Complexes containing phosphine ligands

Tetra- and pentachloro- and tetrabromo-complexes of Tc(IV) containing different phosphines were prepared by reaction of technetium tetrahalogenide with the pertinent phosphine [356] or by refluxing TcOj with the phosphine in ethanol in the presence of hydro-halogenic acid [386]. Halogenophosphine complexes are summarized in Table 12.12. A. 

ClHlipICX Color Geometry (Configuration) Magnetic moment /reirlB.M.l References 

Similar to triphenylphosphine, the tris(2-cyanoethyl)phosphine (cep) forms complexes with technetium in which cep is a monodentatc ligand. Reaction of TcOi in aqueous ethanolic solution containing hydrochloric acid yielded a blue, microcrystal-linc solid of [TcCl4(cep)2]° with a melting point of 175 °C [303]. 

Some structural data of Tc(IV) complexes are reviewed in Table 12.13.A. 

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In many cases, the driving force behind studies of Ru or Os complexes containing phosphine ligands incorporating O-donors is potential application in catalysis. A common feature of many of the P,0-bound ligands described in this section is their partial lability, with the conversion of a P,0- to P-coordinated ligand as another Lewis base such as CO or RNC displaces the O-donor. 

The majority of nickel(I) complexes contain phosphine ligands, or closely related ones, and have tetrahedral or tbp structures. They are paramagnetic as expected for d9 configurations. The tetrahedral compounds NiX(PPh3)3 (X = Q, Br, and I) were among the first of this sort to be isolated they decompose only slowly in air and are stable for long periods of time under nitrogen. Electrolytic reductions of... 

Wn Chalcogenides with CO Ligands and the Related Compounds 4.8.63.1 Complexes containing phosphine ligands... 

Allylic ethers and alcohols have long been known to react with Grignard reagents in the presence of an appropriate Ni-based complex containing phosphine ligands [26]. These reactions are related to the well-studied Pd-catalyzed allylic substitution reactions that utilize soft nucleophiles [27], and a number of important mechanistic studies on the stereochemical outcome of this class of transformations have been carried out [28]. 

Chatt was one of the early pioneers in furthering our understanding of the nature of the coordinate link in metal complexes containing phosphine ligands. ... 

A majority of the carbonylations of organic halides have been conducted with aryl and vinyl halides, although reactions have been developed with benzylic halides and even purely aliphatic halides. A majority of the reactions of aryl halides have been conducted with aryl iodides, although a few reactions have been reported with electron-poor aryl bromides. Few examples of these reactions have been reported with electron-rich aryl bromides or aryl chlorides. Most of these reactions have been conducted with palladium complexes containing phosphine ligands. 

Stereo and regiodefined alkenylmetals containing A1 or Zr react with aryl and alkenyl iodides and bromides in the presence of catalytic amounts of Ni complexes containing phosphine ligands such as PPhj, to give the corresponding coupling products [81-84]. 

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