Oxidation of bis-sulfinyl carbanions as the pivot of ionic/radical tandem reactions

[1,4]-additions of various nucleophiles such as lithiated carbamates, alkoxides or ester enolates onto enantiopure alkylidene bis-sulfoxides proceed with high diastereoselectivity. The oxidation of the resulting carbanions with iron(III) salts induces the radical cyclizations onto alkenes with a high diastereoselectivity leading to enantiopure carbo- or heterocycles. Moreover, allylic radicals have been generated by deprotonation or [1,6]-conjugate addition from alkylidene bis-sulfoxides followed by oxidation.