Chapter 20, Problem 20.56P

Interpretation Introduction

Interpretation:

A stepwise mechanism for the given transformation is to be stated.

Concept introduction:

Grignard reagents react with derivatives of carboxylic esters $\text{RCOZ}$ (where, $\text{Z}=\text{Cl}\text{or}{\text{OR}}^{\text{'}}$) to yield ketones or ${\text{3}}^{}$° alcohols. The reaction utilizes two equivalents of Grignard reagent. However, when $\text{Z}={\text{OR}}^{\text{'}};\text{R}={\text{OR}}^{\text{'}}$, the reaction utilizes three equivalents of Grignard reagent to yield tertiary alcohol.