Oxidative cleavage of the C-C bond in processes involving the heteroaromatization of 9R-sym-nonahydro-10-oxa(chalcogena)anthracenes

The reaction of 9-(2-methoxyphenyl)- and 9-(2-thienyl)-sym-nonahydro-10-selena(thia)anthracenes with trifluoroacetic acid causes their heteroaromatization with the elimination of substituents from the positions of the heterorings. A similar transformation of these compounds, as well as their oxygen and 9-benzyl-substituted analogs, occurs during anode electrochemical oxidation. The stepwise character of the cleavage of the C-C bond, which includes one-electron oxidation of the chalogenapyrans and subsequent fragmentation of the cation-radical intermediates, is substantiated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 900–904, July, 1991.