Oxidation of ketone and aldehyde hydrazones, oximes, and semicarbazones and of hydroxylamines and hydrazo-compounds, using benzeneseleninic anhydride

Abstract
Benzeneseleninic anhydride (1; BSA) is an effective reagent for the mild regeneration of the carbonyl group from ketone phenyihydrazones, p-nitrophenyihydrazones, tosyihydrazones, oximes, and semicarbazones at 40–50 °C. Tosylhydrazones and oximes of aldehydes are also readily converted into the parent aldehyde. The phenylhydrazone and p-nitrophenylhydrazone derivatives of aldehydes afford ketoazo-compounds. The ketoazo-species could also be prepared by oxidation of the corresponding hydrazide with compound (1). Both aromatic and aliphatic hydrazo-compounds and hydroxylamines can be oxidised to azo- and nitroso-derivatives respectively.