Preparation of lactones via tricarbonyliron–lactone complexes

Abstract

A number of tricarbonyliron–lactone complexes have been prepared from vinyl oxirans by treatment with pentacarbonyliron. In certain cases two η³-allyl complexes were isolated from a single vinyl oxiran. Oxidation of the complexes by cerium(IV) ammonium nitrate in acetonitrile leads predominantly to β-lactones. The stereochemical integrity of the initial complexes is reflected in the formation of the oxidation products. Reduction of these products with lithium aluminium hydride gave the expected diols.