Hydrido copper

Recently, a somewhat different synthetic approach has been reported. Halcrow et al. (215) synthesized a series of five-coordinate copper(II) complexes comprising a tridentate tris(pyrazolyl)borate ligand and a bidentate phenol derivative. Neutral complexes [Cun(TpPh)(bidentate phenolate)] were synthesized and structurally characterized [Tpph] = hydrido-tris(3-phenylpyrazol-l-yl)borate. The species [Cun(TpPh)(2-hydroxy-5-methyl-3-methylsulfanylbenzaldehydato)] can electro-chemically be converted to the (phenoxyl)copper(II) monocation, which has been characterized in solution by UV-vis spectroscopy. It displays two intense absorption maxima at 907 nm (e = 1.2 x 103 M 1 cm-1), and 1037 (1.1 x 103 M l cm-1), resembling in this respect the radical cofactor in GO (Fig. 7). 

Listed as hydrido (triphenylphosphine)copper(I) hexamer Aldrich catalog 36497-5. 

Additives are also used to improve the solubility of halide donors [382, 383]. Metal(II) halides such as magnesium chloride, calcium chloride, barium chloride, manganese chloride, zinc chloride and copper chloride etc. are used as halide sources. In order to increase the solubility of the halides they are reacted with electron donors which have been previously described for the increase of solubility of Nd-components [338,339]. The number of catalyst components is further increased if two Al-compounds (alumoxane + aluminum (hydrido) alkyl) are used. In addition, a small amount of diene can also be present during the preformation of the different catalyst components as described by JSR. In some catalyst systems the total number of components reaches up to eight [338,339]. Such complex catalyst systems are also referred to in other JSR patents [384,385] (Sect. 2.2.6). 

Other reducing agents, such as hexakis[hydrido(triphenylphosphine)copper(I)] in benzene, H2/Pd-C in ethanol, lithium triethylborohydride in THF, failed to give the desired product. 

The action of PF3 and hydrogen at high temperatures and pressures upon mixtures of anhydrous rhodium trichloride and copper forms (equation 57) the colorless liquid [RhH(PF3)4] (b.p. 89°C/ 725 torr).32-35-208 The liquid decomposes slowly at 20°C to form [Rh(PF2)(PF3)3]2, but on heating to 140nC it decomposes to rhodium metal.32 The hydrido complex can also be formed by the action of strong acids on the potassium salt K[Rh(PF3)4] (equation 58).34... 

The reductive fluorophosphination of metal halides in the presence of copper and hydrogen gas at high temperature and pressure offers a useful synthetic route for a number of hydrido trifluorophosphine metal complexes (method A). 

Copper hydride ate complexes. Semmelhack has reviewed a number of these complexes, prepared usually from CuBr or Cul and various complex metal hydrides. They function as hydride transfer reagents, but show differences in behavior. One early complex of this type is hydrido(tri-n-butylphosphine)-copper(l)-HCu(PBu3), prepared by Whitesides (3, 154). The structure or mode of reaction of the other related complexes is not clear. 

Neutron diffraction structure analysis of a hexanuclear copper hydrido complex, H6Cu6[P(p-tolyl)3]6 An unex- 27. pected finding. J. Am. Chem. Soc. 1989, 111. 3472-3473. 

Ci8H22N208Rh2, Tetra- -acetato-bis(pyridinerhodium(lI)), 44B, 882 Ci8H22Nb30iOf Hydrido-/X3"Oxo-tri Ai hydroxo-tri-Ai"formato-tri-triangulO cyclopentadienylniobium(IV), 39B, 710 Cl8H2aCuI2N2O11, Copper(ll) m-iodohippurate pentahydrate, 41B, 1121 Ci8H26CuOi2f Copper(II) p-methoxyphenoxyacetate tetrahydrate, 41B, 1022... 

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