Serendipitous Synthesis of (tert-Butyl-NNO-azoxy) acetonitrile: Reduction of an Oxime Moiety to a Methylene Unit

(tert-Butyl-NNO-azoxy) acetonitrile (1) is a useful precursor for a number of nitrogen heterocycles. It was found that it could be obtained in good yield by treatment of the salts of (tert-butyl-NNO-azoxy)(hydroxyimino) acetonitrile with NH2OTs. It is the first case of one-step reduction of an oxime group to a methylene unit using an aminating agent. A plausible reaction mechanism is proposed. In addition, a new strategy for the tetrazole 1-oxide ring construction was developed. This involves a diazo-group transfer to the active-methylene unit of compound 1, followed by intramolecular coupling of the azoxy and diazo groups. The tetrazole structures were confirmed by X-ray diffraction analysis.