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Einstein Classes, Unit No. 102, 103, Vardhman Ring Road Plaza, Vikas Puri Extn., Outer Ring Road

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ORGANIC COMPOUNDCONTAINING OXYGEN

Sy l labus :

General methods of preparation, properties,reaction and uses.

ALCOHOLS, PHENOLS AND ETHERS

Alcohols : Identification of primary, secondary andtertiary alcohols; mechamism of dehydration.

Phenols : Acidic nature, electrophilic substitutionreactions : halogenration, nitration andsulphonation, Reimer - Tiemann reaction.

Ethers : Structure

Aldehyde and Ketones : Nature of carbonyl group;

Nucleophilic addition to >C = O group, relativereactivities of aldehydes and ketones; Importantreactions such as - Nucleophilic addition reactions(addition of HCN, NH

3 and its derivatives),

Grignard reagent; oxidation; reduction (Wolffkishner and Clemmensen); acidity of ? - hydrogen,aldol condensation, Cannizaro reaction, Haloformreaction; Chemical tests to distinguish betweenaldehydes and ketones.

Carboxylic Acids

Acidic strength and factors affecting it.


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C O N C E P T S (Monohydric Alcohols & Ether)

Alcohols :

C1A Physical Properties :

The lower alcohols are completely soluble in water but as the number of carbon atoms increases,solubility decreases. This solubility in water is due to intermolecular H-bonding between water andalcohols molecules due to their polar character.

Increase in C-chain increases organic part hence solubility in water decreases.

Isomeric 10, 20, 30 alcohols have solubility in order : 10 > 20 > 30.

C1B Method of preparation of Alcohols :

(i) Hydration of Alkenes :

42SOHdil

Intermediate is carbonium ion that can change to more stable carbanion ion by hydrideshift, alkyl or phenyl shift.

(ii) Hydrolysis of Alkyl Halides :

R – X + aq. NaOH (or H2O) R – OH + NaX (or HX)

Reaction can be 21 NNSorS .

(iii) Reduction of Carbonyl Compounds (including acid derivative) :

(a) OHRCHRCHO 2NaBHorLiAlH 44

10

(b) 44 NaBHorLiAlH

(c) Acid, acid halide, ester and anhydride are reduced to 10 alcohol.

(iv) Hydroboration and oxidation :

3223OH,OH

3223THFinBH

23 )OH(BOHCHCHCHB)CHCHCH(CHCHCH 223

The hydroboronation-oxidation (HBO) process gives product corresponding toanti-Markownikoff addition of H

2O to the carbon-carbon double bond.

(v) Oxymercuration-Demercuration :

OH

)OAc(Hg

2

2 4NaBH

The alcohol obtained corresponds to Markownikov’s addition of water to an Alkene.

(vi) (a) Through Grignard Reagent :

Addition of Grignard Reagent on carbonyl compounds followed by hydrolysisyields alcohols nature of which depends upon types of carbonyl compounds used.


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OH3 + H

2O

R1, R

2 can be H, alkyl or aryl but R

3 is not H.

(b) Grignard reagent with epoxide and after hydrolysis gives 10 alcohol for e.g.,

OH2

Practice Problems :

1. Propene, CH3 – CH = CH

2 can be converted into 1-propanol, Which of the reagent among the

following is ideal to affect the conversion :

(a) alkaline KMnO4

(b) B2H

6 and alkaline H

2O

2

(c) O3/Zn (d) OsO

4/CH

2Cl

2

(b)

2. Glycol may be obtained :

(a) by the oxidation of ethylene with cold, dilute, alkaline permanganate solution

(b) by the hydrolysis of ethylene bromide under reflux with aqueous sodium carbonatesolution

(c) by the hydrolysis of ethylene chlorohydrin on boiling with aqueous sodium bicarbonate

(d) by any of the above methods

(d)

3. Which of the following are the starting materials for the Grignard’s synthesis of tert. butyl alcohol

(a) CH3MgI + CH

3COCH

3(b) CH

3MgI + CH

3CHOHCH

3

(c) CH3CH

2MgBr + CH

3COCH

3(d) CH

3CH

2MgBr + CH

3CHO

(a)

[Answers : (1) b (2) d (3) a]

C2 Chemical Properties :

(i) Dehydration of Alcohol :

42SOH.conc

Alcohols leading to conjugated alkenes are more easily dehydrated then those of alcoholsleading to non-conjugated alkenes.

Dehydration of alcohol is in the order 30 > 20 > 10 as intermediate is carbocation.

(ii) Reaction with Halogen Acids :

R – OH + HX RX + H2O

Intermediate is carbonium ion. The order of reactivity of HX : HI > HBr > HCl for a givenalcohol.

(iii) Reaction with Phosphorous Halides and Thionyl Chloride :

3R – OH + PX3 3RX + H

3PO

3

(X = Br, I)

R – OH + SOCl2 RCl + SO

2 + HCl

(iv) Acidic Character of Alcohol :

RO – H + Na RO–Na+ + ½ H2


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alkoxide

The order of acidic character of alcohol with metal is :

CH3OH > 10 > 20 > 30.

The relative acidities is as follows :

RCOOH > C6H

5OH > H

2O > ROH > CH CH > NH

3 > RH

(v) Ester Formation (alcohol can act as a nucleophile also).

Thus reactivity of alcohols for given acid is in order :

CH3OH > 10 > 20 > 30

and those of acids for given alcohol is in order :

HCOOH > CH3COOH > RCH

2COOH > R

2CHCOOH > R

3CCOOH

(vi) Oxidation of Alcohol :

1. Using Cu

(a) 2Aldehyde

3C300

Cu

123 HCHOCHOHCHCH

00

(b) C300

Cu

0

(c) C300

Cu

0

2. Oxidation using KMnO4/K

2Cr

2O

7

(a) RCOOHOHRCHH)ii(

KMnO)i(2

4

(b)

(c) 72234 OCrKoracid,aceticglacialinCrO,KMnO

3. Other reagents used for oxidation :

(a) PCC (pyridinium chlorochromate) to oxidise 10 alcohols to aldehydes.

(b) MnO2 selectively oxidises the OH group of allylic and benylic 10 and 20

alcohols to give aldehydes and ketones respectively.

C3 Test to distinguish 10, 20 and 30 Acohols :

(a) Lucas Reagent (anhydrous ZnCl2/conc. HCl)

(b) Oxidation

(c) Victor Meyer Test


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Practice Problems :

1. Identify (Z) in the following reactions series :

)Y()X(EthanolKOH.AlcPBr3 )Z(

heat,OH

.temproom,SOH

2

42

(a) CH2 = CH

2(b) CH

3CH

2OH (c) CH

3CH

2OSO

3H (d) C

2H

5OC

2H

5

2. An organic compound gives hydrogen on reacting with sodium metal. It also gives iodoform test andforms an aldehyde of molecular formula C

2H

4O on oxidation with acidified dichromate. The

compound is :

(a) CH3OH (b) CH

3COOH (c) CH

3CHO (d) C

2H

5OH

3. The order of reactivity of the following alcohols,

towards conc. HCl is

(a) I > II > III > IV (b) I > III > II > IV

(c) IV > III > II > I (d) IV > III > I > II

[Answers : (1) b (2) d (3) c]

C4 Ethers

Nomenclature of Ethers :

Cyclic ethers can be named in severay ways :

In another system, a cyclic three membered ether is named as oxirane and a four membered ether iscalled oxetane.

C5 Methods of Preparation of Ether :

(a) Williamson Synthesis :

Example :

(i)


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(ii)

Discussion : Phenol in Williomson’s synthesis :

Because phenols are stronger acids than alcohols they can react with NaOH to change into sodiumphenoxide ion. But alcohols can be converted into sodium alkoxide ion by reaction with sodiummetal only.

