carboxylic acid analysis, synthesis and other

Carboxylic Acid

Analys is , synthesis and other parts

Chemistry for Biologist ISection-01

Course Instructor: Mohammad Manzur Sharif Sayeem.

Submitted by

S. M. Jahid Mostofa

ID: 2015-1-77-033

Analysis of carboxylic acids

Litmus test: The blue litmus turn into red.

Sodium bicarbonate test: When add sodium bicarbonate in the solution , a small

bubbles of gas produced.

Analysis of carboxylic acidsHigher boiling points than similar alcohols,

due to dimer formation.

Acetic acid

Analysis of carboxylic acids

• Carboxylic acids are obviously acidic.• Stronger acids than alcohols, but weaker than

mineral acids.• Will react with NaOH to give metal

carboxylates.

Carboxylic acids: Synthesis Oxidation of primary alcohols

Cleavage of an alkenes with hot KMnO4 produces a carboxylic acid if there is a hydrogen on the double-bonded carbon.

Cleavage of an alkynes by ozonolysis.

Oxidation of aromatic compound.

Carbonation of Grignard reagents

Hydrolysis of nitriles.

Carboxylic acids: Synthesis1. oxidation of 1o alcohols:

CH3CH2CH2CH2-OH + CrO3 CH3CH2CH2COOH n-butyl alcohol butyric acid

1-butanol butanoic acid

CH3 CH3

CH3CHCH2-OH + KMnO4 CH3CHCOOH isobutyl alcohol isobutyric acid

2-methyl-1-propanol` 2-methylpropanoic acid

These oxidations are best performed using chromic acid (made from Na2Cr2O7 in H2SO4). Potassium permanganate can be used but gives lower yields.

Carboxylic acids: SynthesisOxidation of Aromatic Compounds

• Benzene does not react with KMnO4.• Alkyl groups on the ring (-R) are readily

oxidized though.• One product for all reactions.

R

+ KMnO4

O

OH

CH3

CH3

H3C

CH2CH3

KMnO4, heat

KMnO4, heat

KMnO4, heat

COOH

COOH

HOOC

COOH

toluene benzoic acid

p-xylene terephthalic acid

ethylbenzene benzoic acid

+ CO2

note: aromatic acids only!

Carboxylic acids: SynthesisOxidation of Aromatic Compounds

Grignard Synthesis

Grignard reagent + CO2 yields a carboxylate salt.

CH3CH3CHCH2MgBr

CH3CO O CH3CH3CHCH2COO

-MgBr

+

CH3H

+

CH3CH3CHCH2COOH

CH3

Carbonation of Grignard reagent:

R-X RMgX RCOOMgX RCOOH

Mg CO2 H+

CH3CH2CH2-Br CH3CH2CH2MgBr CH3CH2CH2COOHn-propyl bromide butyric acid

Mg CO2 H+

C

O

O

RMgX + R CO

O-+ +MgX

H+

R CO

OH

Carboxylic acids: Synthesis

CH3

Br

Mg

CH3

MgBr

CO2 H+

CH3

COOH

p-toluic acid

CH3

Br2, hvCH2Br

MgCH2MgBr

CO2

H+

CH2 COOH

phenylacetic acid

Carboxylic acids: Synthesis

Carboxylic acids: Synthesis Hydrolysis of Nitriles

Basic or acidic hydrolysis of a nitrile produces a carboxylic acid.

BrNaCN

CNH

+

H2O

COOH

=>

R-X + NaCN R-CN + H+, H2O, heat RCOOH1o alkyl halide

H2O, H+

R-CN R-COOH heat

H2O, OH-

R-CN R-COO- + H+ R-COOH heat

Adds one more carbon to the chain.R-X must be 1o or CH3!

Carboxylic acids: Synthesis

Uses for Carboxylic Acids

• Used to preserve foods because it kills bacteria that causes food to spoil

• Used as pain killers in different parts of Europe

• Used in latex paint• Used in adhesives

CARBOXYLIC ACID

NEGATIVE EFFECTS

Believe It or NotOkay, it’s really not that unbelievable

but hey...… give us a break!

Believe It or NotDid you know…

Some forms of Carboxylic Acid are used as an illegal

depressant in some European countries.

Did you know…The burn in your side when you run a lot is

caused by Lactic acid (a Carboxylic Acid).

CARBOXLIC ACIDS…are very important industrially…

… used in the production of polymers, pharmaceutical solvents and food preservatives

CARBOXLIC ACIDS…its production

causes air pollution

CARBOXLIC ACIDS… can cause skin and

eye irritation

CARBOXLIC ACIDSalso causes…

Pulmonary edema and Breast Cancer

CARBOXLIC ACIDS… is also

persistent organic pollutants

Abraham was born with no arms or legs after he waspoisoned by harmful pesticides sprayed on thefields where his mother was picking tomatoes.

No one can deny that

Carboxylic Acids have indeed done good but it is up to us to safeguard

and set limits for better.

Drugs containingCarboxylic acid

EXAMPLES FOR CARBOXYLIC ACIDS INCLUDED IN SOME DRUG :

• 1. Salicylic acid.

• 2.Fusidic acid.

• 3. Citric acid.

• 4. Ascorbic acid.

• 5. Benzoic acid.

• 6.Lactic acid.

• 7.Tartaric acid.