Asymmetric Catalysis with Silicon-Based Cuprates: Enantio- and Regioselective Allylic Substitution of Linear Precursors
作者:Alexander Hensel、Martin Oestreich
DOI:10.1002/chem.201501371
日期:2015.6.15
linear allylic phosphates that makes use of catalytically generated cuprate‐type silicon nucleophiles is reported. The method relies on soft bis(triorganosilyl) zincs as silicon pronucleophiles that are prepared in situ from the corresponding hard lithium reagents by transmetalation with ZnCl2. With a preformed chiral N‐heterocyclic carbene–copper(I) complex as catalyst, exceedingly high enantiomeric excesses
据报道,利用催化生成的铜酸盐型硅亲核试剂,对线性和烯丙基磷酸的对映体和区域选择性烯丙基甲硅烷基化。该方法依赖于软双(三有机甲硅烷基)锌作为硅原核亲核体,其是通过与相应的硬锂试剂通过用ZnCl 2进行金属转移而原位制备的。用预先形成的手性N-杂环卡宾-铜(I)络合物作为催化剂,可获得极高的对映体过量。新方法优于使用硅硼试剂作为亲核硅来源的现有方法。