作者:Brittany J. Barrett、Vlad M. Iluc
DOI:10.1021/om500256r
日期:2014.5.27
The coordination chemistry of 2,2'-bis(di-iso-propylphosphino)trans-stilbene (tPCH=CHP) with group 10 metal centers in a variety of oxidation states is reported; different coordination modes were observed depending on the oxidation state of the metal. With metal centers in the 0 or +1 oxidation state ((tPCH=CHP)Ni, [(tPCH=CHP)Pd](2), (tPCH=CHP)NiCl, (tPCH=CHP)Nil), eta(2) coordination of the olefin occurs, whereas, with metals in the +2 oxidation state, C H activation of the backbone, followed by rapid H X reductive elimination, was observed, leading to an coordination of the backbone in (tPC=CHP)MCl (M = Ni, Pd, Pt). Employing the methyl-substituted analogue, 2,2'-bis(di-iso-propylphosphino)-trans-diphenyl-1,2-dimethylethene (tPCMe=CMeP), forced an eta(2) coordination of the olefin in [(tPCMe=CMeP)NiCl](2)[NiCl4]. The synthesis of the hydride complex (tPC=CHP)NiH was attempted, but, instead, led to the formation of (tPCH=CHP)Ni, indicating that the vinyl form of the backbone can function as a hydrogen acceptor. All metal complexes were characterized by multinuclei NMR spectroscopy, X-ray crystallography, and elemental analysis.