Enantioselective Synthesis of α-Stereogenic γ-Keto Esters via Formal Umpolung
作者:G. K. Surya Prakash、Fang Wang、Zhe Zhang、Chuanfa Ni、Ralf Haiges、George A. Olah
DOI:10.1021/ol301112m
日期:2012.7.6
feasible method has been developed for the enantioselective synthesis of α-stereogenic γ-keto esters. By employing nitro(phenylsulfonyl)methane as an acyl anion equivalent, the integrated Michael addition reaction-oxidative methanolysis protocol allows the preparation of various γ-keto esters with high optical purities.
Highly Enantioselective Intermolecular Stetter Reaction of Simple Acrylates: Synthesis of α-Chiral γ-Ketoesters
作者:Nathalie E. Wurz、Constantin G. Daniliuc、Frank Glorius
DOI:10.1002/chem.201202432
日期:2012.12.14
Simple Stetter: A novel N‐heterocyclic carbene (NHC) was designed by combining an electron‐rich 2,6‐dimethoxy substituent and an underestimated yet promising chiral motif. With this NHC in hand, a highlyenantioselectiveintermolecularStetterreaction of simple acrylates was developed, yielding versatile α‐chiral γ‐ketoesters. This represents the first catalytic asymmetric route towards these valuable