Silicon hydrides atomic germanium

The reactions of atoms or radicals with silicon hydrides, germanium hydrides, and tin hydrides are the key steps in formation of the metal-centered radicals [Eq. (1)]. Silyl radicals play a strategic role in diverse areas of science, from the production of silicon-containing ceramics to applications in polymers and organic synthesis.1 Tin hydrides have been widely applied in synthesis in radical chain reactions that were well established decades ago.2,3 Germanium hydrides have been less commonly employed but provide some attractive features for organic synthesis. 

As with silicon hydrides, the reaction of atoms or radicals with germanium hydrides is the key step for the majority of reactions forming germyl radicals. However, kinetic data for the reactions of organic radicals with germanium hydrides in solution are limited to carbon- and oxygen-centered radicals. 

Silicon forms numerous hydrides that have counterparts in the hydrocarbon series. However, the silanes are named with respect to the number of silicon atoms present. For example, Si2Hs is known as disilane, Si3H8 is trisilane, and so on. The situation is similar for the germanium hydrides. 

Lanthanide alkyl and aryl complexes react with organoelement hydride compounds, such as hydrides of silicon, germanium, and tin, and so on, resulting in a hydride transfer to the lanthanide metal atom. Among the organoelement hydrides, organosilanes are the most popular source of the hydride. 

Hydrogen atom transfer reactions involving 17-electron hydrides have been considered in a number of cases [54, 58, 86, 99, 112] as alternatives to proton and electron transfers, on the basis of the known atom transfer processes of hydride compounds of tin, germanium, and silicon. In addition, as discussed in section 6.4.3, there is some evidence for M-H bond weakening upon oxidation, suggesting that the homolytic rupture of this bond may take place under favourable circumstances. 

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