Germanium bond order

By using a sum of the bond order of 4 in the hypervalent O — GeCCl2—Cl fragment and a value of 1 for the axial bonds, values of 0.92 and 0.87, respectively, are obtained for the coefficient c. These and the previously calculated value of 0.80 for penta- and hexacoordinate Ge compounds475 are lower than c for tin (1.20475). This demonstrates a decreased tendency toward expanding the coordination sphere of germanium atom compared to that of tin476. 

Cross experiments between R4 nGe(SiCl3)n and R4 nGeCl (R = Me, Et and n = 1, 2) with catalytic amounts of triethylamine indicate a dynamic SiCb (or SiCb) transfer equilibrium reaction ( C and Si NMR evidence). The equilibrium of these reactions is very dependent on the number and quality of the organic substituents bonded to germanium. In order to study this dependence, all 12 possible variations of these reactions between R4 nGe(SiCl3)n and R4 nGeCln (R = Me, Et and n = 1, 2) were carried out and investigated with the help of and Si NMR. One example of these reactions is presented in Scheme 2. 

The tetrametalmethane species la,b which contains carbon bonded to germanium, silicon, tin, and boron have been obtained (Equations (5) and (6)),7 and the overall yield of la,b varies with the order of attachment of the different metals. 

List these bonds in order of increasing polarity P-F, S-F, Ga-F, Ge-F (F, fluorine, atomic number g P, phosphorus, atomic number 15 S, sulfur, atomic number 16 Ga, gallium, atomic number 31 Ge, germanium, atomic number 32) ... 

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