Trichlorogermane etherates

Finally, the reaction of double germylation, such as formation of Cl3GeCH2CH2GeCl3 from ethylene and the etherate of trichlorogermane, is of great importance. 

The extraordinarily big shift of the nuclear quadrupole resonance frequency in the etherate of trichlorogermane in comparison with trichlorogermane itself (9 MHz from 23 to 14 MHz) can also be explained by a change in the coordination of the central atom to the trigonal-pyramidal form20. 

The exact determination of the acidic properties of trichlorogermane is experimentally difficult. First, it should be remembered that solvate-free trichlorogermane is a covalent compound. Only the presence of species such as an ether, amine or phosphine change the nature of trichlorogermane so that it easily ionizes. Hence, the acidic properties of H+[GenCl3] in the solvated form can only be estimated indirectly. 

The superacidic properties of trichlorogermane are clearly manifested in the properties of its etherates (vide infra) and the ability of DGeCl3 to participate in a deuterium-hydrogen exchange reaction with methylbenzenes32 (Section VIII.E). 

Interaction of trichlorogermane, and especially its etherates and aminates, with reactive organic halides results in nucleophilic substitution on organic halides by the trichlorogermyl group (equation 8)43,44. 

The organotin method was also used for preparation of 1-hydrogermatrane 187 from the trichlorogermane complex with ether . ... 

A surprising example of a double germylation reaction was first found in the aromatic series. Addition of two GeCls groups into 9,10-positions of anthracene and 9-methylantracene (MA) proceeds in the absence of ether, but require bubbling of air through the reaction mixture simultaneously with addition of trichlorogermane . ... 

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