Catalytic Asymmetric Ring-Opening of meso-Aziridines with Malonates under Heterodinuclear Rare Earth Metal Schiff Base Catalysis

Catalytic asymmetric ring-opening of meso-aziridines with malonates is described. The combined use of two rare earth metal sources with different properties promoted the desired ring-opening reaction. A 1:1:1 mixture of a heterobimetallic La(O-iPr)3/Yb(OTf)3/Schiff base 1a (0.25−10 mol %) efficiently promoted the reaction of five-, six-, and seven-membered ring cyclic meso-aziridines as well as acyclic meso-aziridines with dimethyl, diethyl, and dibenzyl malonates, giving chiral cyclic and acyclic γ-amino esters in 99−63% yield and >99.5−97% ee.

本文报道了丙二酸酯类与内消旋氮丙环（meso-aziridines）的催化不对称开环反应。采用两种性能各异的稀土金属源联用，可促进该目标开环反应。由异双金属体系异丙氧基镧(La(O-iPr)3)/三氟甲磺酸镱(Yb(OTf)3)/希夫碱1a（0.25−10 mol%）按1:1:1比例混合得到的催化体系，可高效催化五元、六元及七元环状内消旋氮丙环与非环状内消旋氮丙环，分别与丙二酸二甲酯、丙二酸二乙酯及丙二酸二苄酯发生反应，以63%~99%的收率和97%~>99.5%的对映体过量值（enantiomeric excess, ee）得到手性环状及非环状γ-氨基酯类产物。