1,1,1-Tris(diphenylphosphinomethyl)ethane explained
1,1,1-Tris(diphenylphosphinomethyl)ethane, also called Triphos, is an organophosphorus compound with the formula CH3C[CH<sub>2</sub>PPh<sub>2</sub>]3. An air-sensitive white solid, it is a tripodal ligand ("three-legged") of idealized C3v symmetry. It was originally prepared by the reaction of sodium diphenylphosphide and CH3C(CH2Cl)3:[1]
3 Ph2PNa + CH3C(CH2Cl)3 → CH3C[CH<sub>2</sub>PPh<sub>2</sub>]3 + 3 NaCl
It forms complexes with many transition metals, usually as a tripodal ligand.[2] Such complexes are used to analyze mechanistic aspects of homogeneous catalysts.[3] For example, rhodium forms complexes with CH3C[CH<sub>2</sub>PPh<sub>2</sub>]3 like [(triphos)RhCl(C<sub>2</sub>H<sub>4</sub>)], [(triphos)RhH(C<sub>2</sub>H<sub>4</sub>)], and [(triphos)Rh(C<sub>2</sub>H<sub>5</sub>)(C<sub>2</sub>H<sub>4</sub>)], provide model intermediates in the catalytic cycle for hydrogenation of alkenes.[4]
Triphos sometimes behaves as a bidentate ligand. Illustrative cases include fac-[Mn(CO)<sub>3</sub>Br(η<sup>2</sup>-triphos)] and [M(CO)<sub>4</sub>(η<sup>2</sup>-triphos)], where M is Cr, Mo, or W. Triphos serves as a tridentate-bridging ligand in an icosahedral Au13 cluster. The phosphine bridges three chlorogold(I) groups to form the tripod molecule of trichloro-1,1,1-(diphenylphosphinomethyl)ethanetrigold(I), CH3C[CH<sub>2</sub>PPh<sub>2</sub>AuCl]3.[5]
Related ligands
References
- . 1962 . 1490–1494 . 10.1039/JR9620001490 . 283. The preparation of di- and tri-tertiary phosphines . W. Hewertson . H. R. Watson . amp .
- Encyclopedia: Phosphorus Tripodal Ligands. Huttner, G.. Strittmatter, J.. Sandhoefner, S.. Comprehensive Coordination Chemistry II. 2004. 1. 297–322. 10.1016/B0-08-043748-6/01082-3. 9780080437484.
- Bianchini, Claudio . Marchi, Andrea . Marvelli, Lorenza . Peruzzini, Maurizio . Romerosa, Antonio . Rossi, Roberto . 1996 . Multiple Re-C Bonds at the [{MeC(CH<sub>2</sub>PPh<sub>2</sub>)<sub>3</sub>}Re(CO)<sub>2</sub>]+ Auxiliary . . 15 . 3804 . 10.1021/om9602264.
- Bianchini, Claudio . Meli, Andrea . Peruzzini, Maurizio . Vizza, Francesco . 1990 . Tripodal Polyphosphine Ligands in Homogeneous Catalysis. 1. Hydrogenation and Hydroformylation of Alkynes and Alkenes Assisted by Organorhodium Complexes with MeC(CH2PPh2)3. . 9 . 226–240 . 10.1021/om00115a035.
- Cooper, Mervyn K. . Henrick, Kim . McPartlin, Mary . Latten, Jozef L. . amp . 1982 . The synthesis and X-ray structure of trichloro-1,1,1-(diphenylphosphinomethyl)ethanetrigold(I) . . 65 . L185 . 10.1016/S0020-1693(00)93540-0 . 2.
- 10.1021/ja01022a020 . Low- and high-spin five-coordinate cobalt(II) and nickel(II) complexes with tris(2-diphenylphosphinoethyl)amine . 1968 . . L. . Bertini . I. . Journal of the American Chemical Society . 90 . 20 . 5443–5446 .
