10-Thia-anthracenes. Part 3. A re-examination of the reaction of 9-phenylthioxanthylium salt and phenyl-lithium

Abstract

Reaction of 9-phenylthioxanthylium salt (1) with phenyl-lithium afforded eight compounds, 9-phenyl(2), 9,9-diphenyl-(3), 3,9-diphenyl-(4), 3,9,9-triphenyl-(5), and 4,9,9-triphenyl-thioxanthene (6), 9,9′-diphenyl-9,9′-bithioxanthenyl (7), thioxanthone (8), and 9,9′-diphenyldithioxanth-9-yl peroxide (9). Their structures were determined by comparison with the authentic samples. Six samples, (3)–(6), 2,9,9-triphenyl-(30), 9-(biphenyl-4-yl)-9-phenylthioxanthene (31) were independently synthesized in order to determine the structures of two pairs of positional isomers, 3,4, and 5,6. A radical mechanism contributed to the reaction of compound (1) with phenyl-lithium.