[Alkyl halide used here can not be aryl halide as it does not undergo nucleophilic substitution easily]

R – X can be X = –Cl, –Br, I, – OSO3CH

3 etc.

(b) Ethers by Intermolecular Dehydration of Alcohols :

Alcohols can dehydrate to form alkenes.

10 Alcohols can also dehydrate to form ethers.

The formation of ether takes places by 2NS mechanism mainly, with one molecule acting as the

nucleophile and with another protonated molecules of the alcohol acting as the substrate.

Finally this method is not useful for the preparation of ether with 30 alcohol because they formalkene too easily. This method is not useful for the praparation of unsymmetrical ethers fromprimary alcohols because the reaction leads to a mixture of products.

(c) Ethers may be prepared by the addition of alcohols to alkenes in the presence of acid e.g.

Practice Problems :

1. Which route provides a better synthesis of ether :

(a) I (b) II (c) equal (d) none

[Answers : (1) b]

C6 Reactions of Ethers :

(a) Ethers are comparitavely unreactive compounds. The ether linkage are quite stabletowards bases, oxidizing agent, reducing agents. Ether can undergo just one kind ofreaction, cleavage by acids :

XRRXOHRRXHXRORHX

Reactivity of HX : HI > HBr > HCl


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Cleavage takes place only under quite vigourous conditions : concentrated acids (usually HI or HBr)and high temperature.

Oxygen of the ether is basic, like the oxygen of alcohol. The initial reaction between an ether and anacid is undoubtedly formation of the protonated ether.

Cleavage then involves the nucleophilic attack by halide ion on this protonated ether, withdisplacement of the weakly basic alcohol molecule.

As we might expect primary alkyl group tend to undergo 2NS and 30 tend to undergo 1N

S .

(b) Acid Hydrolysis : OHHC2OHHCOHC 5235252 .

(c) Acid Hydrolysis of Epoxide : OH3

(d) Formation of Halohydrin : HX

Practice Problems :

1. Ethoxy ethane does not react with

(a) HI (b) conc. H2SO

4(c) PCl

5(d) Na

2. An ether, (A) having molecular formula, C6H

14O, when treated with excess of HI produced two alkyl

iodides which on hydrolysis yield compounds (B) and (C). Oxidation of (B) gives an acid (D), whereasoxidation of (C) results in the formation of a mixed ketone, (E). Thus structures of (A) is

(a) (b) CH3CH

2CH

2CH

2OCH

2CH

3

(c) (d)

[Answers : (1) d (2) c]

Aldehydes & Ketones

C7A Physical Properties :

It has high dipole moment

Boiling point are lower than alcohols due to their inability to form intermolecular H-bonding.

B.Pt. are higher than corresponding alkanes due to dipole-dipole interaction.

Carbonyl group can form H-bond with H2O hence they are soluble in water to varying extent.


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C7B Method of Preparation :

1. Oxidation :

(a)

(b)

(c)

This oxidation is called as oppenauer oxidation.

2. Rossenmund Reduction :

3. [LiAlH (O-t-C4H

9)

3 or Lithium tri-t-butoxy Aluminium hydride]

4.

5. Hydrolysis of Gem-Dihalide

(a)

(b)

(c) ArCHOArCHClArCHOH

2heat,Cl

322

6. Hydration of Alkynes : Hydration of alkynes gives ketones (except CH CH which gives CH3CHO)

(a) CHOCHCHCH 3HgSO

H,OH

4

2

(b)33

HgSO

H,OH3 COCHCHCHCCH

4

2


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7. Hydroboration Oxidation :

Hydroboration of a non-terminal alkyne followed by oxidation of the intermediate yields a ketonebut terminal alkyne yield aldehyde.

8. Use of Grignard Reagent :

(a) With HCN aldehyde is formed.

(b) With RCN a ketone is formed.

9. With Esters

(a)

(b)

10. Decarboxylation of calcium salts of carboxylic acids :

11. Oxo Process :

2 CH3CH = CH

2 + CO + H

2 CH

3CH

2CH

2CHO +

[COH(CO)4] Cobal + Carbonyl hydride

12. Reduction of acid chloride with organocopper compounds :


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13. Friedel-Crafts Acylation :

(a)

(b)

14. From Cadmium and Lithium Salts :

1. 2RMgX + CdCl2 R – Cd – R + MgCl

2 + MgX

2

R – Cd – R + R’COCl RCOR’ + RCdCl

R should be 10 alkyl or aryl (–C6H

5)

15. Ozonylysis of Alkene (Zn/H+) Aldehyde/Ketone

C8 Chemical Properties :

1. Nucleophilic Addition to the Carbon-Oxygen Double bond :

The most characteristic reaction of aldehyde and ketone is nucleophilic addition to thecarbon-oxygen double bond.

General Reaction :

Relative reactivity of Aldehydes versus Ketones :

Aldehydes are more reactive than Ketones. There are two reasons for this, they are as follows :

1. Steric Factor 2. Electronic factor

1. Steric Factor : With one group being the small hydrogen atom, the central carbon of the tetrahedralproduct formed from the aldehyde is less crowded and the product is more stable.

With ketones two alkyl groups at the carbonyl carbon causes greater steric crowding in thetetrahedral product and make it less stable. Therefore small concentration is present at equilibrium.

2. Electronic Factor : Because alkyl group are electron releasing therefore aldehydes are more reactiveon electronic grounds as well. Aldehyde have one electron releasing alkyl group to stablise the partialpositive charge on the carbon atom of the carbonyl group. Whereas ketones have two alkyl groups.


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(a) Addition of cyanide :

(b) Addition derivatives of ammonia :

(i)

(ii) HCHO reacts with NH3 differently forming UROTROPINE [hexamethylene tetraamine].

6HCHO + 4NH3 (CH

2)

6N

4 + 4H

2O

H2N – G Product

H2N – OH Hydroxylamine = N – OH oxime

H2N – NH

2Hydrazine = N – NH

2Hydrazone

H2N – NHC

6H

5Phenylhydrazine = N – NHC

6H

5Phenylhydrazone

H2N – NHCOCH

2Semicarbazine = NNHCOCH

2Semicarbazone

(c) Addition of Alcohols : Acetal Formation

(i)

(ii)


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Important :

(d) Addition of Grignard reagents :

Formaldehyde with Grignard Reagent gives 10alcohol, all higher aldehydes with grignard reagentgive 20 alcohol and ketones with grignard reagent gives the 30 alcohol.

C9 Other Reactions of Aldehyde and Ketones :

(a) Oxidation :

(i) RCHO or ArCHO

Aldehydes (except) benzaldehyde reduce “Fehling’s Solution” (Cu2+ reduced to Cu+) which is analkaline solution of Cu2+ ion complexed with tetrarate ion.

(ii) Example : Tollen’s Test :

OH2NH4Ag2COOCHOH3)NH(Ag2CHOCH 23

mirrorSilver

3–

SolutionColourless

233

Fehling Solution OH2Cu2COOCHOH3Cu2CHOCH 2.PPtdRe

32

3

Tollen’s test is cheifly given by aldehydes. Tollen’s reagent does not attack carbon-carbon doublebond. Aldehyde also reduce benedict’s solution (Cu2+ complexed with citrate ion) to Cu+

(b) (i) Ketones with strong oxidants and at high temperature undergo cleavage of C-Cbond on either side of carbonyl group.

Carbonyl Group after bond cleavage goes with that alkyl group which is of smallersize.

