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.