Chapter 18, Problem 18.90P

Interpretation Introduction

Interpretation:

The complete and detailed mechanism for the given example of Darzen’s reaction is to be drawn.

Concept introduction:

In this chemical reaction, carbonyl compound (ketone & aldehyde) reacts with $\text{**\#x03B1;}$-haloester in the presence of a strong base to form an alpha epoxy ester. At the halogenated position a carbanion is formed by strong base. Then the nucleophile attacks the carbonyl carbon to form a carbon-carbon bond. Then, through the intermolecular ${\text{S}}_{\text{N}}\text{2}$ attack, the halide is discplaced to form an epoxide.