Highly Diastereo- and Enantioselective Synthesis of α-Spiro-δ-lactams by an Organocascade Reaction
作者:Kaiheng Zhang、Marta Meazza、Vojtěch Dočekal、Mark E. Light、Jan Veselý、Ramon Rios
DOI:10.1002/ejoc.201700193
日期:2017.4.3
An asymmetric synthesis of α-spiro-δ-lactam via organocascade reaction from easily accessible starting materials is reported. The catalytic sequence undergoes enantioselective Michael addition of β-ketoamide to α,β-unsaturated aldehyde catalysed by a secondary amine catalyst, followed by hemiaminal annulation. Optically enantiopure compounds with two contiguous stereogenic centres are obtained in good
报道了通过有机级联反应从容易获得的起始材料不对称合成 α-螺-δ-内酰胺。催化序列在仲胺催化剂的催化下,对 β-酮酰胺与 α,β-不饱和醛进行对映选择性迈克尔加成,然后进行半胺化环化。以良好的产率和出色的选择性(高达 >20:1 dr 和高达 >99% ee)获得具有两个连续立体中心的光学对映体纯化合物。