“有机硅”在自然界中并不存在,但现代化学很难想象没有硅与碳结合的情况。虽然含硅商品化学品(例如通过“直接工艺” 1,2,3,4产生的那些)看起来很简单,但选择性制备芳基取代和烷基取代(官能化)硅化合物(称为硅烷)并非易事。氯硅烷如 Me 4− n SiCl n ( n = 1–3) 以及 SiCl 4 ( n = 4) 是合成含硅分子的常见起点。然而这些方法常常遇到具有挑战性的分离问题5 。相反,具有四个烷基的硅烷被认为是合成的死角。在这里,我们介绍了芳烃离子催化的卤代脱烷基化反应,可有效地将 Me 4 Si 和相关的季硅烷转化为各种官能化衍生物。该反应使用烷基卤和芳烃(共)溶剂:烷基卤是卤化物源,最终与芳烃进行弗里德尔-克来福特烷基化以再生催化剂6 ,而芳烃离子则充当强布朗斯台德酸原脱烷基化步骤7 。例如,在硅药物前体的合成中,证明了自上而下的卤代烷基化方法相对于报道的自下而上程序的优势。此外,连接到烷基链上的相当惰性的Me
Photo-inducedelectrontransfer reactions of tetraalkylsilanes, -germanes, and -stannanes with aromaticnitriles afforded alkylated products. The mechanism was investigated by use of a radical clock.
In the presence of an iridium 3,4,7,8-tetramethyl-1,10-phenanthroline catalyst, a methyl group on the silicon atom of alkyltrimethylsilanes undergoes selective C-H borylation with bis(pinacolato)diboron in cyclooctane at 135 degrees C to give alkyl(borylmethyl)dimethylsilanes. The C-H borylation of tetramethylsilane takes place efficiently at 100 degrees C. Permethyloligosilanes can also undergo C-H borylation without cleavage of the Si-Si bonds.
Larsson; van Gilse van der Pals, Svensk Kemisk Tidskrift, 1951, vol. 63, p. 179
作者:Larsson、van Gilse van der Pals
DOI:——
日期:——
Gomzina, N. A.; Kochina, T. A.; Nefedov, V. D., Russian Journal of General Chemistry, 1994, vol. 64, # 7.1, p. 1011 - 1013
作者:Gomzina, N. A.、Kochina, T. A.、Nefedov, V. D.、Sinotova, E. N.