Development of Synthetic Methods for the Silaallene Cationic Species and the Related Compounds and Their Application Reactions

首先，我们开发了高效的二芳基单炔基氟硅烷和二酮基二芳基硅烷的合成方法如下。芳基锂与四氯硅烷反应生成单芳基三氯硅烷，再与其他芳基锂反应得到二芳基二氯硅烷。卤素交换反应(Cl→F)后，二芳基二氟硅烷与炔基锂反应得到所需的二芳基单炔基氟硅烷。它们与其他炔基锂的类似反应以极高的产率提供了相应的炔基取代的二烷基二芳基硅烷。含有t-Bu、TiP、苯基和氟原子的单炔基单芳基氟硅烷在0℃下与t-BuLi反应，然后在室温或回流条件下生成1-硅烯。1-硅烯与酮、醛和亚胺反应，分别得到相应的1，2-氧杂硅烷和1，2-氮杂硅烷。不同种类的炔基取代的二芳基二芳基硅烷用双环戊二烯基二茂铁-乙烯络合物处理，然后用3N HCl酸化，以较好的产率得到相应的区域和立体选择性的硅环丁烯。硅环丁烯用四丁基氟化铵脱硅分别得到立体选择性的不对称共轭双烯和三烯，产率很高。

First, we have developed highly efficient synthetic methods for diarylmonoalkynylfluorosilanes and dialkynyldiarylsilanes as follows. Reaction of aryllithiums with tetrachlorosilane gave monoaryltrichlorosilanes, which were treated with other aryllithiums to afford diaryldichlorosilanes. After halogen exchange reaction (Cl→F), treatment of the resulting diaryldifluorosilanes with alkynyllithiums gave the desired diarylmonoalkynylfluorosilanes. Their similar reactions with other alkynyllithiums furnished the corresponding alkynyl-substituted dialkynyldiarylsilanes in excellent yields. Treatment of the monoalkynylmonoarylfluorosilane bearing t-Bu, Tip, phenylalkynyl, and fluorine atom with t-BuLi at 0℃ and then at room temperature or under reflux generated a 1-silaallene. The 1-silaallene was in situ allowed to react with ketones, aldehydes, and an imine to give the corresponding 1,2-oxasiletanes and 1,2-azasiletane, respectively. Treatment of the differrent kinds of alkynyl-substituted dialkynyldiarylsilanes with biscyclopentadienylzirconocene-ethylene complex followed by acidification with 3N HC1 gave regio-and stereoselectively the corresponding silacyclobutenes in good yields. Desilylation of the silacyclobutenes with tetrabutylammonium fluoride afforded stereoselectively unsymmetrical conjugated dienes and trienes in excellent yields, respectively.