Synthesis of Tosylhydrazines by the Reduction of Tosylhydrazones with Pyridine-Borane

Abstract

Reduction of tosylhydrazones is very important in synthetic chemistry for the conversion of carbonyl derivatives to methyl or methylene group. Although metal hydrides reduction of tosylhydrazones^1,2 offers a mild and convenient alternative method to the Wolff-Kishner and Clemmensen reductions, tosylhydrazones of aryl carbonyl derivatives are resistant to hydride reduction. According to the recent report, ³ this limitation was overcome by the mild reduction of N,N'-mercurio-bis-tosylhydrazones.