Wurtz reactions polygermanes

Polygermanes have been prepared by the Wurtz-type coupling reaction of diorganogermaniumdichlorides, R2GeCl2 [11-13]. The latter are most readily synthesized by an equilibration between R4Ge and GeCU [12] (see Eq. 8.1). 

The Wurtz-type coupling reaction of R2GeCl2 with sodium in high-boiling solvents such as toluene at reflux temperatures affords polygermanes (see Eq. 8.2). 

Synthesis. Polygermanes (11) were prepared in the mid-1980s by Wurtz coupling techniques similar to those used to prepare the silicon analogues (eq. 13) (1). A variety of alkyl and aryl derivatives can be prepared by this method but the harsh reaction conditions are not tolerant of many functional groups (53). 

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