(ii) Ketones are also oxidised from cleavage of bond by caro’s acid (H2SO

5) or

peroxybenzoic acid (C6H

5CO

3H) to esters. RRCOORRCO

]O[

SOH 52 [Bayer’ss

Villiger Oxidation]

(c) Haloform Test :

(i) Methylketones :


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(ii) Hypohalite NaOX (NaOH + X2) cannot only halogenate can also oxidise alcohols

(d) Reduction :

(a) Reduction to alcohol

(e) Reduction to hydrocarbons :

(f) Reductive Amination (Discussed under Amines)

(g) Cannizzaro reaction : In the presence of an concentrated base i.e. alkali, aldehydescontaining no -hydrogens undergo self oxidation and reduction to yield a mixture of analcohol.

(i)

(ii)

(h) Crossed Cannizzaro reaction :


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(i) Tischenko Reaction :

All aldehyde in presence of aluminium ethoxide, Al(OC2H5)

3 can be simultaneously oxidised

(to acid) and reduced (to alcohols) to form ester. This is called Tischenko reaction and isthus like cannizaro reaction.

(j) Distinction

Aldehyde and Ketones

S.No. Test RCHO RCOR

1. Schiffs magenta no. reactionreagent colour restored by

RCHO

2. Tollen’s reagent is reduced by RCHO is not reduced

3. Fehling’s solution is reduced by RCHO is not reduced(except C

6H

5CHO) -hydroxy, ketones

reudce Tollen’s reagent and Fehling’ssolution

Practice Problems :

1. Identify (Z) in the reaction series, )Y()X(CHCHHydrolysisHBr

22 )Z()NaOH

)excess(I 2

(a) C2H

5I (b) C

2H

5OH (c) CHI

3(d) CH

3CHO

2. A compound (X) of the formula C3H

8O yields a compound C

3H

6O on oxidation. To which of the

following class of compounds could (X) belong

(a) aldehyde (b) secondard alcohol

(c) alkene (d) tert. alcohol

3. Which statement is incorrect in the case of acetaldehyde and acetone

(a) both react with hydroxylamine

(b) both react with NaHSO3

(c) both react with hydrazine

(d) both reduce ammonical silver nitrate

4. Which of the following undergoes Cannizzaro’s reaction

(a) CH3CHO (b) CH

3CH

2CHO (c) (CH

3)

2CHCHO (d) HCHO

5. Urotropine is formed by the action of ammonia on

(a) acetaldehyde (b) formaldehyde (c) acetone (d) phenol

6. Hydrocarbons are formed when aldehydes and ketones are reacted with amalgamated zinc andconc. HCl. The reaction is called

(a) Cannizzaro’s reaction (b) Clemmensen’s reduction

(c) Rosenmund’s reaction (d) Tischenko reaction


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7. When acetaldehyde is treated with aluminium ethoxide, it forms

(a) ethyl acetate (b) ethyl alcohol

(c) acetic acid (d) methyl propionate

8. Chloretone is formed when chloroform reacts with

(a) formaldehyde (b) acetaldehyde (c) acetone (d) benzaldehyde

9. Which of the following reagent reacts differently with HCHO, CH3CHO and CH

3COCH

3

(a) HCN (b) NH2OH (c) C

6H

5NHNH

2(d) NH

3

10. In the following sequence of reactions, the end product is

()B()A(CaC ]O[SOH/HgOH2

422

2

)E()D()C( heat)OH(Ca 2

(a) acetaldehyde (b) formaldehyde (c) acetic acid (d) acetone

11. In the following sequence of reactions, the end product is

()A(CHHC]OH[

MgXCHSOH/Hg

2

3422

)C()B( ]O[

(a) acetaldehyde (b) isopropyl alcohol

(c) acetone (d) ethyl alcohol

12. In the following sequence of reactions, the end product is )B()A(CHOCH OHHCN3

2

(a) CH3COOH (b) CH

3CHOHCOOH

(c) CH3CH

2NH

2(d) CH

3CONH

2

13. A compound, C5H

10O, forms a phenyl hydrazone and gives negative Tollen’s and iodoform tests. The

compound on reduction gives n-pentane. The compound A is

(a) pentanal (b) pentanone-2 (c) pentanone-3 (d) amyl alcohol

14. The product Z in the series is

YXCHCH HydrolysisHBr22 Z

32

2

CONa

)excess(I

(a) C2H

5I (b) C

2H

5OH (c) CHI

3(d) CH

3CHO

15. If formaldehyde and KOH are treated together, we get

(a) methane (b) methanol (c) ethyl acetate (d) acetylene

16. The correct order of reactivity in nucleophilic addition reaction CH3CHO, CH

3COC

2H

5 and

CH3COCH

3 is

(a) CH3CHO > CH

3COCH

3 > CH

3COC

2H

5

(b) C2H

5COCH

3 > CH

3COCH

3 > CH

3CHO

(c) CH3COCH

3 > CH

3CHO > C

2H

5COCH

3

(d) CH3COCH

3 > C

2H

5COCH

3 > CH

3CHO

17. To distinguish between 2-pentanone and 3-pentanone which reagent can be used

(a) NaOH/I2

(b) Tollen’s reagent

(c) K2Cr

2O

7/H+ (d) Zn–Hg, HCl

18. CH3CH = CHCHO is oxidised to CH

3 – CH = CHCOOH, using oxidising agent as

(a) alkaline KMnO4

(b) K2Cr

2O

7/conc. H

2SO

4

(c) ammonical AgNO3

(d) dilute HNO3

19. m-chloro benzaldehyde on reaction with conc. KOH at room temperature gives

(a) potassium m-chloro benzoate and m-hydroxy benzaldehyde

(b) m-chloro benzyl alcohol and m-hydroxy benzaldehyde

(c) m-chloro benzyl alcohol and m-hydroxy benzyl alcohol

(d) m-chloro benzyl alcohol and potassium m-chloro benzoate


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20. The reagent which can be used to distinguish acetophenone from benzophenone is :

(a) 2, 4-dinitrophenyl hydrazine (b) benedict reagent

(c) I2 and Na

2CO

3(d) aqueous solution of NaHSO

3

21. Best starting material to synthesize 2-methyl-2-butenoic acid is

(a) (b) CH3CH

2CH

2CHO

(c) (d)

22. X and Y can be distinguished by :

(a) silver-mirror test(b) iodoform test (c) both (d) none

23. Which of the following will give haloform test

(a)3

||O

3 CClCCH (b) ICHCCH 2

OH|

3

(c) ClCHCCH 2

O||

3 (d) all

[Answers : (1) c (2) b (3) d (4) d (5) b (6) b (7) a (8) c (9) d (10) d (11) c (12) b (13) c (14) c (15) b(16) a (17) a (18) a (19) d (20) c (21) c (22) c (23) d]

Carboxylic Acids and Derivatives

C10 Common name of carboxylic acids :

1. CH3CH

2CH

2CH

2COOH valeric acid 2. oxalic acid

3. Malonic acid; 4. Succinic acid

5. maliec acid ; Fumaric acid

6. adipic acid


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7. or

8. 9. CH2 = CH – COOH (acrylic acid)

10. O-Toluic acid 11. Phathalic acid

12. Isophthalic acid 13. Terphthalic acid

14. Salicylic acid 15. Anthranilic acid

16. 17.

18.

