Answer to Question #163861 in Organic Chemistry for Anand

Question

Taking suitable example write the mechanism of benzoin condensation.

Answer 1

Benzoin Condensation : The benzoin condensation is the condensation between two molecules of benzaldehyde to form benzoin in the presence of a cyanide catalyst (e.g., NaCN and KCN)

Mechanism : The standard method for performing the benzoin condensation begins with benzaldehyde treated with a catalytic amount of sodium cyanide in the presence of a base. The cyanide ion forms a stable cyanohydrin intermediate. This step is followed by a condensation reaction in which the cyanohydrin reacts with a second mole of benzaldehyde. The final product is benzoin.

It is done by 3 steps,

(Step by step procedure is explained in the following figure)