Wolff Kishner Reduction

Wolff-Kishner Reduction:

This reaction is discovered by Ludwig Wolff and Nikolai Kischner in 1912.

It is an organic reaction in which an aldehyde or ketone reduces to an alkane in the presence of hydrazine, base, and thermal condition.

Example:

Mechanism of the reaction:

In general, the mechanism of the reaction involves following steps.

• In the starting, a hydrazone is formed by the condensation of hydrazine with the ketone or aldehyde substrate.

•  The obtained hydazone is deprotonated by alkoxide base.

• Proton transfer steps then result in the formation of a N=N bond.

• Deprotonation of   nitrogen and a rearrangement reaction result in the formation of carbanion and the release of nitrogen gas.

•  The carbanion then picks up a proton from water to regenerate the base catalyst and provides the final alkane product.