Department of Chemistry, Stanford University, Stanford, CA, 94305-5080, USA.
Angew Chem Int Ed Engl. 2017 Feb 20;56(9):2440-2444. doi: 10.1002/anie.201607845. Epub 2017 Jan 23.
Herein, we report a Zn-ProPhenol catalyzed aza-Darzens reaction using chlorinated aromatic ketones as nucleophilic partners for the efficient and enantioselective construction of complex trisubstituted aziridines. The α-chloro-β-aminoketone intermediates featuring a chlorinated tetrasubstituted stereocenter can be isolated in high yields and selectivities for further derivatization. Alternatively, they can be directly transformed to the corresponding aziridines in a one-pot fashion. Of note, the reaction can be run on gram-scale with low catalyst loading without impacting its efficiency. Moreover, this methodology was extended to α-bromoketones which are scarcely used in enantioselective catalysis because of their sensitivity and lack of accessibility.
在这里，我们报告了一种由 Zn-ProPhenol 催化的氮杂-Darzens 反应，使用氯化芳香酮作为亲核试剂，高效和对映选择性地构建复杂的三取代氮丙啶。具有氯化四取代立体中心的α-氯-β-氨基酮中间体可以高产率和高选择性地分离出来，用于进一步衍生化。或者，它们可以在一锅法中直接转化为相应的氮丙啶。值得注意的是，即使在低催化剂负载量下，反应也可以在克级规模上进行，而不会影响其效率。此外，该方法还扩展到了α-溴代酮，由于其敏感性和不易获得性，α-溴代酮在对映选择性催化中很少使用。
