Germanium tetrahalide

Redistribution Reactions between Tetraalkyl- or Tetraarylgermanes and Germanium Tetrahalides... 

The method of alkylation of germanium tetrahalides in the presence of catalysts251 is more effective ... 

Bis(trifluoromethyl)mercury was found to react at elevated temperatures with both tin and germanium tetrahalides, resulting in a number of CF3-containing compounds including the fully substituted derivative of germanium, (CF3)4Ge Eq. (5)1. The reaction of tin tetrabromide with (CF3)2Hg, on the other hand, yielded only CF3SnBr3 and (CF3)2SnBr2, as shown in Eq. (6) (102). 

Bis(/i,-germyl)iron carbonyl complexes without a metal-metal bond were synthesized by the reaction of Fe(CO)5 with germanium tetrahalides and later by an alternate route involving high temperature reaction of Fe(CO)5 with a bis(halogermyl)iron carbonyl complex. Ferrous chloride is a byproduct of these reactions (equation 32)86-89. 

Synthesis of alkyl (or aryl) halogermanes (56) from a germanium tetrahalide (54) occurs in two steps (Scheme 9.18) [56]. The most difficult to realize, and the least selective, is the second, i.e. the redistribution between alkyl (or aryl) and halide substituents of I Ge and GeX4 compounds. Depending on the ratio of these two... 

The other methods are that organogermanium compounds are prepared by heating germanium tetrahalides with alkyl halides in the presence of a copper catalyst [12]. 

Which would you expect to be the more covalent, the germanium tetrahalides or the germanium dihalides Briefly explain your answer. 

I Grignard reaction with germanium tetrahalides (IA) in diethyl ether or (IB) in tetrahydrofuran ... 

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