TIPS-TTF as a precursor of low-symmetry TTF derivatives: steric protection strategy in the regioselective C-H modification of TTF.

Triisopropylsilyltetrathiafulvalene (TIPS-TTF) has been devised as a promising platform for the synthesis of low-symmetry TTF derivatives. The bulky TIPS group allows TIPS-TTF to undergo palladium-catalyzed direct diarylation as well as LDA-mediated dilithiation exclusively on the roomier dithiole ring. Subsequent fluoride-mediated protodesilylation provided vicinally difunctionalized TTF, which could undergo further functionalization.