Palladium‐Catalyzed Asymmetric Decarboxylative Allylation of Azlactone Enol Carbonates: Fast Access to Enantioenriched α‐Allyl Quaternary Amino Acids
作者:Massimo Serra、Eric Bernardi、Giorgio Marrubini、Ersilia De Lorenzi、Lino Colombo
DOI:10.1002/ejoc.201801363
日期:2019.1.31
A practical synthetic protocol for the preparation of enantioenriched 4‐allyl oxazol‐5‐ones was developed. The key Pd‐catalyzed decarboxylative allylation allowed the attainment of the allylated derivatives in very good yields (83–98 %) and with ee up to 85 %. The corresponding quaternary amino acids can be recovered in their enantiopure form or in high optical purity after a single recrystallization
开发了一种实用的合成方案,用于制备对映体富集的4-烯丙基恶唑5-酮。关键的钯催化脱羧烯丙基化使烯丙基化衍生物的收率很高(83-98%),而ee最高可达85%。在单个重结晶步骤后,可以其对映体纯形式或高光学纯度回收相应的季氨基酸。