Silicon—germanium bonds reactions with

Silicon and germanium hydrides react with cobalt, manganese and rhenium carbonyls affording complexes having a silicon (or germanium)-metal bond. These reactions, described previously for inactive compounds have been used in the synthesis of optically active silyl and germyl-transition metals ... 

Electrophiles such as halogens may cleave the transition metal-silicon (or germanium) bonds. We have already seen that in the case of the hydrido complexes they induce deinsertion reactions with retention of configuration at silicon (cf. Sect. 3.1). 

Germanium and silicon hydrides should be even more selective toward alkoxyl radicals relative to carbon radicals. Indeed, while silicon hydrides react rapidly with alkoxyl radicals, reactions with carbon radicals are too slow to propagate chains. The rapid addition of silyl and germyl radicals to C—O bonds is a possible complicating reaction. 

A characteristic feature of the exchange reactions on germanium as compared to silicon is the much faster rate of equilibration observed for analogous germanium compounds. But again, in view of the stability of germanium-carbon bonds with respect to redistribution and the ease with... 

Reactivity is an intriguing aspect of these complexes not only because of the previously mentioned unique bonding mode, but also because these complexes can serve as good models for surface-bound divalent silicon and germanium species. Unfortunately, only a limited number of the reactions with small molecules and catalytic reactions have been reported so far. In contrast, the dynamic behaviors and isomerization reactions of these complexes, which give plentiful information about their chemical properties, are well documented. 

The reactions of germanium and tin compounds with HFA are very similar to those of silicon compounds. But because of differences in polarity and bond strengths some reactions yield products different from those of their silicon analogues. 

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