Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA.
J Am Chem Soc. 2012 Feb 1;134(4):2036-9. doi: 10.1021/ja211600g. Epub 2012 Jan 23.
A highly selective C-H amination reaction under iron catalysis has been developed. This novel system, which employs an inexpensive, nontoxic [Fe(III)Pc] catalyst (typically used as an industrial ink additive), displays a strong preference for allylic C-H amination over aziridination and all other C-H bond types (i.e., allylic > benzylic > ethereal > 3° > 2° ≫ 1°). Moreover, in polyolefinic substrates, the site selectivity can be controlled by the electronic and steric character of the allylic C-H bond. Although this reaction is shown to proceed via a stepwise mechanism, the stereoretentive nature of C-H amination for 3° aliphatic C-H bonds suggests a very rapid radical rebound step.
已开发出一种在铁催化下高度选择性的 C-H 氨化反应。该新型体系采用廉价、无毒的[Fe(III)Pc]催化剂（通常用作工业油墨添加剂），对烯丙基 C-H 氨化具有强烈的选择性，而对氮丙啶化和所有其他 C-H 键类型（即烯丙基>苄基>醚基>3°>2°>1°）的选择性较低。此外，在多烯烃底物中，烯丙基 C-H 键的电子和空间位阻特性可以控制反应的位点选择性。尽管该反应被证明是通过逐步机制进行的，但 3°脂肪族 C-H 键的 C-H 氨化的立体保留性质表明存在非常快速的自由基回弹步骤。