19. CH3 – CH = CH – COOH (crotonic acid)

20. (Pyruvic acid)

C11 Methods of preparation of carboxylic acid :

(a) By acid hydrolysis of cyanidies

(b) By the use of Grigrand Reagent


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(c) By oxidation method

(i) Oxidation of alcohols (10)

(ii) Oxidation of aldehyde

(iii) Oxidation of ketones

Iodoform Test :

(d) Oxidation of alkenes and alkynes RCOOH2RCHCHRH/)ii(

KMnOAlkaline)i( 4

RCOOH2RCHCHROH)ii(

O)i(

2

3

Practice Problems :

1. Cyanohydrin of which of the following gives lactic acid on hydrolysis

(a) acetone (b) acetaldehyde (c) propanal (d) HCHO

[Answers : (1) b]

C12 Chemical Properties of Carboxylic Acids :

(a) Carboxylic acid undergo nucleophilic substitution reaction

(i) Formation of amide from carboxylic acid

(ii) Formation of Acyl chloride

(iii) Formation of esters

(b) Formation of anhydride :

(c) Schmidt reaction :

(d) HVZ reaction :

(e) Reduction of caboxylic acid : OHCHCHCOOHCH 23LiAlH

34

(f) Formatin of alkane : 4CaONaOH

3 CHCOOHCH

(g) Formatin of Salts : Ca)COOCH(COOHCH 23)OH(Ca

32

effect of heating on salts : 3323 COCHCHCa)COOCH(

(h) Kolbe electrolysis : 33

isElectrolys)ii(

KOH)i(3 CHCHCOOHCH

(i) Acidic character : OHCOCOONaCHCOOHCH 223NaHCO

33


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Practice Problems :

1. Which of the following will not undergo HVZ reaction

(a) 2, 2-dimethyl propanoic acid (b) propanoic acid

(c) acetic acid (d) 2-methyl propanoic acid

2. Amongst the acids (a) CH CCOOH (b) CH2 = CHCOOH and (c) CH

3CH

2COOH, the acid strength

follows the sequence

(a) (a) > (b) > (c) (b) (a) < (b) < (c) (c) (a) = (b) = (c) (d) (a) = (b) < (c)

3. )B()A(COOHCHCH KOH.Alc

P

Cl23

2 The compound (B) is

(a) CH3CH

2OH (b) CH

3CH

2CN

(c) CH2 = CHCOOH (d) CH

3CHClCOOH

4. Formic acid

(a) is immiscible with water

(b) reduces ammonical silver nitrate

(c) is a weak acid nearly three and a half times weaker than acetic acid

(d) is prepared by heating potassium formate

5. Strongest acid out of CH3CO

2H, CH

2 = CHCO

2H, —CO

2H

(a) CH3CO

2H (b) CH

2 = CHCO

2H

(c) —CO2H (d) equal Ka

[Answers : (1) a (2) a (3) c (4) b (5) c]

CARBOXYLIC ACID DERIVATIVES

C13A Structures : Closely related to the cabroxylic acids and to each other are a number of chemicalfamilies known as functional derivative of carboxylic acids : Acid chlorides, anhydrides, amides andesters. Acid chlorides, anhydrides, amides and esters. These derivatives are compounds in which the

–OH of a carboxylic group has been replaced by –Cl, –OOCR, –NH2 or RO

They all contain acyl group

C13B Physical properties : The presence of group makes the acid derivatives polar compounds.

Acid chlorides and anhydrides and esters have boiling point is same as of aldehydes and ketones ofcorresponding molcular weight.

Amides have quite high boiling points because they are capable of strong intermolecular hydrogenbonding.


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The borderline for solubility in water ranges from three to five carbons for the esters to five to sixcarbons for the amides. The acid derivatives are soluble in usual organic solvents.

Volatile esters have pleasant, rather chracteristic odours; they are often used in the praparation ofperfumes and artificial flavoring.

Acid chlorides have sharp, irritating odours, at least partly due to their ready hydrolysis to HCl andcarboxylic acids

C14A Nucleophilic acyl substitution :

Each derivative is nearly always prepared - directly or indirectly from carboxylic acids, and can bereadily converted into the carboxylic acid by simple hydrolysis.

The derivatives of carboxylic acids, like the acids themselves, contain the carbonyl group, .

Here, too, as in aldehydes and ketones, the carbonyl group performs two functions :

(a) It provides a site for nucleophilic attack

(b) It increases the acidity of hydrogents attached to the alpha carbon.

Acyl compounds i.e. Carboxylic acids and their derivatives, typically undergo nucleophilicsubstitution in which – OH, – Cl, – OOCR, or – OR is replaced by some other basic group.Substitution takes place much more readily than at a saturated carbon atom; many of thesesubstitution do not take at all in the absence of carbonyl group e.g. replacement of – NH

2 by – OH.

– W = – OH, – Cl, – OOCR, – NH2, – RO

Let us discuss now properties of acyl compounds.

Both electronic and steric factors make the carbonyl carbon suceptible to nucleophilic attack.

(a) The tendency of oxygen to acquire the negative charge.

(b) The relatively unhindered transition state leading from the trigonal reactant to thetetrahedral intermediate. These factors make acyl compounds, too suceptible tonucleophilic attack.

It is the second step of reaction that acyl compounds differ from aldehydes and ketones.

The tetrahedral intermediate from an aldehyde/ketone compound gains a proton and the result isaddition.

The tetrahedral intermediate from an acyl compound ejects the :W group, returning to a trigonalcompound and thus result in substitution.


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C15A Acid Chlorides : Acid chlorides are prepared from the corresponding acids by reaction with SOCl2,

PCl5 or PCl

3 as already discussed.

C15B Reactions : Acid chlorides are the most reactive of the derivatives of carboxylic acids.

1. Like other derivatives it also undergo nucleophilic substitution reaction. Chlorine is expelled aschloride and its place is taken by some other basic group.

(a) Conversion into acids, hydrolysis :

(b) Conversion into amides :

(c) Conversion into Esters :

Acid chloride is added in portions to a mixture of the hydroxy compound and a base usually aq.NaOH or pyridine. Base serves not only to neutrilize the HCl evolved but also to catalyze thereaction.

2. Formation of Ketones. Friedel - Craft’s acylation :

3. Formation of ketones, Reaction with organo copper compounds :

4. Formation of aldehydes by reduction : RCOCl or ArCOCl 3)tOBU(LiAlH

RCHO or ArCHO

1. Sodium acetate + acetyl chloride gives

(a) CH3COOH (b) sodium formate

(c) acetic anhydride (d) acetone

(c)

C16A Acid Anhydrides

Preparation :

(i) Acetic anhydride is prepared by the reaction of acetic acid with ketene CH2 = C = O, which

itself is prepared by high teperature dehydration of acetic acid.

(ii) In contrast to monocarboxylic acids, certain dicarboxylic acids yield anhydrides on simpleheating. In those cases where five or six membered ring is produced.


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(a)

(b)

Ring size is crucial : with adipic acid, e.g. anhydride formation would produce seven-membered ringand does not take place. Instead carbon dioxide is lost and cyclopentanone is produced (a fivemembered ring is formed) :

C16B Reactions of Acid Anhydrides :

(i) Conversion into acids. Hydrolysis :

Example :

(ii) Conversion into amides. Ammonolysis :

Example :

(iii) Conversion into esters :


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(iv) Formation of Ketone : Friedel craft acylation

Amides

C17A Preparation : In the laboratory method of preparation of amide includes its preparation from acidchloride with ammonia, acid anhydride with ammonia.

In industry they are prepared by heating ammonium salts of carboxylic acids.

