnology and biochemistry are very impressive.

Some of the examples are in electroplating, metallurgy, photography, as dyes in

textile industry, in synthetic organic chemistry and as pharmaceutical drugs. In

qualitative and quantitative analysis, metal indicators, as masking agents, as

antidotes, in extraction of metals from minerals and in solvent extraction.

6

Applications complexing agents particularly depend upon their ability to dissolve

selectively, to tie up with metal ions and the ease with which metal ions removed

form solution. Removal of magnesium, calcium and iron form hard water by

complexing with tripolyphosphates is well known practice. EDTA is added to

food stuff to tie up metals that would spoil it12

.

Transition metal ions function as catalyst by temporary formation of

coordinate covalent bonds with ligands which undergoes reaction and subsequent

dissociation to restore the catalyst. In analytical chemistry an ion that would

interfere with the analysis is held in solution as complex while other ions are

detected and removed as precipitates. In well-known complexometric titrations,

where complexing agent is titrated with metal ion and end point is detected.

Humic acid formed in the soil by the decay of organic matter binds metal

ions, transport them through the soil and make available to the plant roots. Since

metal ions applied in the form of salts are not absorbed by the plant roots,

commercially available fertilizers containing chelated metal ion can be

conveniently applied as they stay in solution and can be absorbed easily.

Several transition metals are essential to living being in small quantity but

become toxic in larger amounts. They are complexed with proteins in metallo-

enzymes and catalyze crucial body functions. Most of the metal enzymes are

involved in chemical and energy transfer reactions. Energy release processes in

living systems are basically inorganic reactions mediated and made possible by

biochemical system13

.

7

Chromium and molybdenum are necessary in trace amounts in the diet for

healthy growth of mammals. Chromium is found to involve in maintaining

glucose level in the blood along with insulin. Manganese is essential part of

animal and plant enzymes as it is involved in conversion of nitrogenous waste into

urea in ornithiene arginine - citrulline cycle. Iron is most important element in

biological systems, in hemoglobin it functions as oxygen carrier, in myoglobin as

oxygen storage, in cytochromes and feridoxins as electron carrier, ferritene and

transferrin act as ‘Fe’ scavengers. Cobalt is an essential part of the Corrine ring of

vitamin B12. Copper is found to play a vital role in elasticity of aortic walls, brain

function, skin pigmentation and iron metabolism. Wilson’s disease is a result of

copper accumulation in liver. There are several blue proteins like plastocyanine

and azurine containing copper responsible for electron transfer in plants and in

bacteria respectively. Zinc is present in twenty enzymes of biological system. It

is found to play an important role in respiration, energy release, sugar metabolism

and in alcohol metabolism.

Besides these, number of undesirable compounds produced in the body

such as adrenaline, citric acid and cortisones which can form complexes with

metals like lead, cadmium, copper and prevent normal body function. Metal

toxicity can be minimized by injecting suitable chelating agent that forms a stable

complex and excreted through urine. Elimination of radioactive element from the

body can also be efficiently made by treatment of chelating agents14

.

8

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1.3) Methods for studying metal complexes : -

a) Physical methods: - The first inference of complex formation is by

preparation of a solid compound having different color and physical and

chemical properties from those of starting compounds. This method is

most commonly used till today. Freezing point, a colligative property,

depends upon the number of particles present in solution. Complex

formation is associated with decrease in the particles. Thus depression in

freezing point is an indicative of a complex formation. An increase in the

solubility of sparingly soluble salt produced provides a definite indication

that one of the ion forms a complex ion in solution. When metal ion

combines with ligands to form a complex there will be a decrease in ionic

activity of the metal which in turn increases the oxidation potential of the

system. E.M.F of the cell which depends upon nature of ions present in the

system. When complex ions are formed profound change in E.M.F. will

be observed. Conductivity of electrolytic solution changes with

concentration of solute and number of charges on the species.

Considering molar conductivities, concentration factor can be neglected

and conductivity depends only on total number of charges on species

formed when complex is dissolved in solvent. Comparison of molar

conductivities of the complexes with those of simple salts one can deduce

the number of charges presents. Thus molar conductivities suggest

9

probable charged particles in the complex formed. Dipole moment also

yields structural information for non-ionic complexes. It gives information

about cis and trans forms of the complex. In trans configuration metal-

ligand bond cancels out dipole moment where as cis arrangement of a

complex gives rise to finite dipole moment15

.

b) Chemical methods: - Formation of a complex is established by

disappearance of usual chemical properties of the metal ions in solution.

If a metal ion forms complex it losses some of its chemical properties in

the solution and is a definite evidence that the metal ion is present in form

of stable complex, ultimately concentration of simple metal ion in solution

is decreased. Majority of the ligands are either weak acids or weak bases,

formation of complex is always accompanied by displacement of one or

more acidic portions of the ligand by metal ion resulting in increase of H+

ion concentration and causing drop in PH. Thus measurement of P

H can be

used for detection of the complex formation. Metal ion gets distributed

itself into one of the two immiscible phases on complex formation.

Measurement of partition coefficient of the metal ion between two phases

also gives useful information about the complex formed. Measurement of

magnetic moments and magnetic susceptibility provides information about

the number of unpaired electrons present in a complex form this it is

possible to deduce how electron are arranged and orbitals they occupied

9

which in turn helps to draw probable structure of the complex. Ion

exchange method is more convenient for complexes having different

charge from that of corresponding metal ions. Anionic resin will absorb

only negatively charged complex ion but not metal ion itself. Thus

measurement of metal ion concentration in resin and in aqueous phase

provides information about the complex ion. Important and useful

information can also be obtained from polarographic measurements from

which coordination number and stability constant of the complex can be

determined. Shift in half wave potential of the metal ion when it is

bonded to ligand is the basis of this method. Amperometric study which

involves measurement of currents of constant voltage at the dropping

mercury electrode. The electrode potential for a selected metal ion being

reduced, current decreases with increase in ligand concentration and

attains a constant minimum value. From ligand concentration at minimum

constant current, metal to ligand ratio can be determined. Electrophoresis

and electro dialysis may also be used to detect complex formation where

the complex ion has negative charge. Such negatively charged colored

complex ion will migrate towards cathode. Lastly, transport number of an

ion that depends upon size and nature of ions. On complex ion formation

size of the ions increases where as number of ion decreases. Presence of

ionic species and charges can be detected by this method16

.

10

c) Spectral methods: - UV-visible absorption and electronic spectra of

metal complexes depend upon electronic transitions and on the strength of

metal ligand bond. Intensity of color produced by d-d transitions depends

upon nature of ligands attached to it. There will be an increase in intensity

of absorption and its shift to higher energy. Such shifts are observed when

coordinated water molecules are replaced by ligands that are more basic

than water molecules. This study is suitable for quantitative approach to

metal complexes . Infrared spectral study is based upon the simple fact

that a chemical substance shows marked selective absorption in the infra

red region. After absorption of IR radiations, molecules vibrate at many

rates of vibration, giving rise to closed pack absorption bands called IR

absorption spectrum, which may extend over a wide range of wavelength.

Various bands observed in IR spectrum corresponds to the characteristic

functional groups and bonds present in the chemical substance. Thus an IR

spectrum of substance is a fingerprint for its identification. IR

spectroscopy has been used by chemists for i) identification of compounds

ii) determination of purity iii) quantitative estimations and iv) structure

determination. Molecules that have unpaired electrons undergo transitions

between different states when placed in a magnetic field. N.M.R. method

is limited to the nuclei having resultant nuclear spins. Transitions will

occur between different energy states of the nucleus by the absorption of

frequencies when nucleus is placed in strong magnetic field. These

11

transitions are affected by the presence of unpaired electrons in the

orbitals of the molecules which may be utilized for measurement of

magnetic moments. The shift in proton N.M.R absorption called chemical

shift is a direct proof of complex formation. This method can also be used

even when there is no change in number of unpaired electrons of the

central metal ion on complexation. metal complexes can show absorption

in microwave region yielding electron paramagnetic resonance spectra,

EPR spectral measurements give value of magnetic moments and sub-

bands in the absorption bands that have been utilized to explain metal-

ligand bonding. The unpaired electrons being delocalized over the ligand

are in a different environment produce difference in energy of absorption.

This study can be carried out with very small amount of sample and can

give accurate information about the magnetic moments. From gyrometric

ratio ‘g’ values of transition metal complexes , important information

about structure of the complex can be derived. The information obtained is

used for studying complex formation even if there is no change in number

of unpaired electrons of the central metal ion17, 18

.

d) Other methods:-- Methods of thermal analysis are based on physico-

chemical changes of substance on variation of temperature. when it is

based on observation of weight changes as a function of temperature or

time, the method is referred to as thermo-gravimetry (TGA) and if the

12

measurement of difference in heat content of the sample with reference to

a standard substance as a function of temperature or time, it will be treated

as differential thermal analysis (DTA).Both TGA and DTA are widely

used in chemical analysis obtaining thermodynamic and kinetic data.

Kinetics of solid state reactions is elucidated to large extent using this

method. There are many reviews on applications of thermo-analytical

methods to derive parameters such as rate constant, energy of activation,

order of reaction and frequency factors. Thermal analysis of the

complexes can be carried out at a linear heating rate of 100 min

-1 in a

nitrogen atmosphere. Loss of water molecules, decompositions of organic

moiety and weight loss due to chlorides and coordinated atoms followed

by the formation of metal oxide would be deduced. Powder X-Ray

Analysis is one of the most powerful tools used for determination of

crystal structure. This will provide detailed information about the exact

shape, bond length and bond angles of the atoms in a structure of metal

complexes . The Bragg’s equation n λ= 2d sinθ where n is an integer from

this the number of planes are found at which the reflections will be

maximum, θ = sin-1

(λ / 2d) The study of the intensity of X- ray spectra

gives the required information about the arrangement of planes of different

atoms in space lattice. Lattice constant is given by the ratio of λ / d. The

crystal lattice may be regarded as a set of parallel planes passing through

the lattice points which are known as lattice planes. The lattice planes can

13

be chosen in different ways. The three numbers (h,k,l) designate a plane in

a crystal known as miller indices. From X-ray studies it is possible to

elucidate the structure of a crystal of given type of compound by the

limiting radius ratio. Percent porosity of the sample can be determined

from X-ray density and density of the samples by KBr palate method. Unit

cell volumes of the samples can also be calculated for various crystal

systems. For Tetragonal system V = a2c, Monoclinic system V = abc sin β,

Orthorhombic V = abc, where a, b, c and β are lattice parameters19

.

