Anodic acetamidosulphenylation and trifluoroacetoxysulphenylation of steroidal alkenes

Abstract

Electrochemical acetamidosulphenylation of a number of steroidal alkenes is described via oxidation of diphenyl, di-p-tolyl, dibenzyl and dipropyl disulphide in acetonitrile. The regiochemistry and stereochemistry of addition are established by analysis of the products to obtain n.m.r. coupling constant data, and by relation of the products to known steroidal amides via reductive desulphurisation. The addition of the same disulphides to steroidal alkenes promoted by lead(IV), manganese(III), and copper(II) salts in trifluoroacetic acid gave trifluoroacetoxy sulphides. Reaction of these esters with acetonitrile gave acetamido sulphides. Mechanisms and the relative merits of the direct and indirect methods of acetamidosulphenylation are discussed.