Synthesis and photoreactivity of aryl substituted 4,5-dithienyl[1,3]dithiol-2-ones

Abstract UV irradiation of hitherto unknown 4,5-bis-benzo[ b ]thiophen-3-yl-[1,3]dithiol-2-one gave 3-(3-benzo[ b ]thienyl)-thieno[3,4-c]benzo[ e ][1,2]dithiine by loss of carbon monoxide and rearrangement, whereas 4,5-bis-(2-bromo-phenyl)-[1,3]dithiol-2-one gave a polymeric material containing S–S bridges. The structures of both photoproducts were demonstrated on the basis of chemical behaviour and/or X-ray diffraction.