Highlyπ-Facial Stereoselective Aldol Reaction of (S)-Proline-Derived Amide Enolate with Benzaldehydes
作者:Waldemar Adam、Aimin Zhang
DOI:10.1002/ejoc.200390097
日期:2003.2
The asymmetric aldol reaction of the (S)-proline-derived bicyclic amide enolate 1 with benzaldehydes selectively affords the two diastereomeric aldol adducts (3S,3′R,8S)-3a and (3S,3′S,8S)-3a, of four possible diastereomers, in good yield. The high control of π-facial stereoselectivity at the endocyclic C-3 stereocenter is due to perfect shielding by the pseudo-axial phenyl ring at the C-1 position
(S)-脯氨酸衍生的双环酰胺烯醇化物 1 与苯甲醛的不对称醛醇反应选择性地提供了两种非对映异构醛醇加合物 (3S,3'R,8S)-3a 和 (3S,3'S,8S)-3a,四种可能的非对映异构体,收率良好。内环 C-3 立体中心的 π 面立体选择性的高度控制是由于 C-1 位置的假轴苯环的完美屏蔽。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)