Q53E - Organic Chemistry (Mcmurry)

Question

The Wharton reaction converts an epoxy ketone to an allylic alcohol by reaction with hydrazine. Propose a mechanism. (Hint: Review the Wolff–Kishner reaction in Section 19-9.)

Step-by-Step Solution

Answer

Step 1: Wharton reaction

Wharton reaction is the reaction that involves the reduction of $\alpha ,\beta$ unsaturated epoxy ketones into allylic alcohols.

We know that the Epoxidation of $\alpha ,\beta$  unsaturated ketones is done by hydrogen peroxide in a basic medium. In this reaction, further hydrazine is added to get the resultant product.

Step 2: Mechanism of the reaction

First, the nitrogen lone pair of hydrazine open the epoxide ring. Further rearrangements take place and nitrogen gas is lost as the reaction is proceed.

The mechanism of the reaction is as shown below;