作者:Luca Deiana、Pawel Dziedzic、Gui‐Ling Zhao、Jan Vesely、Ismail Ibrahem、Ramon Rios、Junliang Sun、Armando Córdova
DOI:10.1002/chem.201100042
日期:2011.7.4
highly enantioselective one‐pot cascade sequence based on the combination of asymmetric amine and N‐heterocyclic carbene catalysis (AHCC) is also disclosed. This one‐pot three‐component co‐catalytic transformation between α,β‐unsaturated aldehydes, hydroxylamine derivatives, and alcohols gives the corresponding N‐tert‐butoxycarbonyl and N‐carbobenzyloxy‐protected β‐amino acid esters with ee values ranging
介绍了α,β-不饱和醛高度对映选择性有机催化叠氮化的发展,范围和应用。α,β-不饱和醛的氨基催化叠氮化使β-甲酰基氮丙啶的不对称形成率高达> 19:1 dr和99% ee。α-单取代的烯醛的氨基催化叠氮化可以高产率和高达99%ee的速率接近末端α-取代-α-甲酰基氮丙啶 。对于双取代的α,β-不饱和醛的有机催化叠氮化,转化具有很高的非对映选择性和对映选择性,并得到几乎对映体纯的β-甲酰基官能化氮丙啶产品(99% ee)。还公开了基于不对称胺和N-杂环卡宾催化(AHCC)结合的高度对映选择性单锅级联序列。α,β不饱和醛,羟胺衍生物,和醇之间这种一锅三组分共催化转化得到相应的Ñ -叔丁氧羰基和ñ -苄酯基保护的β氨基酸酯与EE值范围从92- 99%。还讨论了所有这些催化转化的机理和立体化学。