Phosphine, tris complex with

The first polyphosphino maeroeyeles designed speeifieally for use as transition metal binders were reported in 1977 in back-to-baek eommunications by Rosen and Kyba and their eoworkers. The maeroeyeles reported in these papers were quite similar in some respeets, but the synthetic approaches were markedly different. DelDonno and Rosen began with bis-phosphinate 18. Treatment of the latter with Vitride reducing agent and phosphinate 19, led to the tris-phosphine,20. Formation of the nickel (II) complex of 20 followed by double alkylation (cyclization) and then removal of Ni by treatment of the complex with cyanide, led to 21 as illustrated in Eq. (6.15). The overall yield for this sequence is about 10%. 

Nickel(0) complexes with water-soluble phosphines have attracted interest in the context of homogeneous catalysis. A comprehensive study of the coordination chemistry of tris(sodium-m-sulfonatophenyl)phosphine (1039) has appeared.2504 The complexes [Ni(CO)2(1039)2] 6HzO have been made by reaction of (1039) with Ni(CO)4 under phase-transfer conditions, and the homo-leptic [Ni(1039)3]-9H2O has been made from Ni° precursors and (1039) under phase-transfer conditions, or from NiCl2, (1039), and BH4 in water. A related complex [Ni(CO)2(1040)2] with the bidentate ligand (1040) has also been studied.2505... 

More than 35 years ago, it was reported that the reaction of tri-methylphosphine with the cyclotetraphosphine (CF3P)4 affords the phosphine-phosphinidene complex, Me3P —> PCF3 (43). More recently, it has been demonstrated that stable carbenes are sufficiently nucleophilic to effect the depolymerization of cyclopolyphosphines and cyclopolyarsines to produce carbene-pnictinidene complexes 66-70, the first examples of p-block pnictinidenes (44, 45). Two extreme canonical forms, 71 and 72, can be written for such species. Structure 71... 

Ellis, J.W., Harrison, K.N., Hoye, P.A.T., Orpen, A.G., Pringle, P.G., and Smith, M.B., Water-soluble tris(hydroxymethyl)phosphine complexes with nickel, palladium, and platinum. Crystal structure of Pd P(CH2OH)3 4].cntdot.CH3, Inorg. Chem., 31, 3026, 1992. 

Tris(trimethylsilyl)silane reacts with phosphine sulfides and phosphine selen-ides under free radical conditions to give the corresponding phosphines or, after treatment with BH3-THF, the corresponding phosphine-borane complex in good to excellent yields (Reaction 4.45) [82]. Stereochemical studies on P-chiral phosphine sulphides showed that these reductions proceed with retention of configuration. An example is given in Reaction (4.46). 

Aqueous biphasic catalysis is also used in homogeneous hydrogenations.117-119 In new examples Ru clusters with the widely used TPPTN [tris(3-sulfonatophenyl) phosphine] ligand120 and Rh complexes with novel carboxylated phosphines121 were applied in alkene hydrogenation, whereas Ru catalysts were used in the hydro-genation of aromatics. Aerobic oxidation of terminal alkenes to methyl ketones was carried out in a biphasic liquid-liquid system by stable, recyclable, water-soluble Pd(II) complexes with sulfonated bidentate diamine ligands.124... 

Complexes with tri- and tetra-dentate open-chain ligands containing tertiary phosphines and arsines,... 

The tetrakis-phosphino and -arsino complexes reported in Table 3 have very different thermal and air stabilities. In general, complexes with alkyl-phosphines and -arsines are air-unstable or pyrophoric. The tetrakis(arylphosphino) complexes (but not the bis or tris derivatives) are moderately air- and heat-stable, and the tetrakis phosphites may be handled in the atmosphere. Ni(PF3)4 is a stable liquid compound, whereas Ni(PCl3)4 and Ni(PBr3)4 are solids and stable only in dry air. 

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