Migration of the amino group in the base-induced rearrangements of N-(aminophosphinoyl)-O-sulphonylhydroxylamines

Abstract

The N-phosphinoylhydroxylamines R¹R²P(O)NHOH having R¹= R²= PhNH; R¹= Ph, R²= PhNH; and R¹= Ph, R²= Me₂N have been prepared and converted into their O-methylsulphonyl derivatives. The methanesulphonates rearrange in methanol containing sodium methoxide or pyridine, an amino group (PhNH or Me₂N) migrating from phosphorus to nitrogen. These reactions are much faster than the analogous reactions of Ph₂P(O)NHOMs involving migration of a Ph group, and with the unsymmetrical substrates migration of the amino group occurs to the complete exclusion of phenyl migration.