Enantioselective Michael addition of malonates to α,β-unsaturated ketones catalyzed by rare-earth metal amides RE[N(SiMe3)2]3 with phenoxy-functionalized amino alcohol proligands
Baozhen Yang, Longkang Yang, Chengrong Lu, Bei Zhao, Yizhe Huang
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引用次数: 0
Abstract
A combination of rare-earth metal amides RE[N(SiMe3)2]3 and chiral phenoxy-functionalized amino alcohol proligands was developed to realize the enantioselective Michael addition of malonates with unsaturated ketones. The reactions catalyzed by samarium amide Sm[N(SiMe3)2]3 were performed best together with the chiral proligand H3L1 (H3L1 = 2,4-di-tert-butyl-6-((((1S,2R)-2-hydroxy-1,2-diphenylethyl) amino)methyl)phenol) in DCE with good group tolerance, mostly in high to excellent yields (85–98 %) and good to excellent ee values (50− >99 %). The possible mechanism was also proposed.
期刊介绍:
Tetrahedron Letters provides maximum dissemination of outstanding developments in organic chemistry. The journal is published weekly and covers developments in techniques, structures, methods and conclusions in experimental and theoretical organic chemistry. Rapid publication of timely and significant research results enables researchers from all over the world to transmit quickly their new contributions to large, international audiences.