Hydroalumination of dialkynylgermanes—synthesis of alkenyl–alkynylgermanes with intramolecular aluminium–carbon interactions
作者:Werner Uhl、Martina Rohling、Jutta Kösters
DOI:10.1039/c0nj00050g
日期:——
Reactions of dialkylaluminium hydrides, R2AlH [R = CH2CMe3, CMe3, CH(SiMe3)2], with di(phenylethynyl)germanes, R2Ge(CCâC6H5)2 [R = CH3 (1), C6H5 (2)], afforded mixed alkenylâalkynylgermanes, R2Ge(CCâC6H5)[C(AlR2)C(H)âC6H5] (3 to 7), by hydroalumination of one of the CC triple bonds. In all cases the cis-arrangement of the Al and H atoms across the resulting CC double bond was observed. Crystal structure determinations revealed relatively strong intramolecular bonding interactions between the coordinatively-unsaturated aluminium atoms and the α-carbon atoms of the intact triple bonds bearing a partial negative charge. This interaction is only prevented by application of the very bulky bis(trimethylsilyl)methyl substituent.
二烷基氢化铝 R2AlH [R = CH2CMe3, CMe3, CH(SiMe3)2] 与二(苯乙炔基)锗 R2Ge(CCâC6H5)2 [R = CH3 (1), C6H5 (2)] 的反应、R2Ge(CCâC6H5)[C(AlR2)C(H)âC6H5](3 至 7)。在所有情况下,都能观察到 Al 原子和 H 原子在 CC 双键上的顺式排列。晶体结构测定显示,配位不饱和铝原子与带有部分负电荷的完整三键的δ-碳原子之间的分子内键相互作用相对较强。只有通过使用非常笨重的双(三甲基硅基)甲基取代基才能阻止这种相互作用。