Frontier molecular orbital control of stereochemistry in organometallic electrocyclic reactions

Abstract

A qualitative molecular orbital picture is presented that allows the classification of certain transition metal promoted ring-openings as allowed or forbidden, and further shows that for allowed disrotatory ring-openings the rotational mode that bends the breaking σ bond towards the metal should be preferred whereas for forbidden disrotatory reactions bending of the σ bond away from the metal is the lower energy process.