Triphenylphosphine ligand

Homogeneous hydrogenation catalyzed by the four-coordinated rhodium complex, Rh[(C6H5)3P]3Cl, has been particularly well investigated. With this catalyst, the first step is formation of the six-coordinated rhodium hydride of known configuration, 16, in which we abbreviate the ligand, triphenylphosphine, (C6H5)3P, as L ... 

Figure 31-2 Merry-go-round diagram that summarizes the steps in the hydrogenation of ethene by Rh[(C6H5)3P]3CI. The key features are the flow of reactants into and the products out of the cycle, the loss and regaining of the ligand, and the regeneration of the catalyst. The ligand triphenylphosphine is represented by L.

In method (b), (1) is again formed the ligand triphenylphosphine then promotes migratory insertion to give the anionic iron acyl complex (4). Reaction with another alkyl halide gives a complex (5) corresponding to (3) above. 

The regioselectivity of hydroesterification of alkyl acrylates or aromatic olefins catalyzed by [PdCl2L2] complexes (L = phosphine ligand) could be largely controlled by variation of the ligands. Triphenylphosphine promotes preferential carboxylation to the branched isomer, whereas with bidentate bisphosphines the linear product is produced overwhelmingly [14]. 

Both reactions could be carried out in a liquid-liquid two-phase system with the advantages of easy product separation and efficient catalyst recycling. In the presence of a water-soluble ruthenium catalyst with the ligand triphenylphosphine trisulfo-nate, simultaneous extraction of the organic product phase by N,N-dibutylformamide can be achieved [87, 88]. 

The iridium complexe hydrides so far reported, belong to the type where L may be triphenylphosphine (1) or the diethylphenylphosphine (2), Using as ligand triphenylphosphine we have now prepared the unsaturated hydride as well as the hydridocarbonylphosphineiridium compounds... 

Ligands triphenylphosphine (PPhs), - bis(diphenylphosphino)-methane (dppm), (/n-sulfonatophenyl)diphenylphosphine (TPPMS) and 1,5-cyclooctadiene (COD). 

Other Reactions of Inorganic Ligands Triphenylphosphine removes one sulphur atom from the thiocumato-complex (12), giving triphenylphosphine sulphide, SPPhg. The reaction is second-order, with an activation energy of 7.8 1.0 kcal mol-. ... 

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