Roy and Diana Vagelos Laboratories, Department of Chemistry , University of Pennsylvania , 231 South 34th Street , Philadelphia , Pennsylvania 19104-6323 , United States.
Department of Chemistry , Virginia Commonwealth University , 1001 West Main Street , P.O. Box 842006, Richmond , Virginia 23284-9069 , United States.
Org Lett. 2019 Apr 5;21(7):2317-2321. doi: 10.1021/acs.orglett.9b00602. Epub 2019 Mar 12.
Photoredox-mediated radical/polar crossover (RPC) processes offer new avenues for the synthesis of cyclic molecules. This process has been realized for the construction of medium-sized saturated nitrogen heterocycles. Photocatalytically generated alkyl radicals possessing pendant leaving groups engage imines in C-C bond formation, and subsequent reduction of the intermediate nitrogen-centered radical triggers anionic ring closure. With the aid of visible light irradiation, substituted pyrrolidines, piperidines, and azepanes can be prepared under mild, redox-neutral conditions.
光氧化还原介导的自由基/极性交叉（RPC）过程为环状分子的合成提供了新途径。该过程已应用于构建中等大小的饱和氮杂环。具有侧链离去基团的光催化生成的烷基自由基与亚胺发生 C-C 键形成反应，随后中间氮中心自由基的还原引发阴离子环闭合。在可见光照射下，在温和、氧化还原中性条件下可以制备取代的吡咯烷、哌啶和氮杂环庚烷。
