Chiral phosphine oxide BINAPO as a Lewis base catalyst for asymmetric allylation and aldol reaction of trichlorosilyl compounds
作者:Shunsuke Kotani、Shunichi Hashimoto、Makoto Nakajima
DOI:10.1016/j.tet.2007.02.014
日期:2007.4
Chiral phosphine oxide BINAPO, which was readily prepared from chiral phosphine BINAP, exhibited good catalytic activities in the reaction of trichlorosilyl compounds via hypervalent silicate intermediates. The allylation of aldehydes with allyltrichlorosilanes in the presence of a catalytic amount of BINAPO gave the allylated adducts in good enantioselectivities (up to 79% ee) wherein a combination
由手性膦BINAP容易制备的手性膦氧化物BINAPO在三氯甲硅烷基化合物通过高价硅酸盐中间体的反应中表现出良好的催化活性。在催化量的BINAPO存在下,醛与烯丙基三氯硅烷的烯丙基化反应使烯丙基化的加合物具有良好的对映选择性(最高79%ee),其中二异丙基乙胺和四丁基碘化铵作为添加剂的组合对于加速催化循环至关重要。31氧化膦的1 P NMR分析表明,胺促进了氧化膦从硅原子上的解离。BINAPO还促进了二异丙基乙胺作为添加剂存在下醛与三氯甲硅烷基烯醇醚的对映体选择性醛醇缩合反应,从而以高非对映体和对映体选择性(最高syn / anti = 1 / 25,96%ee(anti))提供了相应的醛醇加合物。)。