joseph lister
Post on 07-Jan-2016
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In the 1800s, hospitals were often dangerous places. Many doctors didn't wear caps and gowns or wash their hands before they began to work. Doctors also hadn't discovered how to put people to sleep so a patient was usually awake during an operation. Some people died from the pain, but more often, they died from an infection, when germs got into their wounds. Back then, people believed that an infection was caused by something in the air.
Joseph Lister
“Father Of Modern Surgery"
The hospital environment has not always been a place of sterility and extreme cleanliness that is associated with it so readily today. Prior to the work of Joseph Lister, the hospital was a place to go to die, not to be cured. If an individual was able to survive the pain and torture of surgery without anesthesia, a postoperative infection would most certainly be their ultimate demise. Thanks to Joseph Lister, a hospital is now a place of healing and cleanliness, not one of death and filth.
Doctor Joseph Lister spent many years trying to find out how to prevent infection. In 1869, Dr. Lister invented a pump to spray carbolic acid into the air in operating theaters. It wasn't very pleasant to work with, but the chemical killed the bugs and kept patients safer. Soon, other hospitals began to use carbolic acid and more and more people survived their operations. Joseph Lister, bug buster, had made an important discovery that saved many lives.
Carbolic Acid is produced when phenol reacts with water…………….
+ H2O
OH O ─
+ H3O
+
Modern surgeons
Antiseptics
OH
CH3C
l
3HC
OH
OH
(CH2)5CH3
4 – chloro – 3,5 – dimethylphenol4 - hexylresorcinol
Because of Joseph Lister’s contribution to science, specifically in the field of medicine….The first company that produces health care and hygiene products was name after him to
give him recognition for his works.
PHENOL
What is phenol ?
OH
An “alcohol – like” compounds that have the hydroxyl group bound to a benzene ring.
Phenol is derived from the old name for benzene (phene), to include the suffix that indicates it possesses a hydroxyl group (ol).
CAUTION: The word phenol (C6H5-OH) is often confused with phenyl (C6H5-). Phenols are acidic and are important intermediates in the preparation of aryl ethers, C6H5-OR .
Phenol may be found as a translucent, clear, or light-pink crystalline mass; a white powder, or a clear liquid. It has a sweet, sharp odor or medicinal odor. Addition of small amount of water causes the solid to liquefy at room temperature. Phenol is used in many commercially available products including plastics, resins, fertilizers, paints, photographic developers, and some medicines.
NAME Melting point Boiling PointSolubility
g/100ml at 25°C
Phenol 41°C 182°C 11.3g
Methanol ─ 97°C 65°C Any amount
Description: Phenol is both a manufactured chemical and a natural substance. It is a colorless-to-white solid when pure. The commercial product is a liquid. Phenol has a distinct odor that is sickeningly sweet and tarry. You can taste and smell phenol at levels lower than those that are associated with harmful effects. Phenol evaporates more slowly than water, and a moderate amount can form a solution with water.Warning properties: pungent odor is usually adequate to warn of acute exposure ingestion can be fatal. Flammability: nonflammable
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Natural Phenols
Cloves
OH
OCH3
CH2 – CH ═ CH2
EUGENOL / Cloves
Nutmeg
OHOCH3
CH ═ CH – CH3
ISOEUGENOL/NUTMEG
Aniseed
OCH3
CH ═ CH – CH3
ANETHOLE
Vanilla
OHOCH3
H – C ═ OVANILLIN
Thyme
OH
CH – CH3
CH3
3HC
THYMOL / THYME MINT
C – O – CH3
O
OH
METHYL SALICYLATE
Synthetic Phenol Derivatives
OH C
CH3
CH3
CH3
OCH3
Butylated Hydroxy Anisole(BHA
)2 – t – butyl – 4 - methoxyphenol
OH CC
CH3
CH3
CH3
CH3
CH3
CH3
3HC
Butylated Hydroxy Toluene
(BHT)2,6 – di – t – butyl – 4 - methylphenol
Disinfectant
C – OH
O
OH
Salicylic Acid
OH
O - phenylphenol
CH2OH
Cl2 – benzyl – 4 - chlorophenol
Beverage preservative
Food preservative
Additive for coal tar/ asphalt modification
Dyes, Pigments & Colorants
Rubber & Plastic
Antioxidant
Aromatic Rules When a single hydrogen of the benzene ring is replaced by a
hydroxyl, the compound can be named as a derivative of benzene or simply PHENOL.
A number of phenol derivatives are known by common names that are also IUPAC – accepted and are used preferentially over other possibilities.
Compounds formed by replacing a hydrogen of benzene with more complex hydrocarbon group can be named by designating the benzene ring as substituent.
We called them phenyl group. When two groups are attached to a benzene ring, three isomeric
structures are possible. They can be designated by the prefixes ortho (o), meta (m), and para (p):
When two or more groups are attached to a benzene ring, their positions can be indicated by numbering the carbon atoms of the ring so as to obtain the lowest possible numbers for the attachment positions.
Group that comes first in alphabetical order is given the lower number.
OH
CH3
CH3
3HC
OH
CH3CH2
2ON
NO2
HO
C6H5
C6H5
C6H5
OH
Br
Cl
2,3,4 - triphenylphenol
2 – ethyl – 4,5 - dinitrophenol
3 – bromo – 5 – chlorophenol
3,4,5 - trimethylphenol
OH
OHOH
OH
OH
OH
OH
Phenol Cathecol
Resorcinol
Hydroquinone
OH
CH3
P – methylphenol
OH
OH
Br
Cl2 – bromo – 5 – chlorohydroquino
ne
OH
OHCH3CH2 5 – ethylresorcin
ol
OH
HO
NO2
2ON
3,5 - dinitrocathecol
Phenol Reactions
HalogenationNitrationSulfonationAkylationEther Formation
Halogenation
OH
+ Br2
U r ask 2 produce 2,4,6 - tribromophenol O
H Br
+ HBr
Then……… all u have 2 do is to continue the sequence of reaction 2 produce ur
desired product.
FeBr3
NitrationU r ask 2 produce m - nitrophenol
OH
+ HNO3
+ H2O
OH
NO2
20°CH2SO4
Sulfonation
+ SO3
H2So4
15 – 20 °C
OH OH SO3H
O – phenolsulfonic acid
TEMPERATURE VARY DEPENDING ON THE DESIRED POSITION.
100 °C FOR PARA POSITION
Alkylation
+ CH3 – C – CH3
CH3
Cl
OH
HNO3
C
CH3
CH3
CH3
OH
+ HCl
2 – t – butylphenol / O – t – butylphenol
IN THIS REACTION U WILL BE USING AN ACID CATALYST IT CAN BE HNO3, HF, HI, OR HCl.
Williamson synthesis/Ether
formation
OH
+ CH3 – CH2 – Br
NaOH
Δ
O CH2CH3
+ HBr
ethoxybenzene
Time 4 ur much
awaited Exercise…………
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