School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
Eli Lilly and Company Limited, Erl Wood Manor, Windelesham, Surrey, GU20 6PH, UK.
Angew Chem Int Ed Engl. 2019 Apr 1;58(15):5003-5007. doi: 10.1002/anie.201900510. Epub 2019 Mar 12.
Herein, we report a strategy for the generation of nitrogen-radicals by ground-state single electron transfer with organyl-Ni species. Depending on the philicity of the N-radical, two types of processes have been developed. In the case of nucleophilic aminyl radicals direct N-arylation with aryl organozinc, organoboron, and organosilicon reagents was achieved. In the case of electrophilic amidyl radicals, cascade processes involving intramolecular cyclization, followed by reaction with both aryl and alkyl organometallics have been developed. The N-cyclization-alkylation cascade introduces a novel retrosynthetic disconnection for the assembly of substituted lactams and pyrrolidines with its potential demonstrated in the short total synthesis of four venom alkaloids.
在此,我们报告了一种通过有机镍物种的基态单电子转移生成氮自由基的策略。根据 N-自由基的亲核性,开发了两种类型的反应。对于亲核的氨酰基自由基,可与芳基有机锌、有机硼和有机硅试剂直接进行 N-芳基化。对于亲电的酰氨基自由基,通过分子内环化,然后与芳基和烷基有机金属试剂反应的级联反应已经被开发出来。N-环化-烷基化级联反应为取代的内酰胺和吡咯烷的组装引入了一种新的逆合成切断,其在四个毒液生物碱的短全合成中得到了证明。