Synthesis and Structure of the Dinuclear Tungsten(V) Complex {HB(Me2C3N2H)3}WS(µ-S)2WS(S2PPh2)

Abstract

The complex LW ^V S(µ-S) ₂ W ^V S(S ₂ PPh ₂ ) [L = tris(3,5-dimethylpyrazol-1-yl)hydroborate] results from the reaction of LW ^VI O ₂ Cl with PPh 3 in refluxing pyridine, followed by the addition of NH ₄ S ₂ PPh ₂ and reflux for a further 4 days. Crystals of LWS(µ-S) ₂ WS(S ₂ PPh ₂ )·0.5CH ₂ Cl ₂ are monoclinic and belong to space group Cc with a 12.356(2), b 30.067(6), c 22.082(4) Å, β 96.08(2)° and Z 8. Refinement of 10507 data measured with Mo Kα radiation converged at R 0.0466 and R _w 0.1421. The two independent molecules in the unit cell are dinuclear with a syn-[W ₂ S ₂ (µ-S) ₂ ] ²⁺ core. One tungsten centre is further coordinated by a tridentate L ligand, making it six-coordinate with a distorted octahedral geometry while the other bears a bidentate dithiophosphinate ligand and is five-coordinate and square- pyramidal in geometry. The terminal thio–tungsten distances average 2.120 Å, and the parameters of the core [W–W av. 2.832 Å, W–(µ-S) av. 2.311 Å, S–W–S av. 100.2°, W–S–W av. 75.2°] are typical of syn-[W ₂ S ₂ (µ-S) ₂ ] ²⁺ complexes.