C17B Reaction of Amides :

1. Hydrolysis :

2. Conversion into nitrile :

3. Conversion into imides :

Example :

4. Hoffmann degradation of amides :


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Practice Problems :

1. The end product in the followin series of reaction is

)C()B()A(COOHCH 523 OPheatNH3

(a) CH4

(b) CH3OH

(c) acetonitrile (d) ammonium acetate

2. In a reaction, CNHC)C()B()A( 52OPheatNH 523 (A), (B) and (C) are :

(a) CH3COOH, CH

3COONH

4 and CH

3CONH

2

(b) CH3COCl, CH

3CONH

2 and CH

3COONH

4

(c) C2H

5COOH, C

2H

5COONH

4 and C

2H

5CONH

2

(d) C2H

5COONH

4, C

2H

5CONH

2 and C

2H

5COOH

[Answers : (1) c (2) c]

Esters :

C18A Preparation of Esters :

1. From acids :

Reactivity of OHR is 10 > 20 > 30

similarly > 10 > 20 > 30

Example

2. From Acid Chloride or anhydride :

3. Formation of cyclic esters (Lactone)

A hydroxy acid is both alcohol and acid. In those cases where five or six membered ring can formintermolecular esterification occurs. Thus or hydroxy acid looses water spontaneously by yield ofcyclic ester known as lactone. Treatment with base (OH–) rapidly opens the lactone ring.


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C18B Reactions of Esters :

1 Conversion into acids and acid derivatives

2. Conversion into amides

CH3COOC

2H

5 + NH

3 CH

3CONH

2 + C

2H

5OH

Treatment of an ester with ammonia, generally in ethylalcohol solution yield the amides. Thisreaction involved the nucleophilic attack by a base, ammonia, on the electron-deficient carbon; the

alkoxy group, 'OR is replaced by – NH2.

3. Conversion into esters : Transesterfication :

Acid is H2SO

4 or dry HCl

Base alkoxide ion generally used.

4. Reactions with Grignard Reagent :

5. Reduction to alcohols :

(a) Catalytic hydrogenation : Hydrogenolysis

OH'ROHRCHH2RRCOOalcohol1

2C250

OCuCr,CuO2

00

42

(b) Chemical Reduction : OHROHRCHLiAlHRCOOR 2ether.Anhyd

4

6. Reaction with carbanions : Clasien Condensation :

R


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Example :

7. Crossed Clasien Condensation :

Like a crossed aldol condensation, a crossed clasien condensation is also possible only when one ofthe reactants has no -hydrogens and thus is incapable of undergoing self condensation.

PHENOLS

C19A Structure and Nomenclature of Phenols :

Compounds that have a hydroxyl group directly attached to benzene ring are called phenols. Thusphenol is specific name of hydroxy benzene

Compounds that have a hydroxyl group attached to a polycyclic benenoid ring are chemicallysimilar to phenols, but they are called napthols and phenanthrols, e.g.

C19B Physical Properties of Phenols : The presence of hydroxy groups in the molecules of phenols meansthat phenols are like alcohols in being able to form strong intermolecular hydrogen bonds.

This hydrogen bonding causes phenols to be associated and therefore to have higher boiling pointsthan hydrocarbons of the same molecular weight.


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C20A Synthesis of Phenols :

Laboratory Synthesis : The most important laboratory synthesis of phenols is by hydrolysis ofarenediazonium salts.

This method is highly versatile and the conditions required for the diazotisation step and thehydrolysis step are mild.

1. General Reaction :

Specific Example :

Industrial Synthesis :

2. Hydrolysis of Cholorobenzene (Dow Process) :

(The mechanism for the reaction probably involves benzyne intermediate)

3. Alkali Fusion of Sodium benzene sulfonate : Sodium benzene sulfonate is melted (fused) with so-dium hydroxide at 3500C to produce sodium phenoxide acidification then yields phenol.

4. From Cumene Hydroperoxide :

I

II This cumene is oxidized to cumene hydrolperoxide


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Finally, when treated with 10% sulfuric acid, cumene hydroperoxide undergoes a hydrolyticrearrangement that yields phenol and acetone.

C20B Chemical Properties of Phenol :

1. Reaction of Phenol as Acid : Strength of phenols as acids :

Although phenols are structurally similar to alcohols, they are much stronger acids. The pKa valuesof most alcohols are of the order of 18. However the pKa values of phenols are smaller than 11.

Let us compare two superficially similar compounds cyclohexanol ane phenol.

Although phenol is weak acid when compared with carboxylic acid such as acetic acid (pKa = 4.75)

phenol is much stronger than cyclohexanol by a factor of 8.

Phenols are more acidic than cyclohexanol because of following reasons :

Phenoxide ion is more resonance stabilized than phenol. Resonance structures of phenoxid ion donot involve charge separation. No resonance structure can be written for cyclohexanol and its anionof course. The benzene ring of phenol acts as if it were as electron withdrawing group when wecompare it with cyclohexanol. That causes –OH oxygen to be more positive.

Reason : Carbon atom that bears hydroxyl group in phenol is sp2 hybridized, whereas in cyclohexanolsp3 bybridised. Greater the S– characted more electronegative the carbon. Thus carbon of benzeneis more electronegative than cyclohexanol.

Because phenols are more acidic than water, the following reaction goes almost completion.

The reaction between cyclohexanol and NaOH does not occur to significant extent as H2O is stronger

acid than 1-wexanol.

Acidity order of Phenols :

(a) (b)


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(c) (d)

(e)

Distinguishing and separating phenols from alcohols and carboxylic acids :

1. Phenols dissolve in aqueous sodium hyroxide whereas most alcohols with six carbon atoms or moredo not. Thus we can distinguish them.

2. Alcohols with five carbon atoms are more or less soluble in NaOH but do not form appreciableamount of sodium alkoxide.

3. Most phenols are not solible in aqueous sodium bicarbonate, but carboxylic acids are soluble.

C21 Other reactions of the O – H Group of Phenols :

1. Phenols react with carboxylic acid anhydrides and acid chlorides to form esters.

Thest reactions are similar to alcoholic as we have already discussed in alcohols.

2. Phenols in the Williamson Synthesis :

Because phenols are more acidic than alcohols they can be converted to sodium phenoxide throughthe use of sodium hydroxide (rather than use of sodium metal, the reagent that convert alcohols toalkoxide ion).

(a) General Reaction : NaXArORaNArOArOH]I,Br,ClX[

XRNaOH

(b) Cleavage of Alkyl-Aryl Ether :

RX.rxnnoOHHCROHCHX

56heat

HX.conc56

3. Reactions of the Benzene ring of Phenol :

(a) Bromination : The hydroxyl group is a powerful activating group and an ortho-paradirector in electrophilic substitution. Phenol itself react with Br

2 in aqueous solution to

yield 2, 4, 6-tribromophenol. Note that a Lewis acid is not required for the bromination of


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this highly activated ring.

(b) Monobromination of phenol can be achieved by carrying out the reaction in carbondisulfide (CS

2) at low temperature. Conditions that reduce the electrophilic activity of

bromine. The major product is the para isomer.

4. (a) Nitration : Phenol react with dilute nitric acid to yield a mixture o- and p-nitrophenol

Although the yield is relatively low (because of oxidation of ring). The ortho and para isomers can beseparated by steam distillation. o-Nitrophenol is more volatile isomer because its intramolecularhydrogen bonding. p-Nitrophenol is less volatile because intermolecular H-bonding causingassociation among molecules. Thus o-nitrophenol passes over steam and p-Nitrophenol remain inthe distillation flask.

(b)


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5. Sulfonation : Phenol reacts with concentrated sulfuric acid to yield mainly o-sulphonated product ifthe reaction is carried out at 250C and mainly the para substituted product if the reaction is at 1000C.

6. Kolbe’s Reaction : The phenoxide ion is even more suceptible to electrophilic aromatic substitution,then phenol itself.

High reactivity of phenoxide ion is used in a reaction called as kolbe reaction. In kolbe reactioncarbon dioxide act as the electrophile.

Reaction of salicylic acid with acetic anyhydride yields widely used pain reliver aspirin.

