Question

An aromatic compound 'X' with molecular formula C₉H₁₀O
gives the following chemical tests. It
(i) forms 2, 4-DNP derivative
(ii) reduces Tollen's reagent
(iii) undergoes Cannizaro reaction and
(iv) on vigorous oxidation 1, 2-benzenedicarboxylic acid is
obtained.
X is

Answer 1

X is :

1. Forms 2,4-DNP derivative

=> 2,4-DNP test is used to detect the carbonyl group like ketone and aldehyde.

=> Ketone or aldehyde reacts with 2,4-DNP to give yellow, orange or red precipitate.

2. Reduces Tollen's reagent ( AgNO3 + NH4OH )

=> Tollen's reagent is used to detect aldehydic group

=> Aldehyde reacts with tollen's reagent to give deposition of silver mirror.

3. Undergoes Cannizaro reaction

=> Cannizzaro reaction is a redox reaction in which two same or different molecules of aldehydes react to produce primary alcohol and carboxylic acid.

• From these above three tests, It got confirmed that X have aldehydic group on it.

4. On vigorous oxidation 1, 2-benzenedicarboxylic acid is obtained.

=> X must have -CHO group directly attached to benzene ring and also compound should be ortho di-substituted Benzene

The compound X is : 2-ethylbenzaldehyde.