hydrosilanes underwent the DIBAL-H-promoted cyclization to benzosiloles. When 1-hydrosilyl-2-[2-(trimethylsilyl)ethynyl]benzenes were used as substrates, a substoichiometric amount of DIBAL-H was enough for the cyclization. The DIBAL-H-promoted transformation could be applied to regio-defined synthesis of unsymmetrically substituted siloles from 4-hydrosilyl-1-silylalk-3-en-1-ynes. This pre-installation
已经开发出一种通过分子内C-Si键形成来制备取代的苯并甲
硅烷基和不对称取代的甲
硅烷基的有效方法。1-甲氧基甲
硅烷基-2- [2-(三甲基甲
硅烷基)
乙炔基]苯与1.5当量的氢化
二异丁基铝(D
IBAL-H)的反应以良好或高收率得到苯并甲
硅烷基。类似地,将4-甲氧基甲
硅烷基-1-甲
硅烷基烷-3-烯-1-炔环化为多取代的甲
硅烷基。对该转变的机理研究发现,甲氧基甲
硅烷基最初是通过D
IBAL-H的作用转化为相应的氢甲
硅烷基,并且所得的氢
硅烷经历了D
IBAL-H促进的环化反应生成苯并甲
硅烷基。当将1-氢甲
硅烷基-2- [2-(三甲基甲
硅烷基)
乙炔基]苯用作底物时,亚
化学计量的D
IBAL-H足以进行环化。D
IBAL-H促进的转化可用于由4-氢甲
硅烷基-1-甲
硅烷基-3-烯-1-炔的不对称取代甲
硅烷的区域定义合成。这种预安装方法可通过完全区域选择直接访问多取代的
硅烷。