MECHANISM OF DIMERIZATION OF 1,4-DITHIAFULVENES INTO TTF VINYLOGUES

Mechanism of the oxidative dimerization of DTF (dithiafulvenes) to for m TTF vinylogues (tetrathiafulvalenes) has been investigated by cyclic voltammetry at low and high scan rates for a series of substituted DT F. It involves first the formation of the cation radical which couples to form the protonated dication. This dication slowly deprotonates to give the final TTF (k=0.5-1 s(-1)). The dimerization rate constant wa s found to be in the range of k(dim)=(2-4) x 10(8) L mol(-1) s(-1) and not vary much with the nature of the substituent.