Hydrazine derivatives. Part II. Oxidation of aldehyde NN-disubstituted hydrazones with lead tetra-acetate

Abstract

The oxidation of a number of arenecarbaldehyde NN-disubstituted hydrazones with lead tetra-acetate proceeds in two steps. The first involves carbon–nitrogen bond cleavage to give an aldehyde and an arenecarbaldehyde monohydrazone. The second involves further oxidation of the monohydrazone to a diacylhydrazine. The order of ease of cleavage of alkyl groups was found to be p-methoxybenzyl > benzyl > p-chlorobenzyl methyl. A mechanism has been suggested for the cleavage reaction. The oxidation of the monohydrazone proceeds via a nitrilimine.