1.4) Literature review of Transition metal complexes :

In the last few decades there is renewed interest in synthesis and

characterization of transition metal chelates20

because of their diversified

applications in field of medicine, biotechnology, nano-technology and biological

sciences21-24

. Researchers at global level are involved in isolating and

characterizing solid complexes of transition metals with biologically active

chelating agents25-27

. Number of transition metal complexes of active

pharmaceutical drugs have been reported. Such newly synthesized transition metal

chelates are found to possess important technological and biological

applications28

. Copper complexes of antibacterial drug sparfloxacin and nitrogen

donor heterocyclic ligands were synthesized and reported29

. Manganese and cobalt

complexes of antibiotic sodium monensin have also reported30

. Several types of

cysteine derivatives like Penicillamine can form soluble complexes and have been

14

suggested as detoxification agents. For understanding the detoxification of

mercury in physiological systems structural studies on strong interaction of thiol

group of cysteine with mercury (II) complex can serve as model31

. Complexation

studies of Nalidixic acid and Norfloxacin with metal ions like Cu(II), Ni(II),

Zn(II), Co(II) and Hg(II) have also been reported32

.Iron Dopamine complexes

were synthesized and etiology as well as pathogenesis study of parkinsonian

disease was also reported. Dopamine hydrochloride and various ancillary ligands

have been studied as a function of PH in aqueous solution to determine optimum

PH for complex formation

33.

Transition metal complexes of thiosemicarbazone are evaluated to prove

good anticancer activity on cisplatin resistant neuroblastoma cells and exhibit a

great variety of biological activity34

. They have been also used for analytical

determination of metals35

.DNA interactions of copper thiosemicazone complex

and nature of binding in these complexes was also studied36

.Various transition

metal complexes from thiosemicarbazone derivatives have been isolated and

reported to be more active, especially chloro complexes in cis configuration

against gram negative bacteria37

.Copper complexes of substituted 8-hydroxy

quinoline thiosemicarbazide are proved to possess strong anticancer

activity38

.Cu(II), Ni(II), Co(II) and Fe(II) complexes of Oxime-thiosemicarbazone

were synthesized and evaluated to exhibit enhanced nuclease activity in presence

of oxidant39

. Transition metal complexes of thiosemicarbazides can play vital role

15

in the development of coordination chemistry. Besides having good complexing

ability, they are biologically active pharmacopores40

.Such biologically significant

potential transition metal complexes of Benzyl Napthofuran Semicarbozone are

reported recently41

. Nickel(II) complexes of 2-substituted-benzaldehyde-semi-

carboazones and thiosemicarbazones have been synthesized and characterized.

Ligand was found to coordinate with metal ion through carbonyl group of thioketo

and azomethine nitrogen. Complexes formed were reported to be of high spin

configuration on the basis of magnetic moment measurements42

. Transition metal

complexes of Oxime, Semicarbazone and phenylhydrazone were also prepared

and reported to exhibit satisfactory antibacterial activity43

.The structures and

spectroscopic properties of Hg(II)and Cu(II) complexes with

dialkyldithiocarbamate ligands were studied in solid state by C13

, NMR, XRD and

ESR spectroscopy. Binuclear mercury complex was centrosymetric; the central

tricyclic fragment was in chair confirmation, ESR data of Cu(II) complex indicates

magnetically diluted system mainly found in heterobinuclear molecules and

geometry approximated to tetragonal pyramid44

.

Coordination chemistry of transition metal complexes of Schiff bases

have also been widely studied due to their unusual magnetic properties, novel

structural features and relevance to biological systems45

. A study on the magnetic

exchange behavior in polynuclear complexes to design well characterized

compounds is a topic of current focus in magneto chemistry. This study was

16

followed by Cu(II) complexes of Schiff’ bases having µ3-OH core46

. Schiff base

metal complexes derived from 2-hydroxy-5-chloroacetophenone have been

synthesized, Cu(II), Zn(II) and Cd(II) complexes are reported to be more active

while Mn(II), Fe(II) and Ni(II) complexes less active against microorganisms47

. In

another study Schiff base derivatives of substituted 4-amino-5-mercapto-1,2,4-

triazoles were prepared and used to synthesize Cu(II), Ni(II) and Co(II)

complexes, these complexes were characterized by IR, 1HNMR, ESR and

electronic spectra48

. A series of Mn(II) and Cu(II) complexes of O-phynylene

dimine derivatives and their antifungal activity is also reported49

.Co(II), Ni(II)

and Cu(II) complexes of Schiff bases obtained from condensation of 2-amino-

chlorophenol/isoniazide/3,4-dichloroaniline with 2-hydroxy-acetophenone/

methyl-isobutyl-ketone/ 4-methylamino-benzaldehyde have been synthesized and

characterized by spectral methods. Complexes were indicated coordination

number 4, 5 and 6, reactivity of these complexes against some of the inorganic

ions / molecules has also been studied50

.Schiff base derived feroin condensation of

1, 2–diamino-butane with isonitro-p-methoxy chloroacetophenone was used in

synthesis of transition metal complexes . Ligand was coordinated to the metal

through oxygen atom of Oxime group. On the basis of 1HNMR and IR spectra

distorted square planar geometry was proposed for the complexes51

. Cobalt(II)

Salen complex has been tested for catalytic epoxidation of styrene with molecular

oxygen. Catalytic activities were found to be dependent on both electron effects of

the substitutents and presence of phenyl substitutents on ethylene moiety. Highest

17

activity was reached with bromine-substituted complex. Effects of temperature,

time and solvent were additive to catalytic activity52

. 3D-transition metal

complexes with Schiff bases derived from nitrobenzylidine were also isolated.

Physicochemical and structural elucidations have been done on the basis of micro

analytical data and spectral studies. Ligand field parameters of the complexes were

also reported53

.

Transition metal complexes of tridentate Schiff bases derived from 5-(2'-

thiozolylazo)-salicyldehyde were synthesized and copper complex was

characterized by ESR spectra and thermo-gravimetric analysis54

. Polymeric

complexes of metals with Schiff bases derived from hydroquinone and aromatic

aldehydes are reported to possess octahedral geometry where as complexes

prepared from Schiff base derivatives of salicyldehyde and anthranilic acid

reported to have square planar geometry55

. metal complexes of Schiff bases

obtained from p-benzyloxy aniline with 2,4-dihydroxy benzaldehyde have been

reported to be of non electrolytic nature. Ligand was coordinated through N and O

atoms. Square planar geometry was suggested on the basis of structural

investigations56

.Urea Schiff base metal chelates of chromium and titanium were

also isolated and on the basis of ESR spectra octahedral structure was proposed 57

.

On the other hand 4-4′-diaminodibenzyl substituted with salicyldehydes has been

used to prepare manganese and oxovanadium complexes58

. Schiff base transition

metal complexes derived from 5-nitrosalicylaldehyde and anthranilic acid were

18

also synthesized and characterized by X-ray diffraction studies59

.Cu(II), Cd(II) and

Hg(II) complexes with Schiff base derived from 1,2-diaminoethane and 1,4-

diamobutane were also reported and characterized by NMR, IR and mass spectral

studies60

. Cobalt(II) complexes of Schiff bases derived from p-hydroxy

benzaldehyde and 2-amino-6-methyl pyridine have been prepared and

characterized. On the basis of spectral studies distorted octahedral structure was

proposed for these complexes61

. Transition metal complexes of Schiff’s bases

derived from coumarin and amino phenol / amino benzoic acid have been reported

to be of non electrolytic nature. Physico chemical and spectral analysis indicated

octahedral geometry of the complexes where as ESR spectra of copper complex

revealed considerable exchange interactions among copper ions62

.

Pyridyl-bis-(imides) and pyridine bis-(imines) complexes of cobalt(II) and

iron(II) were synthesized and used as catalyst in polymerization of ethylene and

propylene63

. Transition metal complexes of mono, bi and trinuclear type were

successfully synthesized from Schiff base derived by condensation of pyridine

dicarboxaldehyde and 8-aminoquinoline64

. Mono nuclear metal complexes of

tetradentale N3O Schiff base have also been synthesized, characterized

spectroscopically and reported recently65

. Tridentate Schiff bases synthesized from

condensation of glycyl-glycine and indole-3-carboxyldehyde has been used to

prepare transition metal complexes . Electronic spectra of the complexes revealed

tetrahedral geometry to cobalt and nickel complexes where as square planar for

19

copper complexes66

.Schiff base derived from benzyloxyaniline with dihydroxy-

benzaldehyde have also evaluated to exhibit moderate antibacterial and antifungal

activities67

. metal complexes with Schiff base derived from 2-furyl and 2-amino-

6-methyl-pyridine have been isolated and studied. Formulation and structural

studies were followed by physicochemical and spectral methods. All the

complexes were reported to have octahedral geometry68

. Cobalt (II) complexes of

Schiff bases derived from p-hydroxy benzaldehyde and 2-amino-6-methyl

pyridine have been prepared and characterized. On the basis of spectral studies

distorted octahedral structure was proposed for these complexes69

. NI(II) and

Co(II) complexes of Schiff base obtained from orthophenylene-bis-

(Orthobenzoquinone-monooxime) have been isolated in alcoholic medium. From

spectral features along with electronic spectra and magnetic moment, metal

complexes were assigned octahedral geometry with some amount of

distortion70

.Benzofuran derivatives like Benzofuran-2-carbohydrazide Schiff bases

have been used to synthesize transition metal complexes . ESR spectra indicated

distorted octahedral environment around Cu(II) ions71

. Schiff base metal

complexes derived from benzyloxyaniline and dihydroxy-benzaldehyde have also

evaluated to exhibit moderate antibacterial and antifungal activities72

.Non

electrolytic and paramagnetic complexes of transition metals with Schiff’s base

derived from 5-nitro-salicyldehyde and p-anisidine were also reported to possess

monoclinic system with tetrahedral geometry73

.

