Alkylation of Phospha-ylid Complexes. Application to the Synthesis of 1-Chlorophosphirane

Abstract

[Phenyl(tributylphosphoranylidene)phosphine]pentacarbonyltungsten, W(CO)₅(Bu₃P=PPh), reacts with iodomethane and methanol to give [phenyl(methyl)(methoxy)phosphine]-pentacarbonyltungsten via initial alkylation of the complexed phosphorus atom and cleavage of the P-P bond. Self-alkylation spontaneously takes place in 4-chlorobutyl- and 2-chloroethyl(tributylphosphoranylidene)phosphine-tungsten complexes, leading to (1-chlorophospholane)pentacarbonyltungsten and to free 1-chlorophosphirane, respectively.