Enantioselective Synthesis of 4-Hydroxytetrahydropyridine Derivatives by Intramolecular Addition of Tertiary Enamides to Aldehydes
作者:Shuo Tong、De-Xian Wang、Liang Zhao、Jieping Zhu、Mei-Xiang Wang
DOI:10.1002/anie.201200459
日期:2012.4.27
Stable tertiaryenamides and enecarbamates undergo highly enantioselectiveintramolecular nucleophilic addition to aldehyde units catalyzed by chiral binol–Ti complexes under mild conditions to produce the title compounds in up to 99.5 % or greater enantiomeric excess. A positive nonlinear effect was detected and the formation of binol–Ti aggregates suggests an intricate asymmetric catalytic pathway