Stereocontrolled Preparation of Stereocomplementary Regioisomeric Tricarbonyliron Complexes in Enantiopure Form

Abstract

The use of ultrasound to form ferralactone complexes from an enantiomerically pure allylic epoxide with an adjacent hydroxymethyl substituent affords a pair of stereocomplementary isomers that offer a regioconvergent route to the same chiral pentadienyliron complex. The enantiomeric purity, CD properties, and absolute configurations of intermediate η 4-diene complexes are reported, and X-ray diffraction analysis of a pair of rearranged ferralactone complexes establishes their relative stereochemistries, and confirms their absolute stereochemistries.