Photolysis of N-phenylhydroxylamine: a novel photochemical disproportionation reaction in N-O bond cleavage assisted by hydrogen bonding

The photochemistry of N-phenylhydroxylamine (9) has been examined in the so lution phase and in the solid state. The major products are aniline and nit rosobenzene. The nitrosobenzene quickly reacts with 9 to generate azoxybenz ene and with aniline to produce azobenzene. The quantum yields for the disa ppearance of 9 are reasonably high (0.25-0.29) and suggest that the photoch emical reactions proceed from a hydrogen-bonded dimer. (C) 1999 Elsevier Sc ience S.A. All rights reserved.