20

Structural diversity of carboxylate complexes with transition metal ions

is well recognized. Pyridine carboxylates and other derivatives of pyridine has

been the subject of extensive investigations because of their biological role and

potential antineoplastic and antituberculosis activity74

. Diorganotin complexes

with 2,6-pyridine dicarboxylic acid were synthesized and reported to have

pentagonal bipyramidal structure on the basis X-ray studies75

. Manganese

complexes with 2-mercaptonicotinic acid formed multidimensional network

confirming multifunctional role of ligand in the complex76

. Nickel(II) complex

from pyridine derivative was synthesized and reported to possess distorted

octahedral structure and exist in form of dimer77

. Pyridine and malonic acid in

combination were used to prepare mixed ligand complexes and suggested

tetrahedral geometry for these mixed ligand complexes78

.Cobalt (II) chrotonates

and cobalt(II) adipates have also been synthesized and characterized. These

complexes were employed in dehydration of Hantzsch 2,-dimethyl,3-5-

dicarboethoxy,-1,4-dihydropyridine.79

Macrocyclic zinc complexes of ligand

derived from pyridine derivatives such as 2,2'thiodiacetic hydrazones have been

synthesized and characterized with the aid of physico chemical and spectral

methods. The complexes and ligands were screened for in vitro antimicrobial

activity and enhanced activity of the complexes over ligands was observed80

.

Six-methyl pyridine-isonicotnioyl-hydrazone, a good chelating agent was

successfully employed in determination of cobalt(II) and Ni(II) by HPLC81

. Iron

21

citrate complexes are known to study composition of plasma non-transferrin-

bound iron82

.Desferrioxamine and 1,2-dimethyl-3-hydroxy pyridine-4-one was

found to form chelates, iron from iron citrate complexes increases citrate ion

concentration favors chelatable iron and iron overloading disorders in patients

suffering from thalassemia was reported to be controlled83

. Co(II) complexes of

diethyl-nicotinamide coupled with P-Halogen-benzoate have also been reported

where Co(II) was linked to ligand through oxygen of acidic group and nitrogen of

pyridine ring84

. Cu(II), Co(II), Mn(II), Ni(II) complexes with amide derivatives of

2-amino-pyridine have been prepared and reported and square planar geometry for

Cu(II) complexes and octahedral geometry to other complexes was proposed on

the basis of elemental analysis, magnetic susceptibility and spectral studies85

.

Zn(II) complexes of macrocyclic ligand based on pyridine dicarbonyl derivatives

synthesized, Complexes were structurally characterized with aid of spectral reports

and screened for antimicrobial activity86

. Cobalt(II) chelates adopting hexa

coordinate geometry have been also synthesized from hydrazones of isonicotinic

acid hydrazide and characterized by spectral methods87

.

Square planar copper complexes and octahedral cobalt and manganese

complexes have also been reported to be isolated from 2-aminopyrimidine

derivatives88

.Simillarly studies on the structure of Vanadium carboxylates in solid

state was reported to be done on the basis thermal analysis89

.

22

Complexation of salicylate derivatives with Cu(II) was studied by UV-

visible, ESR and two dimensional simulation spectra and reported ‘mono and bis’

type complexes90

.Zinc complexes of the biomimetic N, N, O ligand,

alkylimidazole derivatives were studied both in solid and solution state. Different

coordination modes were found depending on both the stoichiometry and ligand

employed. A unique transformation of pyruvate into oxalate was found which was

resulted into isolation of new oxalate bridged zinc coordination polymer91

.

metal complexes of aromatic amino acids have proved to be simple

model systems for studying weak, non-covalent π interactions92

. Complexes of

Zn(II), Cd(II) and Co(II) with N-benzyloxycarbonyl glycine were synthesized for

first time and characterized by X-ray crystallography, Cd(II) complex was found

to be polymeric in nature93

.Hexacynoferrate(II) glycine complex of copper was

synthesized and reported that carboxylate groups of zwietterionic glycine are

coordinated with only copper cation94

. Transition metal complexes of azomethine

derivatives of alanine and histidine have been prepared and characterized. These

complexes were found to be non electrolytic nature and possess tetrahedral

geometry. The ligand was coordinated through O, N, O donor atoms to the

metals95.

Copper complexes of o-vanilin-taurine Schiff’s base and 1-10-

phenanthroline have been synthesized and thermo decomposition kinetic studies

were followed by Coats-Redfern integral method and Achar differential method.

Structure was confirmed on the basis of single crystal study96

.

23

Mannich base complexes of Co(II) and Ni(II) with 2-thioenyl glyoxal

amino-nicotinamide were synthesized and characterized. Magnetic and electronic

spectral data indicated octahedral environment around the metal97

. Mannich base

Co(II) complexes of hydroxyl benzyldine-2-amino thiazole were also isolated,

spectral studies indicated that ligands exhibiting bidentale O,N donor and

tridentate O,N,N donor systems revealed octahedral geometry around the metal

ion98

.

Ni(II) complexes of S3N2H2 adducts have been isolated and characterized on

the basis of IR, UV, 1HNMR and mass spectra. Ligand was coordinated to metal

through N and S atom to form three member rings99

.Copper and nickel complexes

of substituted pyrazole and isoxazole derivatives are also reported to

synthesised100

. Toxicological aspects of newly synthesized cobalt

tetrazamacrocycles have also evaluated recently101

. Pyridyl derivatives of

dimethoxyquinoxaline were also employed in synthesis of cobalt(II) complexes102

.

4[N,X-dimethylamino-benzaldehyde and o-aminophenol with transition metal

complexes formed were of 1:1 ratio103

. Copper and nickel mono and binuclear

complexes of aromatic hydrazones have been synthesized and reported104

.α-

Mercapto-2-aminophenyl-acetohydroxaminic acid transition metal complexes

have been prepared and Co(II) complexes reported to possess distorted octahedral

structure while Cu(II), Zn(II), Cd(II) found to be distorted tetrahedral in shape105

.

24

Semi conducting and biologically active transition metal complexes have been

isolated from 2-(2-amino1,3-thiazole-4yl)-4-chlorophenol and were characterized

by spectral methods and thermo gravimetrically and solid state conductivity has

been also measured106

. Copper(II)5-fluorosalicylic acid chelate exists in dimeric

form Cis-trans isomers of the complex were also characterized and on the basis of

ESR spectra, rhombic distortion of coordination polyhedral for species was

reported107

. Molecular weaving with octahedral structure around metal ions

resulting into tiles like polymers from pyrazine amide ligand was also studied108

.

Complexes of dithoaxamides with dihalogens are proved to be powerful reagents

in dissolution of noble metals. These complexes are supposed to provide

innovations in the recovery of noble metals109

.

Copper based complexes of quinoxaline derivatives are found to exhibit

hypoxic selective cytotoxicity towards V79 cells and super oxide dismustase

activity of the complexes was related to physicochemical properties of the

compound110

.

Transition metal complexes of β-diketone derivatives obtained from

cinnamaldehyde and acetyl acetone and its copper complex was synthesized and

characterized111

.Iron (III) complexes with β-diketone were isolated, complexes

were characterized and structure was elucidated on the basis of spectra. Redox

behavior was studied by cyclic voltametry, ESR and electronic spectral results

indicated presence of six coordinated Cu(II) ion112

. metal complexes with 2-(2-

25

carboxy-phenylazo)-1, 3-diaketones have been also synthesized. Ligand was

coordinated to the metal ion through one of the carbonyl groups of diketone

moiety, carboxylate oxygen and hydrazeno nitrogen. An EPR spectrum reveals

covalent character of Cu(II) complex. All the complexes were reported to be

potent bacteriacides113

.

Cobalt(II) and copper(II) complexes of disubstituted 3-aminopyazole

derivatives have been synthesized and an unusual coordination mode due to sterric

hindrance was revealed. Pyrozole moieties coordinated through oxygen atom of

acetyl group instead of nitrogen114

. Nickel(II) complex derived from pthalimido

ethylene diamine have been synthesized and characterized on the basis of X-ray

diffraction showed distorted octahedral geometry with trans-phthalimido ligands

and ethylene diamine moieties in equatorialposition115

β-halo-vinyl cobalt

porphyrin complexes revealed unusual reactivity. Trans-2-halo-substitution was

resulted in decreased vinyl c-c bond length116

.

Polymeric and non electrolytic complexes coordinated through SN-NS

donor system have been reported to be synthesized from Triazole derivatives with

transition metals and octahedral geometry to Co(II) and Ni(II) complexes while

pseudo tetrahedral geometry to Cu(II) complex is proposed117

. Zinc complexes of

manoazodyes have also been synthesized and tested for antimicrobial activity,

wash fastness, fastness to dry-cleaning and light fastness and are found to be

proved of good degree118

. metal complexes with O, N and S donor atoms such as

26

3-substituted–4-amino-5-mercapto 1,2,4-triazole have been synthesized and

reported. On the basis of elemental analysis and spectral studies, suggested to be

six coordinated geometry to the complexes119

.

Synthesis, characterization and biocidal studies of Co(II), Ni(II), and

Cu(II) complexes with chloro substituted formyl quinolin hydrogen has been

carried out and reported to have octahedral geometry and electrolytic in nature120

Polynuclear transition metal complexes with thiocarbohydrazide and

dithiocarbamate have been prepared and on the basis micro-analytical and spectral

methods square planar geometry was proposed to copper complex121

Copper(I)

complexes have been reported to be synthesized from p-isopropyl benzaldehyde

ligand and electrochemical behavior has been investigated by cyclic voltametry.

