School of Chemistry, Norwich Research Park, University of East Anglia, Norwich, NR4 7TJ, UK.
Department of Medicinal Chemistry, GlaxoSmithKline, Gunnels Wood Road, Stevenage, Hertfordshire, UK.
Angew Chem Int Ed Engl. 2017 May 2;56(19):5322-5326. doi: 10.1002/anie.201611990. Epub 2017 Apr 5.
We report a multi-component asymmetric Brønsted acid-catalyzed aza-Darzens reaction which is not limited to specific aromatic or heterocyclic aldehydes. Incorporating alkyl diazoacetates and, important for high ee's, ortho-tert-butoxyaniline our optimized reaction (i.e. solvent, temperature and catalyst study) affords excellent yields (61-98 %) and mostly >90 % optically active cis-aziridines. (+)-Chloramphenicol was generated in 4 steps from commercial starting materials. A tentative mechanism is outlined.
我们报告了一种多组分不对称的 Brønsted 酸催化的氮杂-Darzens 反应,该反应不受特定芳香族或杂环醛的限制。我们的优化反应(即溶剂、温度和催化剂研究)中引入了烷基重氮乙酸酯和对叔丁氧基苯胺,这对于获得高对映选择性至关重要,可得到优异的产率(61-98%)和大部分大于 90%的光学活性顺式氮丙啶。(+)-氯霉素可以从商业起始原料经 4 步反应制得。提出了一个可能的反应机理。