Bis- and tetrakis-(diphenylphosphino)tetrathiafulvalenes as precursors of redox-active organic-inorganic polymeric networks

Lithiation of the (Z)-, (E)-dimethyltetrathiafulvalene mixture and subsequent reaction with ClPPh2 afford (Z)- and (E)-dimethyl-bis(diphenylphosphino)tetrathiafulvalene which are separated by fractional recrystallization. The identity of(Z)-P-2 has been ascertained by its X-ray crystal structure determination. By similar methods, tetrakis(diphenylphosphino)tetrathiafulvalene (P-4) is obtained from the tetrathiafulvalene tetralithium derivative. Cyclic voltammetry experiments reveal that the new compounds oxidize reversibly in two one-electron steps to the radical cation and dication. Reaction of o-P-2 with the dinuclear complex [Rh-2(NCCH3)(10)](BF4)(4) has been investigated and found to produce the square-planar Rh(I) compound [(o-P-2)(2)Rh][BF4]. The identity of the product has been confirmed by X-ray crystallography, FAB-MS, elemental analysis, and NMR spectroscopy. Several reactions of solvated cations were also performed, all of which appear to lead to products with o-P-2 and P-4 ligands.