Tertiary Phosphane/Tetrachloromethane, a Versatile Reagent for Chlorination, Dehydration, and PN Linkage

Abstract

In this review the processes occurring on the treatment of triphenylphosphane with tetrachloromethane are first reported; a key role is played here by (trichloromethyl)phosphonium chloride which reacts with a further amount of the phosphane to give the stable salt [chloro(triphenylphos‐phoranediyl)methyl]triphenylphosphonium chloride by way of dichlorophosphorane and (dichloromethylene)phosphorane that is detectable only as an intermediate. The preparative application of the two‐component system as a chlorinating, dehydrating, and P—N‐linking reagent is ascribable to “phosphorylation” of the substrate in question through several reactive species. In these applications the reactions with the substrate compete with reactions of the two‐component system with itself, so that the overall course of the reaction is in nearly all cases much more complex than was previously assumed. Nevertheless. very good results can be achieved by the use of this reagent, high yields and mild reaction conditions being characteristic. Copyright © 1975 by Verlag Chemie, GmbH, Germany