Chapter 21.5, Problem 21.7P

(a)

Interpretation Introduction

Interpretation: The products resulting from the vigorous oxidation of the given compound by ${\text{H}}_{\text{2}}{\text{CrO}}_{\text{4}}$ have to be predicted.

Concept Introduction:

Oxidation with $H_{2}Cr{O}_4$at benzylic position:

The carbon atom attached to the benzene ring is known as benzylic carbon atom. The benzylic carbon that is attached with a benzylic hydrogen atom will be oxidized into carboxylic acid group on treatment with chromic acid $\left({\text{H}}_{\text{2}}{\text{CrO}}_{\text{4}}\right)$. In this process, the other groups attached to the benzylic carbon atom will be removed.

General scheme:

(b)

Interpretation Introduction

Interpretation: The products resulting from the vigorous oxidation of the given compound by ${\text{H}}_{\text{2}}{\text{CrO}}_{\text{4}}$ have to be predicted.

Concept Introduction:

Oxidation with $H_{2}Cr{O}_4$at benzylic position:

The carbon atom attached to the benzene ring is known as benzylic carbon atom. The benzylic carbon that is attached with a benzylic hydrogen atom will be oxidized into carboxylic acid group on treatment with chromic acid $\left({\text{H}}_{\text{2}}{\text{CrO}}_{\text{4}}\right)$. In this process, the other groups attached to the benzylic carbon atom will be removed as ${\text{CO}}_{\text{2}}$ .

General scheme:

In this oxidation, halogen and nitro substituents on the benzene ring are unaffected as shown in the following example:

Example: