Question

Trans esterification is the process of

• A. conversion of an aliphatic acid to ester
• B. conversion of an aromatic acid to ester
• C. conversion of one ester to another ester
• D. conversion of an ester into its components namely acid and alcohol

Answer 1

The Correct Option is C

The process of transesterification involves the conversion of one ester to another ester. This is achieved through the exchange of the alkoxy group of an ester with the alkoxy group of an alcohol. Transesterification is an essential reaction in industrial applications, most notably in the production of biodiesel.

Let us break down the given options to justify the correct answer:

1. Conversion of an aliphatic acid to ester: This process is known as esterification, where an alcohol reacts with an aliphatic acid in the presence of an acid catalyst to form an ester and water. This is not transesterification.
2. Conversion of an aromatic acid to ester: Similar to the first option, this involves esterification but with aromatic acids instead of aliphatic ones. Again, this is not the process of transesterification.
3. Conversion of one ester to another ester: This is the correct description of transesterification. In this chemical reaction, the alkoxy group of an ester is exchanged with that of alcohol, resulting in the formation of a new ester. The reaction can be represented as: RCOOR' + R''OH \rightarrow RCOOR'' + R'OH where R, R', and R'' are alkyl or aryl groups.
4. Conversion of an ester into its components, namely acid and alcohol: This process is known as hydrolysis of esters, which occurs in the presence of water and an acid or base, and it is not transesterification.

Thus, the correct answer is: conversion of one ester to another ester.