Synthesis and structure of the dinuclear tungsten(v) complex {HB(Me2C3N2H)(3)}WS(mu-S)(2)WS(S2PPh2)

The complex (LWS)-S-V(mu-S)(2)(WS)-S-V(S2PPh2) [L = tris(3,5-dimethylpyrazo l-1-yl)hydroborate] results from the reaction of (LWO2Cl)-O-VI with PPh3 in refluxing pyridine, followed by the addition of NH4S2PPh2 and reflux for a further 4 days. Crystals of LWS(mu-S)(2)WS(S2PPh2). 0.5CH(2)Cl(2) are mono clinic and belong to space group Cc with a 12.356(2), b 30.067(6), c 22.082 (4) Angstrom, beta 96.08(2)degrees and Z 8. Refinement of 10507 data measur ed with Mo K alpha radiation converged at R 0.0466 and R-w 0.1421. The two independent molecules in the unit cell are dinuclear with a syn-[W2S2(mu-S) (2)](2+) core. One tungsten centre is further coordinated by a tridentate L ligand, making it six-coordinate with a distorted octahedral geometry whil e the other bears a bidentate dithiophosphinate ligand and is five-coordina te and square-pyramidal in geometry. The terminal thio-tungsten distances a verage 2.120 Angstrom, and the parameters of the core [W-W av. 2.832 Angstr om, W-(mu-S) av. 2.311 Angstrom, S-W-S av. 100.2 degrees, W-S-W av. 75.2 de grees] are typical of syn-[W2S2(mu-S)(2)](2+) complexes.