7. The Clasien rearrangement :

Clasien rearrangement can also take place when allyl vinyl ether are present

8. Diel Alder reaction is also pericyclic reaction :

9. Quinones : Oxidation of hydroquinone gives quinone


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10. Reimer-Tiemann Reaction :

11. Fries rearrangement :

Rearrangement involves RCO+, which then attacks the ring.Practice Problems :

1. When phenol is distilled with zinc dust, the main product is(a) biphenyl (b) benzene(c) benzaldehyde (d) phenolphtalein

2. When sodium benzene sulphonate is fused with sodium hydroxide (solid), the product formed is(a) benzene (b) phenol(c) benzene triphenol (d) none of these

3. Which of the following acids is strongest(a) C

6H

5SO

3H (b) CH

3COOH (c) C

6H

5COOH (d) (COOH)

2

4. Phenol is less acidic then(a) p-nitrophenol (b) ethanol(c) cresol (d) benzyl alcohol

5. Cumene 2

2

O)i(

H,OH)ii( (X) and (Y)

(X) and (Y) respectively are(a) toluene, propene (b) toluene, propylchloride(c) phenol, acetone (d) phenol, acetaldehyde

6. In the following compounds

the order of acidity is(a) III > IV > I > II (b) I > IV > III > II(c) II > I > III > IV (d) IV > III > I > II

7. When phenol reacts with benzene diazonium chloride, the product obtained as(a) phenyl hydrazine (b) p-amino azobenzene(c) phenol hydroxylamine (d) p-hydroxy azobenzene

8. )B()A(PhenolHNO.Conc

60at

SOH.Conc

Zinc

ondistillati

3

042 )C()

Zn

NaOH . In the above reaction, compounds (A),

(B) and (C) are(a) benzene, nitrobenzene and aniline(b) benzene, dinitrobenzene and m-nitroaniline(c) toluene, nitrobenzene and m-toluidine(d) benzene, nitrobenzene and hydrazobenzene[Answers : (1) b (2) b (3) a (4) a (5) c (6) d (7) d (8) d]


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INITIAL STEP EXERCISE

1. Identify (Z) in the series,

)Y()X(OHHC Br

C170

SOH.Conc73

2

0

42

)Z(KOH.Alc

ofExcess

(a)

(b)

(c) CH3 – C CH

(d)

2. When ethyl benzoate is hydrolysed with aqueousalkali, the products present in the medium are

(a) C6H

5COOH and C

2H

5OH

(b) C6H

5COOH and C

2H

5O—

(c) C6H

5COO— and C

2H

5OH

(d) C6H

5COO— and C

2H

5O—

3. How many isomers of C5H

11OH will be primary

alcohols :

(a) 5 (b) 4

(c) 3 (d) 2

4. An alcohol on oxidation is found to give CH3COOH

and CH3CH

2COOH. The structure of the alcohol is

(a) CH3CH

2CH

2OH

(b) CH3CH

2CH(OH)CH

3

(c) CH3CH(OH)CH

2CH

2CH

3

(d) (CH3)

2C(OH)CH

2CH

3

5. Which aromatic acid among the following is weakerthan simple benzoic acid

(a) (b)

(c) (d)

6. In the following sequence of reactions, the endproduct is

)B()A(CHOCHheat

agentgDehydratin

alkalimild

onCondensati3

(a) aldol

(b) crotonaldehyde

(c) paraldehyde

(d) metaldehyde

7. Which of the following reaction is a condensationreaction

(a) HCHO Paraformaldehyde

(b) CH3CHO Paraldehyde

(c) CH3COCH

3 Mesityl oxide

(d) CH2 = CH

2 Polyethylene

8. A compound A has molecular formula C2Cl

3OH. It

reduces Fehling’s solution and on oxidation gives amonocarboxylic acid. A is obtained by the action ofCl

2 on ethyl alcohol. The compound A is

(a) chloroform

(b) chloral

(c) trichloro ethanol

(d) trichloro acetic acid

9. Salicylic acid on heating with soda lime forms

(a) benzene (b) phenol

(c) benzyl alcohol (d) benzoic acid

10. Out of butane, butanol-1, butanal and butanone,the decreasing order of their boiling point is

(a) butane > butanol > butanal > butanone

(b) butanol > butane > butanal > butanone

(c) butanone > butanal > butanol > butane

(d) butanol > butanal > butanone > butane

11. The alkene which on ozonolysis yields only acetoneis

(a) CH2 = CH

2

(b) CH3 – CH = CH

2

(c) (CH3)

2C = C(CH

3)

2

(d) CH3CH = CHCH

3

12. In the reaction CH3CHO + HCN CH

3CHOHCN,

a chiral centre is produced. The product is

(a) meso compound

(b) laevorotatory

(c) dextrorotatory

(d) racemic mixture


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13. Leaving tendency of the following in increasingorder :

(a) VI < V < III < II < IV < I

(b) I < II < III < VI < V < IV

(c) I < III < V < II < IV < VI

(d) can’t be decided

14. Formylchloride has not been prepared so far. Whichcan function as formylchloride in formylation

(a) HCHO + HCl

(b) HCOOCH3 + HCl

(c) CO + HCl

(d) HCONH2 + HCl

15. Formic acid is obtained when

(a) calcium acetate is heated with conc.H

2SO

4

(b) glycerol is heated with oxalic acid

(c) acetaldehyde is oxidised with K2Cr

2O

7

and H2SO

4

(d) calcium formate is heated with calciumacetate

16. Formic acid and formaldehyde can be distinguishedby treating with

(a) Benedict’s solution

(b) Tollen’s reagent

(c) Fehling’s solution

(d) NaHCO3

17. In the reaction

)C()B()A(OHHC HydrolysisKCNPI52

3

The product (C) is

(a) acetic acid (b) formic acid

(c) oxalic acid (d) propionic acid

18. RCOOH + N3H .)conc(SOH 42 RNH

2 + CO

2 + N

2

The above reaction is called

(a) HVZ reaction

(b) Hunsdiecker reaction

(c) Schmidt reaction

(d) Decarboxylation reaction

19. Which of the following reactions is expected toreadily give a hydrocarbon product in good yield

(a) isElectrolysRCOOK

(b) 2BrRCOOAg

(c)hv

Cl33

2CHCH

(d) OHHC33

52ClC)CH(

20. When propionic acid is treated with aqueousNaHCO

3, CO

2 is liberated. The ‘C’ of CO

2 comes

from

(a) methyl group

(b) carboxylic acid group

(c) methylene group

(d) bicarbonate

21. Which will liberate ammonia when boiled withNaOH solution

(a) ethyl amine (b) acetamide

(c) aniline (d) all

22. Acetyl chloride is not obtained from acetic acid bythe action of

(a) CHCl3

(b) SOCl2

(c) PCl3

(d) PCl5

23. Main product of the reaction CH3CONH

2 +

HNO2 is

(a) CH3NH

2(b) CH

3CH

2NH

2

(c) CH3COOH (d) CH

3OH

24. Urea is a

(a) monobasic acid (b) dibasic acid

(c) monoacid base (d) diacid base

25. 2CH3CHO 352 )HOC(Al

CH3COOCH

2CH

3. This

reaction is called

(a) Cannizzaro’s reaction

(b) Aldol condensation

(c) Claisen’s reaction

(d) Tischenko reaction

26. Explain the reactivity of acyl compounds in theorder

(a) acid chloride > amide > anhydride >ester

(b) acid chloride > anhydride > ester > amide

(c) ester > acid chloride > anhydride > amide

(d) ester > anhydride > acid chloride > amide


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27. Artificial oil of bitter almonds or oil of Mirabane isthe name given to

