106151-45-5Relevant academic research and scientific papers
Preparation and spectral properties of a series of bis(phosphite) alkyne complexes and x-ray crystal structure of [WI2(CO){P(OMe)3}2(η2-MeC 2Me)]
Baker, Paul K.,Armstrong, Elaine M.,Drew, Michael G. B.
, p. 2406 - 2410 (2008/10/08)
The complexes [WI2(CO)(NCMe)(η2-RC2R)2] (R = Me, Ph) react with 2 equiv of P(OR′)3 (R′ = Me, Et, iPr, nBu) in CH2Cl2 at room temperature to give the four-electron alkyne compounds [WI2(CO){P(OR′)3}2(η 2-RC2R)] (1-8) via displacement of acetonitrile and an alkyne ligand, respectively. X-ray single-crystal crystallographic studies were carried out on the complex [WI2(CO){P(OMe)3}2(η2-MeC 2Me)] (1). Crystals of 1 are orthorhombic, space group Pnab, in a unit cell of dimensions a = 14.214 (12), b = 15.332 (12), and c = 20.350 (25) A?. The structure was refined to R = 0.062 for 2164 reflections with I > 3σ(I). The coordination geometry around tungsten in 1 may be considered in terms of a pseudooctahedral structure. The complex has cis-iodide ligands, which are trans to a P(OMe)3 and a but-2-yne ligand. The other two sites are occupied by carbonyl and P(OMe)3 ligands. 31P NMR studies are interpreted in order to suggest the geometry of complexes 1-8 in solution. The barrier to but-2-yne rotation of 1 is 55.3 kJ mol-1. 13C NMR chemical shifts of the alkyne contact carbons above 200 ppm in these complexes indicate that the alkyne ligand is acting as a four-electron donor in these compounds.
