Direct Observation of an Imidoylnitrene: Photochemical Formation of PhC(=NMe)-N and Me-N from 1-Methyl-5-phenyltetrazole.

The imidoylnitrene 8, N-methyl-C-phenylimidoylnitrene, has been generated by laser photolysis of 1-methyl-5-phenyltetrazole 6 at 5 K and characterized by its ESR spectrum (|D/hc|=0.9602, |E/hc|=0.0144 cm-1 ). In addition, the triplet excited states of 6 and of 2-methyl-5-phenyltetrazole 11 were also observed by ESR spectroscopy in the 5 K matrices (6: |D/hc|=0.123 cm-1 , E/hc=0.0065 cm-1 , 11: |D/hc|=0.126 cm-1 , |E/hc|=0.0056 cm-1 ). The imidoylnitrene 8 is unstable both thermally (disappearing at 80 K) and photochemically (disappearing on continued irradiation at 266 nm). Methyl(phenyl)carbodiimide is the end product of photolysis.