Complexes bicoordinated

Table 4.44. Properties of bicoordinate metal-ligand complexes for M = Ir+ (see Fig. 4.86) binding energy A E and geometrical parameters (bond length Rml...

Table 4.45. Properties of bicoordinate metal ligand complexes for M =...

The properties of bis(di-rm-butylphenylphosphine)palladium(0) are described with those of the other bicoordinates complexes (see below). 

H(D) atoms were used in Refs. [70,75] as a paramagnetic probe of the activated silica surface. The structure of complexes formed, (=Si-C))2Si -H(D), was found by ESR method. Taking into account the procedure of obtaining these PCs, we may conclude that they are formed due to accepting H(D) atoms by bicoordinated silicon atoms ... 

The synthesis of low-dimensional solids has become more important than ever before, both to chemists and physicists. In the catenation of metal ions, the catenating blocks are usually polynucleating ligands. The 1,2,4-triazole ligand acts in most of its metal complexes as a 1,2-bicoordinating ligand. In this type of coordination, linear polynuclear complexes are formed. 

Two-coordinate complexes still remain a rarity in transition metal chemistry. Recently a few bicoordinate complexes of palladium(0) and platinum(0), ML2 [M = Pd, Pt L=PPh(t-Bu)2 or P(cyclo-C6Hu)3] have been reported, and X-ray studies reveal that they have almost linear structures. 

The bicoordinate complexes described here are soluble in benzene and hexane. The Pd[P(t-Bu)3]2 complex is stable in air in the solid state, whereas... 

The conclusions we can draw primarily deal with the mechanistic duality in reactions of acetals and those factors which control the pathways. We have found that for the two limiting mechanisms operating in the reaction of acetals with allylsilanes and allylstannanes that 1) mefiyl, ethyl and isobutyl acetals react via an SN2-like mechanism with monocoordinate Lewis acids, 2) isopropyl acetals react via an SNl-hke mechanism with monocoordinate Lewis acids and 3) methyl acetals react slowly via an SNl-like mechanism with bicoordinate Lewis acids after initial formation of a stoichiometric Lewis-acid acetal complex. 

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