PREPARATION OF SOME ALKYL CHLORIDES BY DECOMPOSITION OF ALKOXYPHOSPHONIUM CHLORIDES AND BICHLORIDES

Abstract

A number of alkoxyphosphonium chlorides and bichlorides have been prepared as stable intermediates or transient species. The thermal decompositions of these salts have been studied under a variety of conditions. The salts decompose by S_N2 and S_N1 processes in a fairly predictable manner. There are two decided advantages to using these salts as precursors to alkyl halides. The first is that in systems that are normally prone to rearrangements under substitution conditions, the products of the decompositions of the salts are often formed with less rearrangement than is often found in other systems. The second is that the phosphates and phosphine oxides are excellent leaving groups and thus substitutions can be effected at centers that normally react very slowly.