摘要:
The B-(triphenylgermyl)borazines 4a and 4b, the 1,2-bis(dimethylamino) -1,2-bis(triphenylgermyl)-diborane(4), 5, and the (2,2,6,6-tetramethylpiperidino)(triphenylgermyl) boranes 6 and 7 were prepared by allowing LiGePh3 to react with the corresponding B-bromoborazines and amino-chloroboranes, respectively. BH3 dissolved in thf readily adds to LiGePh3 generating Li(H3BGePh3), 8a, in thf solution. Addition of N-bases to the solution of 8a produced (tmen thf)Li(H3BGePh3), 8b, and dimeric (py)(2)Li(H3BGePh3), Sc. The borazine ring in 4b is distorted into a boat shape. In 5 the NBGe planes are twisted against each other by 85 degrees. Comparison with analogous (triphenylstannyl)boranes points to a more pronounced steric effect of the Ph3Ge group over the Ph3Sn group due to the shorter B-Ge bond. A fairly short B-Ge bond is found for the (triphenylgermyl)trihydroberates. The molecular structure of (Et2O)(3)LiGePh3 shows compressed C-Ce-C bond angles. Its molecular parameters fit well into the series LnLiEPh3 (E = Si, Sn, Pb).