SYNTHESIS OF CONJUGATED F-POLYENES CONTAINING THIENYL RING SYSTEMS

Novel 1-substituted F-1,3-butadienes ThioAr−CFCFCFCF2, ThioAr = 2-thienyl and 2-benzo[b]thienyl, and symmetrically 1,4-disubstituted F-1,3-butadienes ThioAr-CFCFCFCF−ThioAr, ThioAr = 5-R‘-2-thienyl (R‘ = Me, SiMe3, CFCFCl), 3-thienyl, and 4-dibenzo[b,d]thienyl, inclusive of the above-named substituents, were prepared by the reaction of organolithium derivatives with F-1,3-butadiene (PFBD). Monothioaryl-substituted F-1,3-butadienes were used as intermediates in subsequent reactions with other (thioaryl)organolithium derivatives for the synthesis of a new series of unsymmetrically substituted α,ω-bis(thioaryl)-F-polyenes ThioAr−(CFCF)n−ThioAr‘, where n = 2, ThioAr, ThioAr‘ = 4-RC6H4 (R = H, Me, OC6H11, NMe2), 2-thienyl, 5-methyl-2-thienyl, 2-benzo[b]thienyl, 4-dibenzo[b,d]thienyl, and for n = 3, ThioAr = 2-thienyl, ThioAr‘ = 5-methyl-2-thienyl. The reaction of 2,5-dilithiothiophene with 1-(2-thienyl)-F-1,3-butadiene affords 2,5-bis[4-(2-thienyl)-1,2,3,4-tetrafluoro-1,3-butadienyl]thiophene (5). 2,5-Thienyle...