Structure of the complex was determined by single crystal x-ray diffraction

method122

.In the same way propanedithioic acid derivatives were also used to

prepare such complexes, Hammett correlations were studied and were found to

exhibit tautomeric equilibrium in solution123

. Structural and electronic differences

of Cu(I) complexes with tris(pyrazolyl) methane and hydrotris(pyrazolyl) borate

ligands were investigated. Difference in reactivity of complexes towards oxygen

was also noticed124

. Novel benzimidazole derived metal complexes of Fe(II),

Co(II), Ni(II) & Cu(II) have been synthesized and interaction Co(II) complex with

CT-DNA was studied. Mode of binding was studied by hydrodynamic

measurements125

. Marcocylic complexes of Ni(II) and Co(II) with

27

oxalodihydrazide have been prepared in crystalline state and characterized

spectroscopically126

. Copper(II) complexes based on thiophene derivatives

containing counter anions were also synthesized and structural elucidation was

made on basis of spectral results and aspects of anion coordination chemistry were

highlighted127

. Fe(III) and Mn(II) complexes of tridentate ligand 1,5 bis

(benzimidazolyl-2-yl)-3-thiapentane have been synthesized and characterized.

Massbauer data indicated high spin Fe(III) complex while slightly large

quadrupole splitting parameter indicated rhombically distorted centre. A strong

EPR signal centered at g >2 for Mn(II) complex proves non cubic crystalline weak

electric fields128

.

Metal lactates of some divalent transition metal ions were prepared and

characterized and reported to have attractive applications in biomedical and

pharmaceutical sciences129

. Cu(II) complexes with chelating amide ligands has

been studied and binding modes of amide ligand with metal and their structures

have been evaluated spectroscopically130

. Cu(II) complexes of monobasic

tridentate ligands containing S,O,O donor atom and S,O,O,N tetra dentate donor

ligands was studied, and reported to be non electrolytic nature having distorted

octahedral geometry with axial symmetry131

.

Iron(II) complexes having sixteen members was prepared from ligand acid

hydrazides and reported to undergo one step reduction accompanied by electron

transfer. E1/2 were found to be in the range of 1.34 to 1.5132

Macrocyclic

28

complexes from malano-dihydrazide with Ni(II) and Co(II) have been obtained,

were found to be of sixteen member macro cyclic ,crystalline state and in the form

of inner complex salt133

. Co(II) complexes of N-N-diethylnicotinamide and p-

Halobenzoate revealed monodentate nature of the ligand. Cobalt was bonded to

ligand through oxygen of carboxylate group and nitrogen of pyridine ring134

.

Polychelates of transition metals with ligand derived from 4-4′-bis

[salicylaldehyde-5] azo-biphenyl and 1,2-diamino propane has been isolated and

characterized by analytical and spectral methods. The ligand seems to coordinate

through phenolic oxygen and azomethine nitrogen atoms135

. N-hydroxylamine was

employed as analytical reagent in gravimetric estimation of copper(II). The ligand

formed complex and precipitated quantitatively and selectively in the PH range of

3.0 to 4-5. This method was employed for determination of copper in micro

quantities from alloys, minerals and biological samples136

.

Copper(II) complexes of dicoumarol derivatives have been derived and

characterized. Copper was coordinated to ligand and a system with six coordinated

dicumurol Cu(II) was investigated. Complexes showed effective DNA binding137

.

Molecular complexes of Co(II) and Ni(II) with 1-phenolbutane-1,3-

dionedihydrazone were reported. On the basis of magnetic moment and electronic

spectra distorted octahedral geometry has been suggested138

Transition metal

complexes of amino pthalocyanine derivatives have been prepared and

characterized. Magnetic moments of the complexes were found to vary with field

29

strength indicating inter molecular cooperative effects139

.Mn(II), Fe(III) and

Co(III) complexes with a Bis-hydrazones were isolated and on the basis of molar

conductance and spectral studies, electrolytic nature of the complexes having

octahedral geometry was reported140

.

Fe(III) and Cr(III) complexes of Loranzepam (1,4-benzodiazepine) have

been preparedin 1:1 ratio and spectral characterization, thermal decomposition and

antimicrobial studies have been conducted, bidentate coordination nature of the

ligand was concluded from spectral results141

. Transition metal complexes

from acetoacetanilide and anthranilic acid have been isolated and characterized on

the basis of analytical, magnetic and EPR studies. Nature of spin, number of

unpaired electrons, exchange interaction and coordination geometry have been

deduced from EPR studies142

.Hexa coordinated complexes of Co(II) and Ni(II)

with N-isonicotinamido salicylaldiamine and proposed hexa coordination around

the metal ion on the basis of spectral investigations143

. Transition metal complexes

of 2-thiopicoline amilide also prepared and characterized by physico-chemical and

spectral methods. Square planar structure to Cu(II) and octahedral structure to

Zn(II) and Cd(II) has been suggested144

. metal complexes derived from N-

substituted 2-aminopyridines have been synthesized and reported. From spectral

studies square planar geometry was proposed to Cu(II) complexes and octahedral

geometry for Mn(II), Co(II) and Ni(II) complexes145

. Chloro-substituted 3-formyl

quinoline hydrogen complexes of Co(II), Ni(II) and Cu(II) have been synthesized

30

and spectral as well as biocidal studies were carried out. Tridentate chelating agent

was bonded to metal through amine, imine nitrogen and chlorine atoms.

Octahedral geometry was proposed to these complexes146

.

Studies on DNA interaction and biocidal activities of Cu(II) complexes with

5-formyluracil substituted thiosemicarbazones were done. Copper atom was found

to be surrounded by S, N, O donor atoms of the ligands and two chloride ions

indicating penta coordination147

. New monochloro-2-substituted-benzimidazolato

cobalt(II) complexes have been synthesized and reported by Dubey and group.

Structural elucidations were done following FAB mass and magnetic studies148

.

Metal chelates of 5-[-(3-chloro phenyl), Piperazinyl-methelene]-8hydroxyquindine

were synthesized, characterized by elemental analysis, electronic and infra red

spectra. Metalocyclic complexes indicated metal ligand ratio of 1:2 for all divalent

metal ions and exhibit strong antifungal activity149

.

Mn(II) complexes of 2,5-dihydroxy-3-undecyl-1,4-benzoquinone derivatives

were of various pharmacological profile. Complexes were screened for

antibacterial, antifungal and antiheminthic activities and reported to show

enhanced activity over ligand150

. Eighteen to twenty two membered macrocyclic

manganese complexes of tetraazamacrocycles have been reported recently. On the

basis of spectral studies, an octahedral geometry for these complexes was

proposed as the binding sites were nitrogen of the macrocycles151

. Metal chelates

of hydrazo-pyrazolone derivatives synthesized by Alaudeen and co-workers were

31

found to be monomeric, distorted octahedral or tetrahedral geometry. These

complexes were of non electrolytic and diamagnetic in nature. Such complexes are

expected behave strong antioxidants, polymerization inhibitors as well as

fungicidal and pesticidal152

. Coordination complexes of N-phenyl–N′(2-

pyrimidyl)thiourea with divalent transition metal ions have been isolated and

reported, complexes were characterized by physico-chemical and spectral data

biological activity of the complexes was compared by Dunnett method153

.

Transition metal complexes of polydentate ligand 1,5-diamine-2,4-

dimethyl-1, 5-diaza,1,4-pentadiene have been synthesized in neutral medium.

Ligand was coordinated to metal ion through azomethine nitrogen. On the basis of

spectral data and thermal analysis octahedral geometry was proposed to the

complexes154

.

Complexes of Mn(II), Co(II), Ni(II) and Cu(II) have been synthesized with

arylhydrazone ligand. Complexes were characterized by elemental analysis, IR,

UV-visible, thermal, magnetic moment measurements and ESR spectra. ESR

spectra of the Cu complex revealed non-deformed octahedral geometry and no

magnetic dilution were achieved. Ligand was reported to coordinate through

nitrogen of amide and oxygen of azomethine group155

.

Iron(III) benzoin complexes in different ratios have been prepared and

characterized. IR spectra of complex indicate bonding through carbonyl and

32

hydroxyl groups in benzoin. Non-electrolytic complexes were expected to assume

octahedral geometry156

i(II) complexes of 1,3–bis(2-pyridylimino)isoindole was

synthesized, electrochemical properties were studied by cyclic voltametry. The

complex exhibited quasi-reversible and an irreversible ligand based reduction

processes157

Complexes of diaryethelene with metal hexafluroacetylacetonates

were prepared and their photo induced coordination structural changes were

studied. X-ray crystallographic analysis showed the formation of coordination

polymer. The complexes underwent reversible photochromic reactions by alternate

irradiation with UV and visible light in solution as well as in single crystalline

phase. Irradiation of UV and visible light, ESR spectra of the copper complexes

were reversibly changed158.

Mn(II) complex with 2,9-Bis-(n-2',5'-diazaheptanyl)1,10-phenanthroline is

synthesized and structurally determined by X-ray diffraction methods. Complex

having monoclinic system consists of one cation [Mn2]

2+ and [MnCl4]

2-. Mn(II)

ion is found to be coordinated to six nitrogen atoms of the ligand. Hydrogen

bonding between chlorine ions of [MnCl4]2-

and adjacent hydrogen atoms of imine

group was also reflected159

Macrocyclic Mn(II) complexes of ligands derived from

diacetyl pyridine and dicarboxylic acid hydrazone derivatives have been

synthesized. Complexes were characterized on the basis of physico-chemical and

spectroscopic method and octahedral geometry was proposed. Complexes showed

many fold activity in comparison with ligand molecules160

.

33

Genomic DNA binding studies of Co(II) and Ni(II) hydroxyl benzoate and

p-hydroxy benzoate complex were carried out and covalent intercalation binding

of metal complex with DNA was reported161-162

. Metal organic 1D supramolecular

complex of Cu(II) with 1,10-phenanthroline and biphthalate has been synthesized

and crystal structure was determined by single crystal. X-ray diffraction. Complex

belonged to orthorhombic crystal structure indicated that Cu(II) ion is five

coordinated in a square pyramidal geometry163

. Complexes of transition metals

with diphenyl pipperdin derivatives as ligand have been isolated and characterized

using spectral, magnetic, electrochemical, thermal and elemental analysis. X-ray

powder diffraction studies revealed that nickel complex crystallizes in tetragonal

lattice where as iron complex crystallizes in monoclinic form164

.

metal complexes of isonicotinoyl hydrazone-1-methyl-2-aldehyde pryrol have

also been reported, ligand was coordinated to metal ions by oxygen of amide and

nitrogen of azomethine groups. On the basis ESR, IR and electronic spectra

octahedral geometry to Cu(II), Co(II); tetrahedral geometry to Mn(II), Zn(II)

Cd(II) and square planar geometry to Ni(II) complex was proposed165

.

