Oxidation of tetrathiafulvalene (TTF) with Cu(BF4)2 in acetonitrile yielded (TTF)(BF4)2, a salt of the TTF dication. In acetonitrile, (TTF)CuCl4 was formed from CuCl2-2H20. In ethanol, (TTF)3(CuCl2)5 was obtained; it was converted, by recrystallization from acetonitrile, to (TTF)2CuCl4. From CuBr2 and TTF in acetonitrile, (TTF)CuBr3 was obtained, but in ethanol (TTF)3(CuBr2)5 was produced. Oxidation of TTF with HAuCi4-3H20 in acetonitrile or ethanol yielded (TTF)AuCl2 and (TTF)(AuCl4)2, respectively. These new metallotetrathiaethylenes were characterized by electronic, vibrational, EPR, and X-ray photoelectron spectroscopy and by measurement of the magnetic susceptibilities and electrical conductivity. Resonance Raman spectroscopy (RRS) proved especially valuable. The v3 mode, involving primarily stretching of the central C=C bond in TTF, shifts from 1512 cm-1 in TTF0 to 1416 and 1308 cm-1 in TTF+. and TTF2+, respectively. These large shifts are useful in assigning the oxidation state(s) of the TTF moiety in metallotetrathiaethylenes. For example, bands at 1418 and 1298 cm-1 in (TTF)3(CuCl2)5 indicate that is is a mixed-valence material formulated as (TTF+-)(TTF2+)2(CuCl2-)5.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry