The endocyclic restriction test: Determination of the transition-structure geometry for the transfer of oxygen from N,N-dialkylhydroxylamines to triarylphosphines

Article abstract of DOI:10.1021/ja00055a009

The transfers of oxygen from nitrogen to phosphorus in the conversions of 1 to 2 and 3 to 4 are shown by kinetic, solvent-labeling, and double-labeling criteria to be intramolecular reactions. This information in conjunction with the stabilities of 13 and 14 is taken to rule out the mechanisms of classic linear S_N2 substitutions at oxygen or nitrogen, biphilic insertion, or a radical chain reaction and to favor reactions via a 10-P-5 species (18). These results appear to provide the first experimental demonstration that oxygen can be transferred at an oblique angle.