Conjugate Addition of 2- and 4-Pyridylcuprates: An Expeditious Asymmetric Synthesis of Natural (−)-Evoninic Acid
作者:Alan C. Spivey、Lena Shukla、Judy F. Hayler
DOI:10.1021/ol070011y
日期:2007.3.1
of 2-bromo-3-methylpyridine to (E)-methyl crotonate then diastereoselective enolate alkylation and lipase-mediated enantioselective ester hydrolysis have enabled an efficient four-step first asymmetric synthesis of the Celastraceae sesquiterpenoid esterifying ligand (-)-(1'S,2'S)-evoninic acid.
[反应:见正文]描绘了将2-和第一个4-吡啶基吉尔曼同价物共轭添加到各种α,β-不饱和迈克尔受体上的范围和限制。将2-溴-3-甲基吡啶的铜酸盐共轭添加到(E)-巴豆酸甲酯中,然后进行非对映选择性烯酸酯烷基化和脂肪酶介导的对映选择性酯水解,使得高效的四步第一步不对称合成Celastraceae倍半萜酸酯化配体(- )-(1'S,2'S)-戊酸。