SYNTHESIS OF SYMMETRICALLY SUBSTITUTED BIS-TTF FUSED 1,4-DITHIINE (BTDT) DERIVATIVES

To prepare the title compounds which show bent molecular shapes at the centers, a general synthetic route is developed. The successive treat ment of 4,5-Vinylenedithio-1,3-dithiole-2-thione (5) with LDA, sulfur and thiophosgene gave the key intermediate of the dithione (6). The th iocarbonyl groups were oxidized to carbonyl groups by Hg(OAc)(2). The coupling reaction of this diketone(7) and 4,5-bis(methylthio)-1,3-dith iole-2-thione (10) gave (MeS)(4)BTDT (1, R-1 = R-2 = SCH3) as the firs t example utilizing our synthetic strategy.