Fe(III),Cu(II),Zn(II) and Cd(II) complexes of N-isonicotinoyl

hydroxythiobenzenehydrazine were isolated and characterized by spectroscopic

methods.EPR spectra yield ‘g’ value characteristic of square pyramidal, octahedral

and square planar complexes where as massbauer spectra of the complexes at

room temperature and at 78 K suggested the presence of high spin Fe(III ) 166

.

34

Co(II), Ni(II) and Cu(II) complexes of N,N-di-n-propyl-N1-(2-chlorobenzoyl)

thiourea were synthesized and thermal behavior was studied by DTA and TGA

methods. Decomposition products were identified by GCMS system. Pyrolytic end

products were identified by X-ray powder diffraction method167

.

In Zn(II) complex of 8-hydroxyquuinoline-5-sulphonic acid ligand was

behaved as a neutral bidentate ligand coordinating through N and O atoms

diamagnetic complex was proposed to have tetrahedral geometry168

. Copper(II)

complexes of ketoanils have been synthesized and characterized by Poonam singh

and group. Ligand was coordinated to metal through azomethine and ketonic

group. On the basis of elemental analysis and spectral methods tetrahedral

structure was proposed to the copper complex169

. metal complexes of diphenyl-

piperdine-4-oneoxime derivatives have been synthesized and characterized by

electro analytical and spectral methods. X-ray powder diffraction studies revealed

tetragonal lattice system for nickel complex while iron complex crystallizes in

monoclinic form170

.

Cyclodichloro-phosphazene was used as a ligand to prepare complex with

CuCl2. It was concluded from IR, Uv-Vis and EPR studies that the complex is a

semiconductor polymer having composition [(P3N3Cl5)] + [(CuCl3)

-]

171. Similarly

copper complexes of cyclotriphosphazine have been also reported complexes were

characterized by 1H NMR and XRD. Triclinic structure with formula [(P3N3H6)

Cu] has been proposed to the complex172

. A rare syn-anti acetate bridged copper

35

(II) complexes having different geometry around each copper centre were also

recently reported173

.

Uncoordinated sites of the unimetallic complexes may bind to other metals

and yield complexes containing two or more metal ions174

. Such complexes are of

interest in several areas like multimetallic enzymes, homogeneous and

heterogeneous catalysis175

. Synthesis of such complexes is of current focus

justified by their structural diversity176

and potential applications as functional

materials in magnetism, molecular adsorption and light conversion devices177

.

Such complexes may be of homometallic or heterometalic multinuclear type.

Homometallic trinuclear copper(II) complexes bridged by phenoxy and benzyloxy

groups having linear trinuclear array of Cu(II) ions in which central ion is in an

octahedral and terminal one are in square pyramid geometry and the complexes

displaying strong anti-ferromagnetic coupling between the metal ions have been

reported178

.

A trinuclear polymeric Cd(II) complex with N-benzyl oxycarbonyl glycine

is reported. Crystal structure was resolved by X-ray single crystal analysis and

cadmium ion reported to be in distorted pentagonal bipyramidal coordination. In

2D supramolecular structure, phenyl rings interact mutually by CH-π

interactions179

. Manganese complexes of 2-mercaptonicotinic acid are reported to

be of linear chain polymer. Since the ligand is multifunctional, exhibits different

structural form and co-ordination modes180

. Tetranuclear pyrophosphate bridged

36

copper(II) complex with 2,2–dipyridil amine was characterized by spectral and

variable temperature magnetic susceptibilities, extensive π-π stacking and

H-bonded water molecules found to join Cu4 units to make 3D network181

.

Di-nuclear complexes of Fe(III) with ciprofloxacin have been synthesized and

subjected to spectral investigation, biocidal study and SH-DNA binding study,

these complexes were found to assume a six coordinated dimeric distorted

octahedral geometry and show effective binding to SH-DNA182

. Transition metal

complexes of Schiff base derived by condensation of pyridine dicarboxaldehyde

and 8-amino quinoline have been reported to be mono, bi or trinuclear nature183

.

Binuclear metal complexes of Ni(II) and Cu(II) with 1-4-dihydro-9,10-

anthroquinone has been synthesized and studied, on the basis of magnetic moment

and spectral studies suggested octahedral polymeric structure was concluded184

.

Chromium(II) complexes of pyridine derivatives were also found to be bridged

type where two chromium atoms attached to ligand have formed metal-metal

bond, such complexes have played major role in the quadruple study185

. Cr2(L)4.

H2O type of complexes having Cr≡Cr bond has been prepared from 3-cyno-2(H)-

pyridone derivatives in which ligand acts as a 1-3 bridging. Complexes formed

were remarkably stable. Interestingly nitrogen of cyno group was not found to

involve in bonding186

. One dimensional Cu(II) polymeric complex having µ4

bridge connecting Cu atoms into chains has been synthesized from catena-poly [µ-

salicylidene-p-methyl phenoxyacetyl hydrozino ligand. The complex is reported to

be of tetragonal system and Co(II) adopted a distorted square planar geometry.

37

Electrochemical study of the complexes revealed that it can bind to DNA by

intercalative binding187

.

Hetero-bimetallic complexes of transition metals were synthesized from

polyfunctional bis (2-hydroxy-1-napthaldehyde) malonoyl-dichydrazone and

characterized by thermal and spectral methods in all complexes dithiohydrazone

coordinated to the metal centers by an anti-cis-configuration188

. Hetero-metallic

complexes of the type 3d-4f metal azido have been isolated from Gd(III) and

Ni(II) with isonicotinic acid by hydrothermal method. The complex was found to

possess three dimensional unprecedented structures. Magnetic properties of the

complex indicate its applicability as magnetic material189

Sulfonatothiacalix-[4]-

arene heterometallic CoIII

-LnIII

complexes are reported to exhibit redox switchable

metal to metal energy transfer190.

Novel Cu(I)–Ge(II) complexes of the type [Me2

Cu-Ge (NMeS)2 (CH)2] have been also synthesized and characterized by X-ray

crystallography. The complexes were found to be highly reactive with dioxygen

and exhibit chemistry depended upon bound germylene, such complexes operate

synergistically to activate O2 as they are implicated in some synthetically and

biologically useful catalytic reactions191

. Binuclear copper(II) complexes of

decadentate Schiff base derived from condensation of 3,5-di-tert-butyl-

salicyaldehyde with Branched EDTA have been synthesized and characterized by

13C NMR, Uv-Vis and IR spectra and confirmed by elemental analysis192

.

38

Cyanide and oxalate bridged heterometallic complexes of Cr-Mn based on

building blocks [Cr (L) (CN)] - where L= phen and bipyridine have been prepared.

X-ray crystallography revealed that cyno bridged unit has ladder like chains that

are further connected through oxalato bridges to yield two dimensional structures.

Magnetic studies have indicated antiferromagnetic interactions between

cynobridged CrIII

-MnII and oxobridged Mn

II-Mn

II ions

193.Cynobridged bimetallic

complexes of the type Fe-Mn of 2-2′-bipyridine and tris-(Pyrazolyl) hydroborate

have also reported. These compounds exhibit weak ferromagnetic interactions,

antiferromagnetic coupling or Meta magnetic like behavior194

. Trinculear CrIII

-

MnII complex with cyanide bridge from [Ni-Ni (Salicyl) ethelendiamine has also

been reported. Structure of the complex was characterized by X-ray diffraction

method. Magnetic coupling between Mn(II) and Cr(III) ions in the present

complex was found to be anti ferromagnetic on the basis of Hamiltonian195

. One

dimensional cyno-bridged CuII-Ni

II, Cu

II-Pd

II and Cu

II-Pt

II bimetallic assembles of

cis and trans cyclohexane-(1, 2)-diamine have been prepared and characterized on

the basis of electronic spectra. Temperature dependence magnetic measurement

indicated weak anti-ferromagnetic interactions. Because of semi coordination

coupled pseudo John-Teller elongation and electrostatic interaction, the axial Cu-

N coordination bond distances were considerably longer than that of equatorial

ones196

.Novel trinuclear copper complex bridged by phenoxy and benzyloxy

atoms was synthesized and characterized by X-ray diffraction studies. The crystal

structure of the complex revealed linear trinuclear array of Cu(II) ions in which

39

central copper ion was in an octahedral coordination and the terminal being

identical possess square pyramidal structure197

Hetero-bimetallic complexes of

Pd(II) and Co(II), Ni(II), Mn(II) with 4,5diphenyl-1,2,4-Triazole-3-Thione were

prepared in acetone. Complexes were characterized by elemental analysis,

magnetic susceptibility, IR, Uv-Vis 1HNMR and

31PNMR methods

198.

Hetero-binuclear azine bridged complexes of the type LnIII

-ZnII have also

reported to be prepared from 2-acetylpyridine salicylaldazine ligand199

Binuclear

and tetra nuclear metal complexes of Cu(II), Ni(II) and Co(II) with Schiff base

derived from 3-formylsalycilic acid and p-Phenylene diamine have been reported

to have Oxo-bridge. Binuclear metal complexes assumed planar/tetrahedral

geometry with lower magnetic moment values, while tetra nuclear complexes

show strong anti-ferromagnetic interaction due to presence of an Oxo

bridge200

Bimetallic µ-Oxoalkoxides containing M-O–M unit of Sn(IV) and Al(III)

have been synthesized from β-diketonate. Such bimetallic µ–oxoalkoxides are

reported to be among the best catalysts for polymerization of heterocyclic

monomers201.

40

1.5. References:

1. Kamalesh Bansal.; Coordination chemistry. Campus Books international

publisher New Delhi (2000)

2. Pathania.V.B.; Chemistry of transition elements, Campus books international

New Delhi.

