1,1-Di-tert-butyldiazene

1,1-Diazenes (aminonitrenes, N-nitrenes) are unstable species usually not isolated or directly observed. The recent syntheses of kinetically persistent 1, 1-diazenes, N-(2,2,6,6-tetramethylpiperidyl)nitrene and N-(2,2,5,5-tetramethylpyrrolidyl)nitrene, have allowed direct studies on this species. These five- and six-membered cyclic 1, 1-diazenes are equipped with a steric blockade to dimerization and are sufficiently long lived in solution at - 78 °C to permit spectroscopic inspection and purification by low temperature chromatography (-88 °C) for thermal and photochemical studies.4 Acyclic 1,1-diazenes have so far eluded detection. We report here the synthesis and direct observation of 1, 1-di-tert-butyldiazene ( 1 ), an isomer of the characterized azo compounds cis- and trans-1,2-di-tert-butyldiazenes (2 and 3)