Metal atom reactions with arsines

Mnltinnclear Re hydrides, in particnlar CO/phosphine complexes, with the hydride bridging two or three metals and componnds with H atoms bridging Re and other metals, for example, obtained from the reactions of Re polyhydrides with metal salts, have been reported. The coordination chemistry of hydrido/phosphine complexes has been extended, in a nnmber of cases, to related phosphite, phosphonite, or arsine complexes. ... 

The insoluble alkynylsilver complexes are regarded as coordination polymers (RC=CAg)co with cross-linking between the metal atoms and the ethynyls of adjacent RC=CAg units. Donor molecules (L) such as tertiary amines, phosphines and arsines can partly break down the polymeric structure. Thus the reactions of PhC=CAg with isopropylamine, trimethyl-, triethyl- or triphenylphosphine and triethylarsine yield the 1 1 complexes of the composition [(L)AgC=CR]49-51. 

In Table 2, comparisons between the complexes investigated in this study and a few other relevant iso-structural complexes from the literature suggest that the introduction of ligands with heavier donor atoms, such as arsines and stibines, leads to reduced steric crowding at the metal, creating more space for entering moieties in reactions such as oxidative addition. 

Reduction by Hydrazine. This was a very successful method for preparing the palladium (0) and platinum (0) derivatives with tertiary phosphines, phosphites, and arsines (4, 129, 130, 133). Also, the tetra-isocyanidenickel(O) compounds can be obtained at high yield in this way (132). In the case of platinum this reduction can give place either to zero valent derivatives (130) or to platinum (II) hydrides (49), according to the reaction conditions, the nature of the ligands, and the halogen atoms bound to the metal. This reduction is a very complicated reaction (186) in any case. 

Ring expansion is a common result of the reactions of cyclopolyphosphines and arsines with metal carbonyls e.g., Mo(CO)g combines with either cyclo-(MeP)5 or cyclo-(PhAs)g to form [Mo(CO)3]2[>/ , /<-cyclo-(RE)9] whose heavy-atom structure is that of trishomocubane, CnHi4, the same structure as found in and... 

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