Enantioselective One-Pot Catalytic Synthesis of 4,5-Epoxy-3-alkanols and 1-Phenyl-2,3-epoxy-1-alkanols from α,β-Unsaturated Aldehydes
作者:Rebeca Infante、Yulan Hernández、Javier Nieto、Celia Andrés
DOI:10.1002/ejoc.201300397
日期:2013.8
Conformationally restricted perhydrobenzoxazines have been demonstrated to be good chiral ligands for one-pot asymmetric ethylation/epoxidation, and the unprecedented arylation/epoxidation of trisubstituted α,β-unsaturated aldehydes. The scope of the reaction has been studied and a wide set of substrates with allylic strain of different nature has been explored, obtaining good or total diastereoselectivities
构象受限的全氢苯并恶嗪已被证明是用于一锅不对称乙基化/环氧化和三取代 α,β-不饱和醛的前所未有的芳基化/环氧化的良好手性配体。已经研究了反应的范围,并探索了具有不同性质的烯丙基应变的广泛底物,在所有情况下都获得了良好的或完全的非对映选择性。乙基化/环氧化反应的对映控制良好或高,而芳基化/环氧化反应保持中等或良好水平。该反应对于三取代的烯醛是通用的,并且在不饱和醛的 α- 和 β- 位都可以容忍烷基和芳族取代基;然而,双取代的烯醛仍然是具有挑战性的底物。当比较一锅和两锅协议时,