Halides arsine, complexes

These ligands all form 1 1 complexes with platinum(II) halides which are non-conductors, monomeric and, in the solid state, contain one coordinated and two free double bonds. Proton n.m.r. data indicate that all three double bonds are equivalent in solution due to a rapid equilibrium between bonded and non-bonded —CH=CH2 groups. The phosphine and arsine complexes PtBraL (L = tvpp, tvpa) react with two equivalents of bromine giving what are believed to be platinum(II) species containing one coordinated double bond and two —CHBr-CHaBr groups arising from the saturation by bromine of the two free double bonds. 

A very large number of phosphine, phosphite, stibine, and arsine complexes of type four-coordinate [NiX2(ER3)2] and five-coordinate [NiX2(ER3)3] (X = halide) have been reported, although this area is dominated by complexes of tertiary phosphines. The complexes [NiX2(ER3)2] can be either tetrahedral (67) or square-planar (68), depending upon the electronic and steric effect of the coordinated phosphine, arsine, and stibine ligands (see Section 2). ... 

Arsines. The ligand o-phenylenebis(dimethylarsine) (diars) has been used to complex actinide halides. The complexes PaCl4(diars) and UCl4(diars) have been reported. Both are produced by the reduction of pentavalent precursors in solution upon addition of the arsine. ... 

The first fully characterized germanium(IV) arsine complex, (Me3As)2GeCl4, can be prepared from the direct reaction of the arsine with halide, and has trans structure with Ge-As of... 

Complexity in the manganese and rhenium pentarbonyl halides substitution arises from the fact that these decompose in inert solvents to form the halogen-bridged dimers [M(CO)4X]2. Both monomers and dimers react with phosphines, arsines, pyridine, aniline etc. to give the disubstituted compounds M(CO)3XL2. Thus three final products or any mixture of them may be obtained, depending upon the precise reaction conditions... 

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