Tetrathiafulvalene-functionalized phosphine as a coordinating ligand.: X-Ray structures of (PPh2)4 TTF and [(AuCl)4{(PPh2)4TTF}]

The phosphine (PPh2)(4) TTF (P4) (1) reacts with the gold() complexes [AuX( tht)] (X = Cl, C6F5; tht = tetrahydrothiophene) or [Au(Mes)(AsPh3)] (Mes = 2,4,6-Me3C6H2) to give tetranuclear derivatives [( AuX)(4)P4] (X = Cl, 2; C6F5, 3; Mes, 4). The analogous reaction starting with [Au(Trip)(AsPh3)] (Trip = 2,4,6-Pr-i(3) C6H2) provides the dinuclear derivative [(AuTrip)(2) P4] (5). When the phosphine P4 reacts with [Cu( MeCN)(4)]PF6, AgCF3SO3 or [Au(tht)(2)]CF3SO3 in a 2: 1 molar ratio, complexes [M(P4)(2)]A (A = PF6, M = Cu, 6; A = CF3SO3, M = Ag, 7, Au, 8) are obtained, or {[M2P4]( CF3SO3)(2)}(n) (M = Ag, 9; Au, 10) when 1: 1 molar ratios are used instead. Visible- ultraviolet and electrochemical studies of the new complexes are reported. Two, reversible one-electron oxidations to the mono- and di-cation occur in complexes 2-10 at more positive potentials than the two reversible oxidations exhibited by the free P4 (1) ligand. The structures of 1 and 2 have been confirmed by X-ray analysis.