Oxidative cleavage of the CN bond during singlet oxygenations of amidoximates

Amidoximes are inert toward singlet oxygen (1O2), however, the photooxygenation of amidoximate anions proceeds smoothly and in high yield to give mixtures of amides and nitriles. The mechanism of these reactions appears to involve carbonyl oxide intermediates. The oxidative cleavage of amidoximates closely resembles the results obtained from nitric oxide synthase (NOS) oxidations of N-hydroxyarginine.