3-Silylated Cyclohexa-1,4-dienes as Surrogates for Gaseous and Harmful Hydrosilanes in Lewis-Acid Catalysis

自从Piers和他的同事发现Lewis酸B(C6F5)3在温和的反应条件下激活Si-H键的能力以来，已经导致了许多合成上有用的应用。我们的实验室最近首次发现，相同的强刘易斯酸能够激活3-硅化环己-1,4-二烯中的双烯丙基C-H键，从而催化氢硅烷的释放，同时形成苯。该方法对于生成气态、高度易燃和/或有害的氢硅烷特别有吸引力。易于获得的3-硅化环己-1,4-二烯是易于处理的液体，代表氢硅烷替代品。B(C6F5)3催化的硅烷释放和随后的Si-H键激活的结合为烯烃离子转移硅氢化的发展铺平了道路。我们计划在这些基本发现的基础上进一步完善我们的新方法，并扩大其在lewis酸催化中的应用。主要目标将是确定合适的转移试剂/硼路易斯酸组合，以释放和转移功能化硅烷。

The ability of the commercially available Lewis acid B(C6F5)3 to activate Si-H bonds under mild reaction conditions has led to a number of synthetically useful applications since its discovery by Piers and co-workers. Our laboratory recently disclosed for the first time that the same strong Lewis acid is able to activate a bisallylic C-H bond in 3-silylated cyclohexa-1,4-dienes, thereby catalyzing the release of hydrosilanes with concomitant formation of benzene. This procedure is particularly attractive for the generation of otherwise gaseous, highly flammable and/or harmful hydrosilanes. The readily available 3-silylated cyclohexa-1,4-dienes are easy-to-handle liquids and represent hydrosilane surrogates. The combination of the B(C6F5)3-catalyzed silane release and subsequent Si-H bond activation then paved the way to the development of an unprecedented ionic transfer hydrosilylation of alkenes. We plan to elaborate our new methodology further and expand its application in Lewis-acid catalysis based on these fundamental findings. The major goal will be the identification of suitable transfer reagent/boron Lewis acid combinations for the release and transfer of functionalized silanes.