Asymmetric Syntheses of New Functionalized <i>β</i>-Amino Alcohols via Diastereoselective Addition of Organometallic Reagents onto Oxazolidines
作者:Claude Agami、Sébastien Comesse、Catherine Kadouri-Puchot
DOI:10.1021/jo010779a
日期:2002.3.1
Diastereoselective reactions between (S)-phenylglycinol-derived oxazolidines and two unsaturated organolithium reagents afforded chiral beta-amino alcohols having vinyl and alkynylsilane moieties. When the same reactions were performed in the presence of titanium isopropoxide, a dramatic change of regioselectivity was observed, from the alpha- to the gamma-position, thus producing beta-amino alcohols
(S)-苯基甘醇衍生的恶唑烷与两种不饱和有机锂试剂之间的非对映选择性反应提供了具有乙烯基和炔基硅烷部分的手性β-氨基醇。当在异丙醇钛存在下进行相同的反应时,观察到区域选择性从α-到γ-位置的剧烈变化,从而产生具有烯丙基或烯丙基硅烷官能团的β-氨基醇。建议对每种情况合理化观察到的非对映选择性。