Tetracycline studies. Part 5. New syntheses of anthracenes and anthraquinones through benzophenone carbanions

Abstract

The synthesis of anthracenes and anthraquinones by a novel method involving the cyclisation of carbanions derived from substituted benzophenones is described. The procedure gives good yields and is of wide applicability. Regiospecificity has been achieved by preferential displacement of chloride ion. In certain circumstances treatment of 2-cyanomethylbenzophenones with trifluoroacetic anhydride gives derivatives of isoquinolin-3-one.