The Activation of Bivalent Sulfur Compounds with Cupric Chloride and Zinc Chloride. The Benzylation and Acylation of Aromatic Compounds with Sulfides and Thiol Esters

Benzylation of aromatic compounds, such as anisole, m-xylene, toluene, and benzene, with various benzyl sulfides in the presence of equimolar amounts of cupric chloride and zinc chloride was investigated. For example, in the case of benzylation of anisole with 4-benzylthiopyridine, o- and p-benzylanisoles were obtained in 79% yield in the presence of cupric chloride and zinc chloride. On the other hand, when the reaction was carried out in the presence of cupric chloride alone, the yield of benzylanisoles was low. The similar activation with cupric chloride and zinc chloride was successfully applied to the reaction of aromatic compounds with benzaldehyde diethylthioacetal and to the acylation of aromatic compounds with 1,2-bis(acylthio)ethanes.