Palmer W Neil, Chirik Paul J
Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
ACS Catal. 2017;7(9):5674-5678. doi: 10.1021/acscatal.7b02051. Epub 2017 Jul 28.
Cobalt dialkyl complexes bearing -diimine ligands proved to be active precatalysts for the nondirected, C(sp)-H selective hydrogen isotope exchange (HIE) of alkylarenes using D gas as the deuterium source. Alkylarenes with a variety of substitution patterns and heteroatom substituents on the arene ring were successfully labeled, enabling high levels of incorporation into primary, secondary, and tertiary benzylic C(sp)-H bonds. In some cases, the HIE proceeded with high diastereoselectivity and application of the cobalt-catalyzed method to enantioenriched substrates with benzylic stereocenters provided enantioretentive hydrogen isotope exchange at tertiary carbons.
带有二亚胺配体的钴二烷基配合物被证明是使用D2气体作为氘源的烷基芳烃非定向C(sp3)-H选择性氢同位素交换(HIE)的活性预催化剂。芳烃环上具有各种取代模式和杂原子取代基的烷基芳烃被成功标记,能够高水平地掺入伯、仲和叔苄基C(sp3)-H键中。在某些情况下,HIE以高非对映选择性进行,并且将钴催化方法应用于具有苄基立体中心的对映体富集底物时,在叔碳上提供了对映体保持的氢同位素交换。