Germanium transition metal

Chemical and stereochemical properties of compounds with silicon- or germanium-transition metal bonds. E. Colomer and R. J. P. Corriu, Top. Curr. Chem., 1981, 96, 79-107 (68). 

Colomer, E., and Corriu, R. J. P. Chemical and Stereochemical Properties of Compounds with Silicon or Germanium-Transition Metal Bonds, 96, 79-110 (1981). 

Chemical and Stereochemical Properties of Compounds with Silicon or Germanium-Transition Metal B(nids... 

Cleavage of Silicon (or Germanium)-Transition Metal Bonds by... 

Complexes with silicon (or germanium)-transition metal bonds in which silicon or germanium is optically active are very stable both chemically and optically. 

The stereochemistry of displacement of chiral germyl ligand in germanium transition metal complexes [which has been reviewed elsewhere (12)] will also be discussed here, since silicon and germanium resemble each other and since complementary experiments have been undertaken. 

The less common heteroatoms are those other than nitrogen, oxygen and sulfur (arid selenium and tellurium which are treated alongside sulfur), i.e. phosphorus, arsenic, antimony, bismuth, the halogens, silicon, germanium, tin, lead, boron and the transition metals. 

In some materials, semiconductors in particular, interstitial atoms play a crucial role in diffusion. Thus, Frank and Turnbull (1956) proposed that copper atoms dissolved in germanium are present both substitutionally (together with vacancies) and interstitially, and that the vacancies and interstitial copper atoms diffuse independently. Such diffusion can be very rapid, and this was exploited in preparing the famous micrograph of Figure 3.14 in the preceding chapter. Similarly, it is now recognised that transition metal atoms dissolved in silicon diffuse by a very fast, predominantly interstitial, mechanism (Weber 1988). 

Mixed alkali-metal chalcogenolates have been synthesized for main group elements, such as aluminium,54,55 germanium, and tin as (6) (Scheme 2),56 or transition metals such as zirconium,57 60 iron,61,62 vanadium,63 nickel,64 rhenium,65 and cobalt,66 or lanthanide metals.67,68... 

The single-bond compounds between Si, Ge, and Sn and chalcogens (S, Se, Te) are reactive and used as synthetic intermediates in the synthesis of organic compounds, organochalcogen compounds, organo-silicon, -germanium and -tin compounds, and transition metal-chalcogen complexes and clusters. 

Alkynes react with the bulky germanium hydride (MejSdjGeH to selectively yield (Z)-alkenes (Equation (105)).67 The hydrogermylation of alkynols or alkynes can be catalyzed by a rhodium complex (Equation (106), Table 18) and some of the intermediates were identified (Scheme 16).132 Similar rhodium species react with alkynes to yield alkenyl complexes,133 and other transition metal complexes have been employed as hydrogermylation catalysts including those containing palladium.134,135... 

A few clusters of interest containing germanium and transition metals have been reported.136-138 Dimethylgermane was found to replace only the bridging carbonyls between cobalt in a mixed germanium/cobalt/iron cluster complex (Equation (107)), and replacement of the carbonyl bridging the iron metal centers was not observed.137 A similar reaction leads to replacement of a bridging carbonyl in a mixed cobalt/silicon cluster (Equation (108)).136... 

Germylenes can be released thermally in the presence of a transition metal complex leading to the formation of a germanium-metal bond (Equation (193)).239 The reaction occurs at room temperature when a germylsilane is used as the synthon (Equation (194)).240... 

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