3. Gurudeep Raj.; Advanced Inorganic chemistry, Goel publishing house Merut.

4. Manku.G.S.; Theoretical principals of inorganic chemistry, 22nd

reprint. Tata

Mc Grow hill publisher New Delhi.

5. Cotton,F.A., and Wilkinson, G.,; Basic Inorganic Chemistry Third edition,

John Wiley and sons publishers.

6. Lee.J.D.; Concise inorganic chemistry. Fourth edition ELBS. With Chapman

& Hall.

7. Emelius.H.J., and Sharpe,A.G.; Modern aspects of Inorganic chemistry,

fourth edition. Universal Book stall. New Delhi.

8. Shriver Atkins and Long ford. ; Inorganic chemistry, third edition. Oxford

University press.

9. James Huhey.; Inorganic Chemistry principles of structure and reactivity.

Fourth edition, Pearson edition.

10. Cotton, F.A and .Wilkinson, G.; Advanced Inorganic Chemistry, fifth edition.

Wiley interne science publication.

11. Douglas,B D. Mc Denial and .Alexaneder. J.; Concepts and models of

inorganic chemistry, Third edition, John Wiley and sons Singapore.

12. Hassan, H..S, .Jamil A.F., Seyedeh R.H., Hamid R.K. and Rainer P.;

Polyhedron 27 (2008) 249-254.

41

13. Ursula K. L, Justyn, O. and Ksenia M.W.; Molecular Biology and plant

Biotechnology. Poland 1, 90-151.

14. Zhang, H, Joy. J, Jeannette V.V., Hakim. K., Cline. N, Pavel .M, Paul T and

Kalyanraman B.; FEBS. Letters 473(2000) 58-62.

15. Skoog, D.A, West, D.M., Holler, F.J., and Crouch, S.R.; Fundamentals of

Analytical chemistry, Eighth edition. Thomson books, Thomson business

information India pvt ltd.

16. Day, R.A., and Underwood, A.L.; Quantitative analysis, sixth edition.

printice hall of India New Delhi.

17. Kalsi, P.S.; Spectroscopy of organic molecules. Sixth edition. New age

international (p) Ltd. Publishers New. Delhi.

18. Parikh.V.M.; Absorption spectroscopy of organic molecules, second printing.

Mehta publishing house Pune.

19. Chatwal, G.R and Anand, Sham; .Instrumental methods of chemical analysis,

seventh edition. Himalaya publishing house New Delhi.

20. Laxman Singh, Upma Singh and Deepak K Sharma.; Asian J.chem. Vol.

14(2), (2002) p. 484.

21. Anne, S., Riemann R.E.; Risk of administering Cephalosporin antibiotic to

patients with histories of penicillin allergy. An allergy

asthma.;Immunol.vol.74 (1995), p.165.

22. The choice of antibacterial drugs; Med. Lett. Drugs.Vol 38 (1996), p. 25.

23. Sharma S.K.; An investigation on transition metal complexes of

biologically active Schiff bases derived from 4-amino antipyrine and

isonicotinic acid hydrazide Ph.D. Thesis. Merut University.1993.

24. Raj, B.K., and Akilesh Baluni; Asian J. chem. vol.(1), 2002, p. 305.

42

25. Bahamaria, B.K., Bellure, R.A and Dellwala, C.V.; J.Exp.Biol.Vol.6 (1968),

p. 62.

26. Deshpande, D.S., Kulkarni, A.P., and Dev, D.V.; Heterocyclic.22 Vol.16

(1981) p. 707.

27. Raj, B.K., and Poonam Choudhary; Asian J. Chem. vol 14(1)2002, 312.

28. Eleni K. Efthimiadou, Maria E. Katsarou, Alenxandra Karaliota and George

Psomas.; J. Inorganic Biochem. 102(2008), p. 910.

29. Petar Dorkov. Ivayla. N; Pantcheva William S. Sheldrick, Heike-Mayer-

Figge, Rosiitza Petrova and Marriana Mitewa.; J. Inorg. Biochem. 102

(2008), p.26.

30. Farideh J., Bonnie O.L., Maryam I., and Emilina Damian.; Inorg. Chem; 45

(2006), p.66.

31. Leena Gandhi and B.S. Shekhon.; J. Ind. council chem. 24(2)2007,68-72.

32. Shelly Arreguin, Paul Nelson, Shelby Padway, Matthew Shirazi and

Cortlandt piperpont.; J. Inorg. Biochem. 103(2009),p. 87.

33. Urszula Kalinowaska-Lis, Justyn Ochocki and Ksenia Matlawska-

Wasowska.; plant biotechnology, university of Lodz, Banacha, Poland.

p.90

34. Angela Serpe, Flavia Artizzu, Maria Laura Mercuri, Luca Pilia and paola

Deplano. Dept of Chimica inorganica and analitica, University of Cagliari,

S.S.554, Bivio per sestu, I-09042.Monserrato (CA) Italy.

35. Murali Krishna,P., Husain Reddy, K.,; Pitchika G.Krishna & Philip, G.H.;

Indian J. Chem.. 46(A) (2007), p. 904.

36. Kamal M.Ibrahim, Sohar I Mostafa, Nagwa Nawar and Zeinab A. Yunis.;

Indian J. Chem. 43(A) (2004), p. 2294.

43

37. Haiyan Zhang, Ronald Thomas, David Oupicky and Funggu Peng. J.

Biological Inorg. Chem. SBIC-2007, p.0299.

38. Hussain Reddy, K., Surendrababu, M., Subhash Babu,P., and .Dayanand,S.;

Ind. J. Chem. 43(A) (2004), p. 1233.

39. Brajesh kumar, Sangal,S.K., and Arun kumar. ; Asian Jr. Chem.19 (1)

(2007), p. 647.

40. Latha,K.P,. Viady,V.P., and .Keshawayya, J.; J. Indian Council Chem. 24(2)

(2007), p. 25.

41. Majed M. Hania. ; Asian Jr. Chem.19 (3) (2007), p.1897.

42. Ivanov, A.V., Korneeva, E.V., Bukvetskii,B.V., Goryan,A.S., Antzutkin,

O.N, and Forsling,W.; Russian J. Coord. Chem., Vol. 34 (1) 2008, p.59.

43. Pampa Mukharjee, Michael G.B. Drew, Marta Estrader, Carman Diaz,

Asutosh Ghosh;. Inorganica Chimica Acta. 361 (2008), p.161.

44. Makode, J.T. and Aswar,A.S.; Ind. J. Chem. Vol.43 (A) (2004), p.1.

45. Sabarina Belaid, Anne Landreau, Safia Djebbar, Ouassini Benali-Baitich,

Gilles Bouet and Jean phillippe bouchara.; J. Inorg. Biochem. 102(2008), p.

63.

46. Mishra,A.P., Nehasharma and Monika Soni.; In 25th

annual conference of

Indian council of chemists. P. 18 (2006).

47. Ibrahim Demir and A.Ishan Pekacar. ; Asian J. Chem. 19(3) (2007), p.1919.

48. Ping Zhang, Mei Tang and Xiaoping Lu.; Asian J. Chem. 19(3) (2007),

p.2083.

49. Ibrahim Demir, Mustafa Akkaya, Mevlut Bayraket and A. Ishan Pekacar;

Asian Jr. of Chem. 19(5) (2007), p. 3954.

44

50. Mishra,A.P., Raj, K.K. and Tiwari, S.C.;. In 24th

annual conference of

Indian council of chemists. P. 11 (2005).

51. Vivekanand and .Bhandari, N. S.; Asian J. Chem. 19(6) p. 4225.

52. Hankare, P.P., Gavali, L.V., Bhuse, V.M., Delekar, S.D and Rokade; R.S.;

Ind. J. Chem. 43(A) (2004), p. 2578.

53. Mukerrem Kurtoglu and Esin Ispir.; Asian J. Chem. 19(2) (2007), p. 1239.

54. Et. Ajaily, M.M., and Morad, F.M.; Asian J. Chem. 19(6) 4379-4484.

55. Mehta, B.H., and More, P.S.; Asian J. Chem. 19(5) (2007) p. 3581.

56. Gupta, K.C., and Alekha Kumar Sutar. Polymer research bulletin. IIT

Roorkee. India.

57. Zoeb A.F. Sanjay M.N. and Raju M.P.; Asian J. Chem. 19(6) (2007) p. 4697.

58. Jojo Joseph and Mehta, B.H.; Asian J. Chem. 19(1) p.401.

59. El-Ajaily, M.M., and El-Saied, F.M.; Asian J. Chem 19(6) (2007) p. 4433.

60. Hassan A Tayim and Abdu S. Salambh. ; Asian J. Chem.19 (2) (2007),

p.1423.

61. Manjunathan, S., and .Krishnan, C.N.; Asian J. Chem.19 (2) (2007), p. 861

62. Kadir Devrim, A Ali Arslantas, Necati Kaya and Hacali Necefoglu.; Asian J.

Chem. 19(3) (2007) p. 2374.

63. Jain, Chetana, Dwivedi, Rashmi Nee Mishra, Vinod kumar and Rajesh

Dhakarey.; in 24th

annual conference of Indian council of chemists. P 27

(2005).

64. Selwin, R., Josephus and Shivsankaran Nair, M, In 25th

annual conference of

Indian council of chemists P. 5,(2006).

45

65. Hemalata Yadav, Rashimi Dwivedi nee Mishra, Vinod Kumar and Rajesh

Dhakarey.; in 24th

annual conference of Indian council of chemists P. 28

(2005).

66. Mukerrem Kurtoglu and Esin Ispir.; Asian J. Chem. 19(2) p. 1239.

67. Halli, M.B, Qureshi, Z.S., Vitthal Reddy, P., Jumanal, B.A., and Vijayalaxmi

B. Patil.; J. Ind. Council. chem.25 (1), (2008), p.1.

68. Mehta, B.H., and More, P.S.; Asian J. Chem.19 (6) (2007), p. 4719.

69. Amirreza Azadmeher, Mostafa M.Amini, Nasser Hadipour, Hamid Reza

Khavasi, Hoong-Kun-Fun and Chun-Jung-Chem.; Applied Organomettalic

chemistry .22(2008), p.19

70. Ramachandra Moorthy, T Paul Raj, A., Shivsankar, V., and Shameela

Rajam.; Asian J. Chem. 19(6) (2007), p.4415.

