Selectivity in the electrophilic addition of carbenes and nitrenes to aliphatic sulphides and to 4-t-butylthian

Abstract

Photogenerated bisalkoxycarbonyl- and diacetyl-carbenes add exclusively equatorially to 4-t-butylthian and exhibit selectivity in competitive additions to mixtures of dimethyl and di-isopropyl sulphides. By contrast ethoxycarbonyl- and p-tolysulphonyl-nitrene give equal proportions of axial and equatorial adducts with the thian, and show no selectivity in competitive reactions with dialkyl sulphides. The results in most or all cases appear to be determined by kinetic control.