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
Asymmetric protonation of lithium enolate using 5-substituted pyrrolidin-2-one as a chiral proton source
作者:Hidetaka Fujihara、Kiyoshi Tomioka
DOI:10.1039/a901581g
日期:——
Asymmetric protonation of the lithium enolate moiety of a 2-substituted α-tetralone (3,4-dihydronaphthalen-1(2H)-one) was examined using 5-substituted pyrrolidin-2-ones as chiral proton sources. Among the three types of pyrrolidin-2-ones bearing either a hydroxymethyl group or steric bulk or a chelation site at the 5-position, the pyrrolidin-2-ones bearing steric bulk gave the enantiomerically enriched α-tetralone derivative in up to 72% ee.