A convenient method for the synthesis of 2-arylazocarboxylates from 2-arylhydrazinecarboxylates by aerobicoxidation with ironphthalocyanine is described. The reaction is applicable to oxidative activation of 1-acyl-2-phenylhydrazines. Some preliminary experiments suggest Michaelis–Menten kinetics and participation of radical species in the reaction mechanism.
Synthesis of 2-Imino-1,3,4-thiadiazoles from Hydrazides and Isothiocyanates via Sequential Oxidation and P(NMe<sub>2</sub>)<sub>3</sub>-Mediated Annulation Reactions
N-acyldiazenes with isothiocyanates, producing 2-imino-1,3,4-thiadiazoles, is reported. This reaction proceeds well with crude N-acyldiazenes derived from the oxidation of hydrazides by iodine and permits the sequential synthesis of products directly from hydrazides without purification of the less stable N-acyldiazene intermediates. The reaction does not require transition metals and is a simple, scalable operation