Chapter 16, Problem 32P

Interpretation Introduction

Interpretation:

A three step sequence showing all necessary reagents for the preparation of m-methoxybenzyl cyanide from m-methoxybenzaldehyde is to be suggested.

Concept Introduction:

Aldehydes upon reduction with a reducing agent like ${\text{NaBH}}_{\text{4}}$ get converted to alcohols.

The hydroxyl group is not a good leaving group. Reaction of alcohols with tosyl chloride converts the hydroxyl group to a good leaving group.

The reaction of $\text{NaCN}$ with a tosyl group results in a substitution reaction. The tosyl group is the leaving group and the cyanide group is the nucleophile. The reaction mechanism for this reaction is ${\text{S}}_{\text{N}}\text{2}$.