Control over cyclisation pathways in the reaction of chlorosulphonyl isocyanate with olefins

Abstract

A β-lactam derivative has been interceptted in the reaction of CSI with camphene at –60° and at higher temperatures the products are shown to be derived via heterolysis, rearrangement and cyclisation through nitrogen or oxygen in the ambident anion with no proton transfer; the behaviour of α-fenchene under identical conditions is compared and contrasted and solvent control over secondary cyclisations is described.