Enantioselective Construction of Quaternary Stereogenic Carbon Atoms by the Lewis Base Catalyzed Additions of Silyl Ketene Imines to Aldehydes
作者:Scott E. Denmark、Tyler W. Wilson、Matthew T. Burk
DOI:10.1002/chem.201403342
日期:2014.7.21
the aldol addition reaction. In the presence of SiCl4 and the catalytic action of a chiral phosphoramide, silyl ketene imines undergo extremely rapid and high yielding addition to a wide variety of aromatic aldehydes with excellent diastereo‐ and enantioselectivity. Of particular note are the high yields and selectivities obtained from electron‐rich, electron‐poor, and hindered aldehydes. Linear aliphatic
衍生自多种α-支化腈的甲硅烷基烯酮亚胺已被开发为通过醛醇加成反应构建季立体异构中心的高度有用的试剂。在SiCl 4的存在和手性磷酰胺的催化作用下,甲硅烷基烯酮亚胺会以极快的非对映选择性和对映选择性快速,高收率地添加到各种芳香醛中。特别值得注意的是从富电子,贫电子和受阻醛获得的高收率和选择性。直链脂肪族醛确实具有良好的diastereo-和对映选择性的存在下反应Ñ卜4 Ñ +我-,但支链醛的反应性低得多。半经验计算通过开放的过渡态为观察到的非对映和对映选择性提供了合理的条件。