(a) chlorobenzene (b) benzaldehyde

(c) aniline (d) nitrobenzene

28. Which does not have a carboxyl group

(a) picric acid (b) ethanoic acid

(c) aspirin (d) benzoic acid

29. Phenols do not react with

(a) sodium bicarbonate

(b) sodium hydroxide

(c) potassium hydroxide

(d) ferric chloride

30. In the reaction,

)B()A(ClCHHC23 )NO(Cu

OxidationNaOH.Aq256 ,

(B) is

(a) benzoic acid (b) phenol

(c) toluene (d) benzaldehyde

31. The reaction involving condensation of acetic an-hydride with an aromatic aldehyde by a carboxy-late ion is an example of

(a) aldol condensation

(b) benzoin condensation

(c) Perkin reaction

(d) Wurtz reaction

32. Benzaldehyde when refluxed with aqueous alcoholicKCN forms

(a) benzoin

(b) benzene

(c) phenyl cyanide

(d) phenyl isocyanide

33. The reaction,

C6H

5CHO + CH

3CHO C

6H

5CH = CHCHO

is called :

(a) benzoin condensation

(b) Claisen condensation

(c) Perkin reaction

(d) Cannizzaro’s reaction

34. Cannizzaro’s reaction is not given by

(a) trimethyl acetaldehyde

(b) acetaldehyde

(c) benzaldehyde

(d) formaldehyde

35. In the following groups,

)IV(32

)III(2

)II()I(CFSO,MeOSO,OMe,OAc

the order of leaving group ability is

(a) I > II > III > IV

(b) IV > III > I > II

(c) III > II > I > IV

(d) II > III > IV > I

36. Benzyl alcohol is obtained from benzaldehyde by

(a) Wurtz reaction

(b) Cannizzaro’s reaction

(c) Perkin reaction

(d) Claisen reaction

37. C6H

6 + CO + HCl 3AlCl.Anhyd

(X) + HCl

The compound (X) is

(a) C6H

5CHO (b) C

6H

5COOH

(c) C6H

5CH

2Cl (d) C

6H

5CH

3

38. Which of the following is the weakest acid

(a) benzene sulphonic acid

(b) benzoic acid

(c) benzyl alcohol

(d) phenol

39. In the Cannizzaro’s reaction given below

22OH PhCOOHCHPhCHOPh2

the slowest step is

(a) attack of OH— at the carbonyl group

(b) the transfer of hydride to the carbonylgroup

(c) the abstraction of proton from thecarboxylic acid

(d) the deprotonation of Ph–CH2OH

40. 356.)aq(NaOH

ClOCCH56 OOCCHHCOHHC 3

The above reaction is an example of

(a) acetylation

(b) benzoylation

(c) Schotten-Baumann reaction

(d) Reimer-Tiemann reaction

41. Phenol on standing in air develops a red colour dueto formation of

(a) cyclohexane (b) resorcinol

(c) phenoquinone (d) quinol

42. Benzoic acid gives benzene on being heated with Xand phenol gives benzene on being heated with Y.Therefore X and Y are respectively

(a) soda lime and copper

(b) zinc dust and sodium hydroxide

(c) zinc dust and soda lime

(d) soda lime and zinc dust


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43. Phenol

H)ii(

NaOH/CHCl)i( 3 Salicyladehyde

This reaction is known as

(a) Gattermann aldehyde synthesis

(b) Duff reaction

(c) Perkin reaction

(d) Reimer-Tiemann reaction

44. Phenol on treatment with dil HNO3 gives

(a) picric acid

(b) o- and p-nitro phenols

(c) o- and m-nitro phenols

(d) p- and m- nitro phenols

FINAL STEP EXERCISE

1. A natural compound (X), C4H

8O

2, reduces Fehling’s

solution, liberates hydrogen when treated withsodium metal and gives a positive iodoform test.The structure of (X) is

(a) CH3CHOHCH

2CHO

(b) HOCH2CH

2CHO

(c) CH3COCH

2CHO

(d) CH3COCH

2CH

2OH

2. In a cannizzaro’s reaction, the intermediate that willbe the best hydride donar is

(a)

(b)

(c)

(d)

3. CH3CH = CH

2

4

22

NaBD

OH/OH product X

X is :

(a)

(b)

(c)

(d) none is correct

4. ocannizzair X and YY

(Y is alcohol, D is deuterium)

X and Y will have structure :

(a)

(b)

(c)

(d) none is correct

5. Consider reduction of 2-butanone

Abutanone2BOH

NaBD

OD

NaBD

2

4

2

4

A, B and C are :

(a) in all cases


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(c) propane

(d) ethyl methyl ether

8. The major product obtained when 3-phenyl-1,2-propane-diol is heated with H

2SO

4 is

(a) C6H

5 – CH

2 – CO – CH

3

(b) C6H

5 – CH

2 – CH

2 – CHO

(c) C6H

5 – CH

2 – CH = CH

2

(d)

9. A carbonyl compound with molecular weight 86,does not reduce Fehling’s solution but formscrystalline bisulphite derivatives and givesiodoform test. The possible compounds can be

(a) 2-pentanone and 3-pentanone

(b) 2-pentanone and 3-methyl-2-butanone

(c) 2-pentanone and pentanal

(d) 3-pentanone and 3-methyl-2-butanone

10. In the Cannizzaro’s reaction given below,

PhCOOOHPhCHCHOPh2 2OH

the slowest step is

(a) the attack of OH— at the carbonyl group

(b) the transfer of hydride to the carbonylgroup

(c) the abstraction of proton from thecarboxylic acid

(d) the deprotonation of Ph–CH2OH

11. The reaction of with a mixture of

Br2 and KOH gives R — NH

2 as a product. The

intermediates involved in this reaction are

(a)

(b) R — N = C = O

(c) R — NHBr

(d)

(b) ,

,

(c) ,

,

(d) in all cases

6. The reaction of CH3CH = CH — —OH

with HBr gives :

(a) CH3CHBrCH

2 — —OH

(b) CH3CH

2CHBr— —OH

(c) CH3CHBrCH

2— —Br

(d) CH3CH

2CHBr— —Br

7. The product (D) in the following sequence of reac-tion is :

()B()A(HC Na)aq(NaOHHBr42

)D()C( ICH3

(a) butane

(b) ethane


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COO – 38

12. Which of the following carboxylic acid undergodecarboxylation easily

(a) C6H

5COCH

2COOH

(b) C6H

5COCOOH

(c)

(d)

ANSWERS (FINAL STEP EXERCISE)

1. a

2. c

3. b

4. a

5. b

6. b

7. d

8. d

9. b

10. b

11. b

12. a

ANSWERS (INITIAL STEPEXERCISE)

12. d

13. a

14. c

15. b

16. d

17. d

18. c

19. a

20. d

21. b

22. a

1. c

2. c

3. b

4. c

5. c

6. b

7. c

8. b

9. b

10. d

11. c

23. c

24. c

25. d

26. b

27. d

28. a

29. a

30. d

31. c

32. a

33. b

34. b

35. b

36. b

37. a

38. c

39. b

40. a

41. c

42. d

43. d

44. b


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AIEEE ANALYSIS [2003]

4. During dehydration of alcohols to alkenes byheating with conc. H

2 SO

4 the initiation step is

(a) formation of an ester

(b) protonation of alcohol molecule

(c) formation of carbocation

(d) elimination of water

5. An ether is more volatile than an alcohol havingthe same molecular formula. This is due to

(a) inter-molecular hydrogen bonding inalcohols

(b) dipolar character of ethers

(c) alcohols having resonance structures

(d) inter-molecular hydrogen bonding inethers

6. When CH2 = CH — COOH is reduced with LiAlH

4,

the compound obtained will be

(a) CH3 – CH

2 – CHO

(b) CH3 – CH

2 – COOH

(c) CH2 = CH – CH

2OH

(d) CH3 – CH

2 – CH

2OH


1. BACOOHCHCHKOH.alc

Pred

Cl23

2 what is

B ?

