Question

How would you find all the isomers of the formula\[{{C}_{4}}{{H}_{8}}{{O}_{2}}\](ester)?

Answer 1

Hint: Ester is a chemical compound which is derived from an acid in which the last alcoholic group is replaced by an alkyl group also known as the alkoxy group. Generally esters are derived from substitution reactions of carboxylic acid and alcohols.

Complete step by step answer:
The word isomer is derived from two Greek words called iso + mer where iso means equal and mer means parts i.e. equal parts. Isomers are defined as those compounds which have the same chemical formula but different arrangement of molecules and the phenomenon of isomers is known as isomerism.
Isomers are generally of two types: Structural isomerism and Geometrical isomerism. Structural isomers are also known by the name constitutional isomerism in this type of isomerism the functional group and the atoms in the molecules of these isomers are linked in different ways. Whereas in geometrical isomerism compounds have the same chemical formula but different orientations of the atoms in three dimensional space.
Isomerism in the given example is known as metamerism which arises due to the presence of different alkyl chains on each side of the functional group. the isomers possible in this case are shown as:
1. $HCOOC{{H}_{2}}C{{H}_{2}}C{{H}_{3}}$- Propyl formate
2. $HCOOCH{{(C{{H}_{3}})}_{2}}$- Isopropyl formate
3. $C{{H}_{3}}COOC{{H}_{2}}C{{H}_{3}}$- Ethyl acetate
4. $C{{H}_{3}}C{{H}_{2}}COOC{{H}_{3}}$- Methyl propionate
Hence there are four isomers present for the formula \[{{C}_{4}}{{H}_{8}}{{O}_{2}}\].

Note: Metamerism is kept in the category of structural isomerism and it is a special type of isomerism as this type of isomerism is possible only in those compounds which contain a divalent atom like sulfur or oxygen surrounded by alkyl groups.