71. Hong-Ping Xiao, Bao-Lin-Liu, Xiao-Qiang Liang, Jing-lin-Zuo and Xiao-

Zing You. Inorg. Chem. Comm. 11(2008), p.39.

72. Kelkar,V.D., Kanase,V.G., Kadam , S.S.,and Takale, S.T.; Asian J. chem.

19(5) 2007,p. 3597.

73. Robert W.E., Roozina R., Adel Zarea, Chiara R., Richard C., Patrica J.

Evans, John B. Porter and Robert C. Hider.; J. Biol. Inorg. Chem. 297 (8)

(2007), p.1.

74. Paradeshi,S.K., Kumbhar,D.D., and Waghmare, W.A. In 25th

annual

conference of Indian council of chemists. P. 42 (2006).

75. Ramachandramoorthy,T., Paul Raj, A., Shivashankar, V., and Shameela

Rajam.; Asian J.Chem19 (6) p. 4415.

76. Jitendra Ambuwani and Sunita Singh. In 25th

annual conference of Indian

council of chemists P.31, (2006).

77. Mehta, B.H., and More, P.S.; Asian J. Chem. 19(6) (2007), p.4719.

46

78. Sha Raj Ali and Venkareshwarrao, K.T., in 25th

annual conference of Indian

council of chemists.(2006) p.28

79. Agarwal,R.K., Lakshman singh and Surya Prakash. In 25th

annual conference

of Indian council of chemists P.23 (2006).

80. Amita Agrawal, Shanu Das and Rajesh Dhakarey. In 25th

annual conference

of Indian council of chemists P.27, (2006).

81. Li-Rong Yang, Cai Feng Bi,Yu-Hau Fan,Si-Quan Lu. Feng Guo and Xiao-

Kang Ai.;Asian J. Chem.19 (1) (2007), p. 195.

82. Rajeev Singh Yadav. in 25th

annual conference of Indian council of

chemists.(2006) p.30

83. Manoj Kumar and S.P.S. Jadon.; Asian J. Chem.19 (5)(2007), p. 4115.

84. Gayatri Kumar, Gautam Jaiewar and Rajesh Dhakarey. In 25th

annual

conference of Indian council of chemists P 43. (2006).

85. Senthil kumar,R., Arunachalam,S., .Periasamy, V.S., Preethy, C.P.,

.Riyasdeen, A., and Akbarsha, M.A .;J . Inorg.Biochemistry.103 (2009)

p.117.

86. Ravinder,V., Narasaiah,V., Bhugangarao, A., and Murlidhar Reddy, P.; J.

Indian Council Chem. 23(2) (2006), p. 4.

87. Pieter C.A. Bruijnincx,Martin Lutz, Johan P.den Breejen,Anthony L.Spek,

Gerad Van Koten and Robertus J.M.Kelin Gebbink.; J. Biol.Inorg.chem. 10

(2007), p. 285.

88. Maihub, A.A., .Et-Ajaily, M.M., and .Hudere, S.S.; Asian J. Chem.19 (1)

(2007), p.1.

89. DJenana U.M.; Dragana M.M., Zoran M.M., Goran A.B., Zeljko J.V., Maja

D.V., Milanaka D.R. Branishow J.N., Ivan O.J. and Katarina K.A;

Inorganica. Chimica Acta. 361 (2008).p. 86.

47

90. Mandal, R.S., and Lalita Mishra.; Asian J. Chem.19 (1) (2007),p 95.

91. Shrivastava, K.P., and Nirmal kumar Ojha.; Asian J.Chem.19 (1) (2007), p.

385.

92. Vukadin M. Zoran D.T., Attila K., Milan D.J. Lijiljana S.J. and Katalin M.S.;

J. Organometallic Chem. 693 (2008), p . 77.

93. Yu-Min Liu and He Liu.; Asian J. Chem.19 (2) (2007), 1187-1190

94. Amita Agarwal, Shanu Das and Rajesh Dhakarey.; in 25th

annual conference

of Indian council of chemists. P. 27 (2006).

95. Mojtaba Bagherzadeh and Mojtaba Amini.; Inorg. Chem. Comm. 12(2009) p.

21.

96. Solanki, P.R., and Narwade, M.R.; J. Indian Council Chem. 24(2) 2007,

p.43.

97. Rai, H.C., and Ashwini kumar. In 24th

annual conference of Indian council of

chemists. P. 31 (2005).

98. Gour,S., .Purohit, R., and Ranka, M.,; J. Indian Council Chem. 24(2) 2007,

p.51.

99. David L. Cockreil, James M. Mc Clain, Kaushal C. Patel. Robert Ullom,

Travis R. Hassley, Stephan J-Archibald and Trimothy J. Hubin.; Inorg.

Chem. Comm.; 11 (2008), p. 1.

100. Aswar,A.S Bansod, R.D., and Mahale, R.G.; J. Indian Council Chem. 23(2)

(2006), p.10.

101. Veeraraj, V., .Sami, P. and Raman, N.; Proce. Indian Acad Sci. (Chem. Soc.)

112 (2000), p. 515-521.

102. Carolina Urquiola, Dinorah, G. Mauricio C., Maria Laura L., Hugo

Cerecetto, Mercedes. G. Adela Lopezede C., Anttonio, M. Antonio J. Costa-

Filho and Maria h. Torre; J. Inorg. Bichemistry.102 (2008), p.119.

48

103. Mathews Cheriyan and K.Mohanan; Asian J. Chem. 19(4) (2007), p.2831.

104. Terezia Szabo-Plankla ,Bela Gyurcsik, Nora Veronika Nagy, Rockenbaur,

Rastislav Sipos, Jozef Sima and Milan Melnik.; J. Inorg.Biochemistry.102

(2008), p.101.

105. Maxmillan N.K., Matti H., Alexander M., Vadim Y.K., and Armando J.L.

Pomberio.; Inorg. Chem Comm. 11(2008), p. 117.

106. Maskar,P.T., Patil, R.M., and Saikh, M.M.; Asian J. Chem. 19(6) p.4563.

107. Teli, M.D., .Sekar, N., Jain, A., and Prabhu, K.H.; Asian J. Chem. 19(6)

p.4615.

108. Sonawane, S.M., Gill,C.H., Bhosale, A.M., and Karal, B.K.,. In 25th

annual

conference of Indian council of chemists P.21, (2006).

109. Carolina Urquiola, Dinorah, G. Mauricio C., Maria Laura L., Hugo

Cerecetto, Mercedes. G. Adela Lopezede C., Anttonio, M. Antonio J. Costa-

Filho and Maria h. Torre; J. of Inorg. Biochemistry. 102 (2008), p.119.

110. Ivan. G.O., Jose. G. Lopezcortes, M.Carmen Ortego Alfaro, Ruben Alfredo

Toscano, Guillermo Peniers-Carillo and Cecillio Alvarez-Toledano.; Inorg

Chem. 43 (2004), p.8572.

111. Kiyoshi Fujisawa, Tetsuya Ono, Yoko Ishikawa, Nagina Amir,Yoshitaro

Miyashita,Ken-ichi okamoto and Nicolai Lehnert. Inog

Chem.45.(2006),p.1698.

112. Lata Nohria and Pavan Mathur.; Ind. J. of Chem. 43(A) (2004), p. 548.

113. Joseph. M.F., Noah. D.R. and Kristopher McNeill.; Inorg. Chem .45

(2006), p. 2228.

114. Vidyevati Reddy, Nirdosh Patil and B.R. Patil.; J. Indian Council Chem.

23(2) (2006), p. 1.

49

115. Rai, H.C., and Ashwini Kumar.; in 24th

annual conference of Indian council

of chemists P. 31 (2005).

116. Elif.F. Ozturkkan, Drusun Ali kose,Hackli Necfoglu and Ibrahim Uzun. ;

Asian J. Chem. 19(6) (2007), p. 4880.

117. Farukh Arimand and Mubashira Aziz. In 25th

annual conference of Indian

council of chemists P.9 (2006).

118. Siddiqi,K.S., Sadaf Khan and Shahab A.A.Nami. In 25th

annual conference

of Indian council of chemists P.7, (2006).

119. Mohanan, K., and Sheeja Mathews.; In 25th

annual conference of Indian

council of Chemists. P. 21 (2006).

120. Murali Krishna P and Hussain Reddy. In 25th

annual conference of Indian

council of chemists P.7, (2006).

121. Pratibha Jadhav,P.S.Khanadgale, V.D.Kelkar, Mrudula Wadekar and

Asmita Prabhune. In 25th

annual conference of Indian council of chemists

P.24, (2006).

122. Sushama Sinha Kusheshwar Yadav and Deonath Rai. In 25th

annual

conference of Indian council of chemists P32. (2006).

123. Devhade, J.B., and Aswar, A.S., In 25th

annual conference of Indian

council of chemists P.33, (2006).

124. Vijay Kumar and Ramesh Kumar. In 25th

annual conference of Indian

council of chemists.(2006) p.37.

125. Ivan Garcio-Orozco, Jose G.Lopez-Cortes, M.Carmen Ortega-Alfaro,

Ruben Alferdo Toscano, Gullimero Pemieres-Carillo and Cecillo Alvarez-

Toledano.; Inog.Chem.43.(2004)

126. Narsaih,V , Shankar,K Balaswamay, G., and Ravinder, V.; In 25th

annual

conference of Indian council of chemists. P.26 (2006).

50

127. Shrivastawa, K.P., and Nirmal Kumar Ojha. In 25th

annual conference of

Indian council of chemists P.27 (2006).

128. Sushilchandra Tiwari. In 25th

annual conference of Indian council of

chemists P.34, (2006).

129. Vijay Kumar and Ramesh Kumar. In 25th

annual conference of Indian

council of chemists P.37, (2006).

