Preparation of <i>syn</i>-δ-Hydroxy-β-amino Esters via an Intramolecular Hydrogen Bond Directed Diastereoselective Hydrogenation. Total Synthesis of (3<i>S</i>,4a<i>S</i>,6<i>R</i>,8<i>S</i>)-Hyperaspine
作者:Wei Zhu、Dawei Ma
DOI:10.1021/ol036097m
日期:2003.12.1
Hydrogenation of delta-hydroxy-beta-ketoester-derived enamines 8 produces syn-delta-hydroxy-beta-amino esters 9 diastereoselectively, which may be directed by the formation of an intramolecularhydrogenbond between the delta-hydroxyl and beta-amino groups. By using this method and a Dieckmann reaction as the key steps, (3S,4aS,6R,8S)-hyperaspine, a new type of ladybird alkaloid, is synthesized. [reaction: