作者:Songsong Guo、Pei Dong、Yushuang Chen、Xiaoming Feng、Xiaohua Liu
DOI:10.1002/anie.201810679
日期:2018.12.17
copper(I) catalyst for the asymmetric azide‐alkynecycloaddition/[2+2] cascade reaction. Optically active spiroazetidinimine oxindoles were constructed by trapping the ketenimine species under mild reaction conditions. High level of enantioinduction and excellent isolated yields were achieved in the three‐component reaction of various isatin‐derived ketimines, sulfonyl azides, and terminal alkynes. Control
Cu(I)-Catalyzed Asymmetric Mannich Reaction of Glycine Schiff Bases to Ketimines
作者:Ying Fan、Jian Lu、Feng Sha、Qiong Li、Xin-Yan Wu
DOI:10.1021/acs.joc.9b01566
日期:2019.9.20
A copper-catalyzed asymmetric Mannichreaction between glycine Schiff bases and ketimines has been developed. This method afforded 2-oxindole-based chiral syn-α,β-diamino acid derivatives in high yields (89–99%) with good to excellent diastereoselectivities (≤98:2 dr) and excellent enantioselectivities (95–99% ee).
A highly stereoselective Mannichreaction of α-aminoacid derived azlactones with isatin-derived ketimines enabled by a chiral bifunctional squaramide organocatalyst is reported, affording α,β-diamino acid derivatives bearing vicinal quaternary stereocenters in moderate to good yields (40-95%), moderate to excellent diastereoselectivities (3:1 → 20:1), and good to excellent enantioselectivities (66-97%)
Catalytic Asymmetric Synthesis of Vicinal Tetrasubstituted Diamines via Umpolung Cross-Mannich Reaction of Cyclic Ketimines
作者:Wen-Run Zhu、Kai Liu、Jiang Weng、Wei-Hua Huang、Wei-Jie Huang、Qing Chen、Ning Lin、Gui Lu
DOI:10.1021/acs.orglett.0c01578
日期:2020.7.2
A catalytic asymmetric umpolung cross-Mannich reaction of cyclic ketimines is realized. This protocol provides an efficient methodology for the facile synthesis of chiral vicinaltetrasubstituted diamines in high yields with excellent chemo-, regio-, diastereo-, and enantioselectivities using cinchona-derived bifunctional organocatalysts (85–98% yield, up to >20:1 dr, and >99% ee).
Copper-catalyzed enantioselective addition of alcohols to isatin-derived ketimines
作者:Jian Lu、Feng Sha、Xin-Yan Wu
DOI:10.1016/j.tetlet.2019.03.049
日期:2019.4
The first copper-catalyzed enantioselectiveaddition of alcohols to imines was described. In the presence of 1 mol% Cu(OAc)2 complexed with chiral cyclohexane-based N,P-ligand L4, chiral isatin-derived N,O-aminals were obtained in excellent yields (93–99%) and good-to-excellent enantioselectivities (up to 93% ee) under mild conditions.