Preparations of Acid Derivatives Acid chlorides From carboxy

Preparations of Acid Derivatives Acid chlorides From carboxylic acids with Acid anhydrides From acid chlorides with From condensation of two carboxylic acid (or diacids) Esters and ROHs From From acid anhydrides and ROHs From Transesterification with another ROHs and with acid catalyst (Fischer) Amides From acid chlorides and .From acid anhydrides and From acid, not directly via coupling reagents such as DCC (Dicyclohexylcarboimide) Mechanism of DCC Coupling (optional) From acid chloride and cyanide Nitriles SN2 with cyanide Addition of HCN to aldehydes/ketones

Solution

Carboxylic acids on treatment with thionyl chloride or phosphorous pentachloride or any such strong chlorinating agents result in the replacement of the hydroxyl group of hte acids with chloride thus giving acyl chlorides.

Acyl chlorides on treatment with carboxylic acids condense into acid anhydrides expelling hydrogen chloride and producing acid anhydrides.

Esters are the products of condensation of alcohols and carboxylic acids. Thus reactive acidic species like acyl chlorides and acid anhydrides or even carboxylic acid, activated by catalysts, on treatment with alcohols produce esters. Thus esters can be made from acyl chlorides and ROHs and from carboxylic acids and alcohols with acid catalyst.

Amides, like esters are amine counterparts of esters where instead of alcohols, amines are used. Thus, similar to esters, acid chlorides and amines/ammonia or acid anhydrides and amines/ammonia result in condensation to form amides.