title: Monometallic Ni(0) and Heterobimetallic Ni(0) /Au(I) Complexes of Tripodal Phosphine Ligands: Characterization in Solution and in the Solid State and Catalysis.
abstract: The tridentate chelate nickel complexes [(CO)Ni{(PPh2 CH2 )3 CMe}] (2), [(CO)Ni{(PPh2 CH2 CH2 )3 SiMe}] (6), and [Ph3 PNi{(PPh2 CH2 CH2 )3 SiMe}] (7), as well as the bidentate complex [(CO)2 Ni{(PPh2 CH2 )2 CMeCH2 PPh2 }] (3) and the heterobimetallic complex [(CO)2 Ni{(PPh2 CH2 )2 CMeCH2 Ph2 PAuCl}] (4), have been synthesized and fully characterized in solution. All (1) H and (13) C NMR signal assignments are based on 2D-NMR methods. Single crystal X-ray structures have been obtained for all complexes. Their (31) P CP/MAS (cross polarization with magic angle spinning) NMR spectra have been recorded and the isotropic lines identified. The signals were assigned with the help of their chemical shift anisotropy (CSA) data. All complexes have been tested regarding their catalytic activity for the cyclotrimerization of phenylacetylene. Whereas complexes 2-4 display low catalytic activity, complex 7 leads to quantitative conversion of the substrate within four hours and is highly selective throughout the catalytic reaction.
authors.affiliation: Department of Chemistry, Texas A & M University, College Station, TX, 77842-3012 (USA).
authors.forename: Kyle J
authors.initials: KJ
authors.lastname: Cluff
authors.affiliation: Department of Chemistry, Texas A & M University, College Station, TX, 77842-3012 (USA).
authors.forename: Nattamai
authors.initials: N
authors.lastname: Bhuvanesh
authors.affiliation: Department of Chemistry, Texas A & M University, College Station, TX, 77842-3012 (USA). bluemel@tamu.edu.
authors.forename: Janet
authors.initials: J
authors.lastname: Blümel
keywords: NMR spectroscopy; homogeneous catalysis; nickel; phosphane ligands; solid-state structures