Reaction of dimethyl phosphite and monomethyl phenylphosphonite with 2-methyl-3,4,5-triphenylcyclopentadienone

Abstract

In the absence of catalysts, the reaction of dimethyl phosphite and monomethyl phenylphosphonite with 2-methyl-3,4,5-triphenylcyelopentadienone goes with the formation of unconjugated β-phosphonoketones, which under the reaction conditions undergo prototropic isomerization to the conjugated β-phosphonoketones. In contrast to alcohols, dimethyl phosphite and monomethyl phenylphosphonite when reacted with the tricyclone do not form the products of 1,4-addition to the conjugated C=C-C=O system of the cyclone. © 1980 Plenum Publishing Corporation.