Coupling of diazonium salts with acetone

Abstract

Diazonium salts or isodiazoates reacted with acetone in acid media to give the corresponding α-oxopropanal arylhydrazone in high yield. The kinetics of formation of α-oxopropanal p-nitrophenylhydrazone from sodium p-nitrobenzeneisodiazoate and acetone in presence of acids were studied in acetone solution at 25°. For a series of six acids of different acid strengths, pseudo-first-order rate constants were obtained, and the reaction was found to be of the second order, first order in the diazoate, and first order in acid. The mechanistic scheme proposed for hydrazone formation is supported by the present investigation.