130. Patel, I.J., and Vohra, I.M., Asian Jr. of Chem 19(5) (2007), p. 3393.

131. Jha , R.R.,and Mukharjee, P.; Asian J. Chem. 19(1) (2007) p.641.

132. Sushma, P.G Dorothy, M and Alaaudin. ; Asian J. Chem. 19(5) (2007)

p.3403

133. Et-Ajaily, M. M., Maihub, A. A., .Abuzwida,M.A, Abou-Krisha,

Amar,A.A and Ashih, E.A.; Asian J. Chem. 19(1) (2007), p. 781.

134. Promod B.Pansuriya, Mapara, M.B., and .Patel, M.N., In 25th

annual

conference of Indian council of chemists P.35, (2006).

135. Sushil Chandra Tiwari. In 25th

annual conference of Indian council of

chemists P.34, (2006).

136. Bayazeed H. Abdullah.; Asian J. Chem. 19(5) (2007), p. 3903.

137. Alaudeen M Sushma P.G & Dorothy M; Asian J. Chem. 19(5) (2007)

p.3407.

138. Jitendra Ambiwani and Sunita Singh. In 25th

annual conference of Indian

council of chemists P.31, (2006).

139. Kasim Senar.M.; Asian J. Chem.19 (3) (2007), p. 1870.

140. Pramod B. Pansuriya, M.B. Mapara and M.N. patel. In 25th

annual

conference of Indian council of chemists P.37, (2006).

51

141. Feng-Hau Li, Tian-Fu Liu, Hau-Kuan Lin, Xue-Mei Li and Shu-Sheng

Zhang. ; Asian J. Chem. 19(3) (2007) p.1988.

142. .Kadir Devrim, AAli Arslantas, Necati kaya and Hacali Necefoglu.; Asian

J. Chem.19 (3) (2007), p. 2374.

143. Kadir Devrim, AAli Arslantas, Necati kaya and Hacali Necefoglu.; Asian J.

Chem.19 (7) (2007), p.5417.

144. Mitu.L. andAngela Kriza. ; Asian J. chem.19 (1), 2007, p.658.

145. Murukan.B.In25th

annual conference of Indian council of chemists P.8,

(2006).

146. Jian-Hong Bi,Fu Hou Yao,Zi-Xang Hung, Hung-Ling Wang and and Nai-

Lang Hu. ; Asian. J. Chem. 19(7) (2007), p.5360.

147. Murukan B. & .Mohana, K.,In 24th

annual conference of Indian council of

chemists P. 9 (2005).

148. Gun Binzet, Haken Arslan and Nevzat Kulcu.; Asian J. Chem. 19(7) 2007

.p. 5711.

149. Neeraj Sharma, Pinky Gautam, K.Chaturvedi and G.K.Chturvedi. in 24th

annual conference of Indian council of chemists

150. Lakshman singh. In 24th

annual conference of Indian council of chemists P.

18 (2005).

151. Yogendra Jha. In 24th

annual conference of Indian council of chemists

P21.(2005).

152. Ravinder , V.Narasaiah and A. Bhujangrao. In 24th

annual conference of

Indian council of chemists P. 24, (2005).

153. Rai.B.K.,In 24th

annual conference of Indian council of chemists P.25,

(2005).

52

154. .Dubay, R.K., Mishra,C.M,Dubay S.S., In 24th

annual conference of Indian

council of chemists P. 32, (2005).

155. Jha, R.R., and .Mukharji, P.; Asian J. Chem.19 (1) (2007), p.641.

156. Ashu Chaudhary and R.V.singh .;Ind. J. Chem. 43(A) 2004, p.2529.

157. El-Ajaily,M.M., Maihub, A.A., Abuzwida,M.A., .Abou-Krisha,M.M.,

Amar,A.A., and .Ashih, E.A.; Asian J. Chem.19 (1) (2007), p.781.

158. Rai,B.K. ;J. Ind. council chem.23 (2), 2006.p.13.

159. Latha Nohria and Pavan Mathur.; Ind. J. chem. 43(A) 2004, p.548.

160. Shobhana.D; Asian J. chem.19 (4), 2007, p. 2667.

161. Hassan Hadadzadeh, S.Jamil A. Fatemi, Seyedch Raziyeh Hasseinian,

Hamid Reza Khavasi and Rainer Pottgen.; Polyhedron 27 (2008).p.249.

162. Sharma.H.K.; Asian J. chem. 19 (7), 2007, p.3247 .

163. Jian-Hong Bi, Ling-Tao Kong and Xian Hung.; J. Chem. 19(7) (2007),

p.5229.

164. Kadir Devrim, A., Ali Arslantas, Necati Kaya and Hacali Necefoglu.; Asian

J. Chem. 19(7) (2007),p. 5417.

165. Kenji Matsuda, Koshuke Takayama and Masahiro, Ire.; Inorg. chem.43

(2004) p.482.

166. Hossein Haghgooie, Liela tabrizi and Sirous Nouri.; Asian J. chem.19 (6).

2007, p. 4463.

167. Mitu, L., Angela Kriza and Mariana Dianu.; Asian J. Chem. 19(7)2007. p.

5666.

168. Manimekalai, A., and Mahendrian, R.; Ind. J. Chem. 43(A) 2004.p. 88.

169. N.K.Singh,N.K.,and Kushawaha,S.K.; Ind. J. chem. 44 (A) (2004). p.61.

53

170. Hamidkhan Mohammadi.; Asian J. Chem.19 (1) (2007), p. 459.

171. Elif F. Ozturkkan, Drusun Ali Kose, Hacali Necefoglu and Ibrahim Uzun.;

Asian J. Chem. 19(6) (2007), p.4880.

172. Jitendra Ambuwani and Sunita singh. In 25th

annual conference of Indian

council of chemists p.31. (2006).

173. .Kadir Devrim, A., Ali Arslantas, Necati Kaya and Hacali Necefoglu.;

Asian J. Chem. 19(3) (2007), p.2369.

174. Vijay Kumar and Ramesh Kumar. In 25th

annual conference of Indian

council of chemists P. (2006).

175. Manimekalai, A., and Mahendrian, R.; Ind. J chem. 43(A) 2004.p.88.

176. Poonam Singh, Seema Attri and R.K. Upadhay.; J. Indian Council Chem.

23(2) (2006), p. 20.

177. Han-ping Zhang, Hong Zhou, Zhi-Quan Pan, Xiang-Gao Meng and You

Song.; Trans. Metal Chem.33 (2008), p.55.

178. Baccha singh, Asutosh K,shrivastava and Praveen.; Indian J. chem.vol.36

A (1997), p.72.

179. Lal, R.A., Chakraborty, J., .Kumar,A., .Bhaumik,S., Nath, R.K., and

Ghosh.D.; Ind. J. chem. 43 A (2004).p. 516.

180. Jian-Hong Bi, Ling Tao Kong andZi-Xian Hung.; Asian J. chem.19 (7).

2007, p.5229.

181. John. T.Y., Victor G.Y. Jr and William B.T.; Inorg. Chem. 45(2006),

p.4191.

182. Jing yuan Xu, Jin-Lei-Tian, Quing-Wei-Zang, Zing-Zhao, Shi-Ping-Yan

and Dai-Zheng Liao. ; Inorg. Chem. Comm,. 11 (2008),p. 69.

54

183. Pramod Pansuria and .Patel, M.N,, In 25th

annual conference of Indian

council of chemists. (2006) p.16.

184. Lal, R.A., Chakraborty, J., .Kumar,A., .Bhaumik,S., Nath, R.K., and

Ghosh.D.; Ind. J chem. 43 A (2004). P.516.

185. Birendra Kumar and Brameshwar. In 25th

annual conference of Indian

council of chemists P. 20,(2006).

186. Pramod Pansuria, M.B. Mapara and M.N.Patel. In 25th

annual conference

of Indian council of chemists.(2006) p.35.

187. Fu-Chen Liu, Young-Fie Zeng, Jiao Jiao, Jian-Rong,li-Xian-he Bu, Joan

Ribs and Stuart R..Batten. Inorg.Chem.vol.45 (16) 2006, p.6129.

188. Singh, N.K., and Khushawala, S.K.; Ind. J. Chem.43 A (2004). P.1.

189. Zhong-Hai-Ni, Li.Fang Zhang, Chun-Huo Ge, Ai-Li-Cui, Hui-Zhong Kou

and JianZhuang Jiang; Inorg. Chem. Comu. 11(2008), p.94.

190. John T.York, Victor G.Young. Jr. and William B.Tolman.;

Inorg.Chem.vol.45 (10) 2006, p.4191.

191. Yuan – Zhu Zhang, ZheMing Wang and Song Gao.; Inorg. Chem.

45(2006). P.5447.

192. Takashiro Akitsu and Yasuaki Einaga.; Inorganica Chimica Acta. 361

(2008). P.36.

193. Long-Jiang, Xiano-Long Feng, Tong-Bulu and Song Geo; Inorg. Chem.

45(2006), p.5018.

194. .Murukan and K.Mohana. In 24th

annual conference of Indian council of

chemists P. 9, (2005).

195. Birendra Kumar and Brahameshwar; In 25th

annual conference of Indian

council of chemists P. 20 (2006).

55

196. Bayazeed H.Abdulla, Subhi A.Al-Jibori, Mohamad A. Abdullah and Talal

A K. Al-Allaf.; Asian J. Chem. 19(3) (2007), p. 2307.

197. Viktorya Skripacheva, Asiya Mustafina,Nataliya Rusakova, Vitaliya

Yanilkin, Nataliya Nastapova,Rustem Amirov, Vladimir Burilov,Rustem

Zairov, Svetlana Kost, Svetlana Solovieva,yuiry Korivin,Igor Antipin and

Alexander Konovalov.; Euoropean J. Inorg. Chemistry. Published online.21st

july 2008.

198. Jha, R.R., and Sahu, N.; Asian. J. Chem. 19(5) (2007), p.3681.

199. Sunil Kumar and Sonika. ; Asian. J. Chem. 19(5) (2007), p.3869.

200. Majed M.Hania.; Asian J. Chem. 19(3) (2007), p.1897.

201. Sha Raj Ali and K.T.Venkateshwarrao. In 25th

annual conference of Indian

council of chemists P.28 (2006).

56