Germanium dihalides

Although direct combination of the elements is feasible, germanium dihalides are usually prepared by... 

Table 3. Heats of formation and atomization of gaseous germanium dihalides, and stabilities...

Reactions of Germanium Dihalides. Due to its ease of preparation, Gel2 pro-sesses the best characterized reaction chemistry of the dihalides of germanium. 

GeBr2 is observed to imdergo similar reactions 124 No direct reaction was observed between carbonyl compounds and germanium dihalides 125 ... 

At higher temperatures this reaction is reversed. The germanium dihalides are all strong reducing agents. The solids possibly have bridged structures ... 

Germanium. The germanium dihalides are quite stable entities. GeF2, a white crystalline solid (m.p. 111°) is formed by action of anhydrous HF on Ge in a bomb at 200° or by reaction of Ge and GeF4 above 100°. It is a fluorine-bridged polymer, the Ge atom having a distorted trigonal-bipyramid... 

The other germanium dihalides are less stable and less well studied, but salts of the ion GeClj" are well known.53 The sulfide, GeS, and a yellow amphoteric hydroxide, Ge(OH)2, are known the latter is precipitated by base from GeIV solutions in H2S04 that have been reduced by zinc. 

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

Another general method consists in the insertion of germanium dihalides into metal-metal bonds, giving M-Ge-M configurations ... 

More recently, the doubly lithiated derivatives of [4.1.1]- and [3.1.1]propellasilanes underwent bridging metathesis at the bicyclobutane ends with dihalides of germanium, tin and transition metal titanium, to give the corresponding highly strained metallacyclic propellanes (equation 7)29. 

Hal = F, Cl, Br, I), a solid state reaction between germanium sulfide and suitable lead dihalides at ca 570 K was used304-306. The observed IEs, corresponding to ionizations from the valence shell MOs, are presented in Table 11. 

---