Synthesis and X-ray crystal structure of the tungsten dimetallatetrahedrane complex[W 2 Cl 4 (µ-Cl) 2 (µ-C 2 Me 2 )(THF) 2 ](THF = tetrahydrofuran)

Treatment of {[W2Cl7(THF)5]Na} with excess of alkyne gives the dimetallatetrahedrane compounds, [W2Cl4(µ-Cl)2(µ-C2RR′)(THF)2](R = R′= H, Me, Et; R = H, R′= Ph); the X-ray crystal structure of [W2Cl4(µ-Cl)2(µ-C2Me2)(THF)2](1) reveals a confacial bioctahedral co-ordination environment about the ditungsten centre with a bridging alkyne unit.