Hypervalent germanium compounds

H. Compounds having a Hypovalent and Hypervalent Germanium Atom... 

Hypervalent germanium derivatives are compounds having penta-, hexa- and sometimes heptacoordinate germanium atom. Numerous publications are devoted to inorganic and pseudo-organic (with no C—Ge bonds) derivatives of this type159,488,518,524-528. 

The purpose of the present chapter is to review the investigations dealing with the synthesis, structure and reactivity of hypervalent germanium, tin and lead compounds. The structures and properties of these compounds still remain a challenge. Many novel and unusual structures were elucidated by the X-ray diffraction technique. 

This study demonstrates the utility of amidinate ligands for the synthesis of hypervalent silicon and germanium compounds, and also, for the synthesis of low-valent germanium compounds. In addition, surprising results with dianionic amidinate ligands [N-C(R)—NR ] at silicon centers are documented. 

Summary The degradation rate of biologically active hypervalent silicon and germanium compounds (atranes) was investigated under various pH conditions. Stimulating effects on proliferation and reparation processes in experimental animals were demonstrated. 

Hypervalent compounds of organic germanium, tin and lead derivatives... 

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