Synthesis, structure, and electrical properties of naphthacene, pentacene, and hexacene sulphides

Abstract
Pentacene and hexacene both react with sulphur to form stable hexasulphides for which double fused thiathiophthen structures (6) and (8) or (9) are proposed. The electrical conductivity of hexacene hexasulphide is similar to that of the well-known naphthacene tetrasulphide (1) and 109 times greater than that of pentacene hexasulphide. Replacement of the sulphur in (1) by selenium gives a tetraselenide (14) of similar conductivity to (1). The new naphthaceno[5,6-cd][1,2]dithiole (10) is described.