(a) CH3CH

2COCl

(b) ClCH2CH

2COOH

(c) CH3CH

2CHO

(d) CH2 = CHCOOH

2. On vigorous oxidation by permanganate solution,

(CH3)

2C = CH – CH

2 – CHO gives

(a)

(b)

(c)

(d)

3. The reaction

OHC)CH(BrC)CH( 33OH

332

(a) Displacement reaction

(b) elimination reaction

(c) substitution reaction

(d) free radical reaction

AIEEE ANALYSIS [2004/2005/2006]

7. For which of the following parameters thestructural isomers C

2H

5OH and CH

3OCH

3 would

be expected to have the same values ?(Assume ideal behaviour)(a) heat of vaporisation(b) vapour pressure at the same temperature(c) boiling points(d) gaseous densities at the same

temperature and pressure[2004]

8. Rate of the reaction

is fastest when Z is(a) Cl (b) NH

2

(c) OC2H

5(d) OCOCH

3

[2004]9. Consider the acidity of the carboxylic acids

(i) PhCOOH(ii) o-NO

2C

6H

4COOH

(iii) p-NO2C

6H

4COOH

(iv) m-NO2C

6H

4COOH

Which of the following order is correct ?(a) i > ii > iii > iv (b) ii > iv > iii > i(c) ii > iv > i > iii (d) ii > iii > iv > i

[2004]


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COO – 40

16. The decreasing order of nucleophilicity among thenucleophiles

(I)

(II) CH3O–

(III) CN–

(IV)

(a) (I), (II), (III), (IV)(b) (IV), (III), (II), (I)(c) (II), (III), (I), (IV)(d) (III), (II), (I), (IV)

[2005]17. The reaction

is fastest when X is(a) Cl (b) NH

2

(c) OC2H

5(d) OCOR

[2005]18. Reaction of cyclohexanone with dimethyl-amine in

the presence of catalytic amount of an acid forms acompound is water during the reaction iscontinuously removed. The compound formed isgenerally known as(a) a Schiff’s base (b) an enamine(c) an imine (d) an amine

[2005]19. p-cresol reacts with chloroform in alkaline medium

to give the compound A which adds hydrogencyanide to form, the compound B. The latter onacidic hydrolysis gives chiral carboxylic acid. Thestructure of the carboxylic axid is

(a)

(b)

10. On mixing ethyl acetate with aqueous sodiumchloride, the composition of the resultant solutionis(a) CH

3COOC

2H

5 + NaCl

(b) CH3COONa + C

2H

5OH

(c) CH3COCl + C

2H

5OH + NaOH

(d) CH3Cl + C

2H

5COONa

[2004]11. Acetyle bromide reacts with excess of CH

3MgI

followed by treatment with a saturated solution ofNH

4Cl gives

(a) acetone(b) acetamide(c) 2-methyl-2-propanol(d) acetyl iodide

[2004]12. Which one of the following is reduced with zinc and

hydrochloric acid to give the correspondinghydrocarbon ?(a) ethyl acetate (b) acetic acid(c) acetamide (d) butan-2-one

[2004]13. Which one of the following undergoes reaction with

50% sodium hydroxide solution to give thecorresponding alcohol and acid ?(a) phenol (b) benzaldehyde(c) butanol (d) benzoic acid

[2004]14. Among the following compounds which can be

dehydrated very easily is(a) CH

3CH

2CH

2CH

2CH

2OH

(b)

(c)

(d)

[2004]15. The best reagent to convert pent-3-en-2-ol into

pent-3-en-2-one is(a) Acidic permanganate(b) Acidic dichromate(c) Chromic anhydride in glacial acetic acid(d) Pyridinium chloro-chromate

[2005]


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COO – 41


25. The compound formed as a result of oxidation ofethyl benzene by KMnO

4 is

(a) benzoic acid (b) benzyl alcohol

(c) benzophenone (d) acetophenone

26. In the following sequence of reactions,

DC

BAOHCHCH

OH

HCHO

ether

MgIP23

2

2

the compound ‘D’ is :

(a) n-propyl alcohol

(b) propanal

(c) butanal

(d) n-butyl alcohol

(c)

(d)

[2005]20. The increasing order of the rate of HCN addition

to compounds(A) HCHO, (B) CH

3COCH

3, (C) PhCOCH

3, and

(D) PhCOPh is(a) C < D < B < A (b) A < B < C < D(c) D < B < C < A (d) D < C < B < A

[2006]21. Phenyl magnesium bromide reacts with methanol

to give(a) a mixture of phenol and Mg(Me)Br(b) a mixture of anisole and Mg(OH)Br(c) a mixture of benzene and Mg(OMe)Br(d) a mixture of toluene and Mg(OH)Br

[2006]22. Among the following the one that give positive

iodoform test upon reaction with I2 and NaOH is

(a) PhCHOHCH3

(b) CH3CH

2CH(OH)CH

2CH

3

(c) C6H

5CH

2CH

2OH

(d)

[2006]

23. + CHCl3 + NaOH

The electrophile involved in the above reaction is

(a) formly cation )HOC(

(b) dichloromethyl cation )HClC( 2

(c) dichlorocarbene ( : CCl2)

(d) trichloromethyl anion

[2006]24. The structure of the compound that gives a

tribromo derivative on treatment with brominewater is

(a) (b)

(c) (d)

[2006]

ANSWERS AIEEE ANALYSIS

1. d 10. d 19. c

2. b 11. a 20. c

3. d 12. a 21. d

4. a 13. c 22. d

5. b 14. c 23. b

6. c 15. d 24. b

7. a 16. d 25. c

8. a 17. c 26. b

9. a 18. a


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COO – 42

TEST YOURSELF

1. In alcohol 10, 20 and 30 cann’t be distinguish by

(a) Catalyst dehydrogenration

(b) Victor meyer’s test

(c) Lucas reagent test

(d) can be distinguish by all

2. The number of isomers represented by molecularformula C

4H

10O is

(a) 3 (b) 4

(c) 7 (d) 10

3. LiAlH4 converts acetic acid into

(a) acetaldehyde (b) ethane

(c) ethyl alcohol (d) methyl alcohol

4. RONa + NaXRRORX is

(a) Wurtz reaction

(b) Williamson synthesis

(c) Reimer-tiemer reaction

(d) Tischenko reaction

5. The ether . When

treated with cold HI produces

(a) 2C6H

5CH

2I

(b) 2C6H

5OH

(c) C6H

5I and C

6H

5CH

2OH

(d) C6H

5CH

2I and C

6H

5OH

6. General formula of both aldehydes and ketones is

(a) CnH

2n + 2O (b) C

nH

2nO

(c) CnH

2n – 2O (d) C

nH

2n + 4O

7. The appropriate reagent for the followingtransformation is :

(a) Zn(Hg)/HCl (b) NH2NH

2/OH–

(c) H2/Ni– (d) NaBH

4

8. The Cannizzaro’s reaction is not given by

(a) trimethyl acetaldehyde

(b) acetaldehyde

(c) benzaldehyde

(d) formaldehyde

ANSWERS

1. d

2. c

3. c

4. b

5. d

6. b

7. b

8. b

9. c

10. c

9. )B()A(XMgRhydrolysisCHOCH3 .

Compound B in above sequence of reaction is

(a) Carboxylic acid

(b) Primary alcohol

(c) Secondary alcohol

(d) Tertiary alcohol

10. The reaction,

222.Conc

SOH3 NCORNHHNRCOOH 42

is called

(a) HVZ reaction

(b) Hoffmann’s reaction

(c) Schmidt reaction

(d) Decarboxylation reaction

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