39049-86-0Relevant academic research and scientific papers
Reactions of WCl2L4 (L = a phosphine). 1. A new class of tungsten(II) ethylene complexes
Sharp, Paul R.
, p. 1217 - 1223 (2008/10/08)
WCl2L4 can be prepared by reducing WCl4Ln with 2 equiv of sodium amalgam in the presence of L (L = PMe3, n = 3; L = PMe2Ph and PMePh2, n = 2). Phosphine is displaced from WCl2L4 by ethylene to give first WCl2L3(C2H4) (L = PMe3) and then WCl2L2(C2H4)2. WCl2(PMe3)2(C2H4) 2 reacts with TlBF4, AlCl3, and AlMe3 to give cationic complexes. The X-ray crystal structure of one of these, [WMe-(PMe3)2(C2H4) 2][ClAlMexCl3-x], was determined. The crystals are monoclinic (P21/n) with a = 9.922 (2) ?, b = 7.419 (1) ?, c = 29.241 (4) ?, β = 92.79 (2)°, V = 2150 ?3, and Z = 4. The three-dimensional X-ray data were measured with the θ-2θ scan technique with a scintillation detector. The structure was resolved by Patterson and Fourier methods and refined by full-matrix least-squares calculations to give R(Fo) = 0.025 and Rw(Fo) = 0.032 for 1362 observations above 2σ. The solid state structure consists of monomeric units with cis ethylenes, trans phosphines, and a weakly coordinated aluminate. NMR and conductivity data suggest the equilibrium in solution of this structure with an ionic complex formed by loss of the aluminate. The reaction of this complex with tmeda (N,N,N′,N′ -tetramethylethylenediamine) or other Lewis bases gives neutral WMeCl(PMe3)2(C2H4)2 that loses Cl- in polar, noncoordinating solvents.
