Poly(4,5,6,7-tetrafluorobenzo[c]thiophene) and related oligomers: a class of manipulable conjugated materials. Part 1.—Syntheses

Abstract
Dehydrogenation of the precursor polymer, poly(1,3-dihydro-4,5,6,7-tetrafluorobenzo[c]thiophene)5 with DDQ has provided a convenient chemical synthesis of poly(4,5,6,7-tetrafluorobenzo[c]thiophene)7, a stable material which is soluble in chlorinated solvents. Lithiation of 4,5,6,7-tetrafluorobenzo[c]thiophene 4, followed by oxidative coupling with copper(II) chloride, gave the conjugated oligomers 6n= 2–7. By analogous reactions, the dimer 6n= 2 was converted into the tetramer, hexamer and octamer 6, n= 4,6,8, respectively, and the trimer gave the hexamer and nonamer 6, n= 6,9, respectively.