SYNTHESIS OF THE ISOMERIC PHENOLS OF BENZ[A]ANTHRACENE FROM BENZ[A]ANTHRACENE

Novel and convenient syntheses of seven isomeric phenols of benz[a]anthracene (1-, 2-, 3-, 8-, 9-, 10-, and 11-HO-BA) from the parent polycyclic hydrocarbon are described. These syntheses demonstrate the feasibility of introduction of functional groups into polycyclic arene ring positions not prone to direct substitution through initial regioselective hydrogenation (or metal-ammonia reduction), followed by appropriate synthetic operations to introduce carbonyl or other desired functional groups into benzylic or olefinic ring positions and finally dehydrogenation. Fewer synthetic steps are generally required, and overall yields are superior to those obtained via the conventional synthetic approaches which entail total synthesis of each isomeric derivative from appropriately substituted smaller molecular units. Conversion of the aryl ketonic intermediates to phenols is accomplished by a new general method involving dehydrogenation of the corresponding enol acetate derivatives with ochloranil. © 1979, American Chemical Society. All rights reserved.