Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA.
Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, OR, 97331 2145, USA.
Angew Chem Int Ed Engl. 2021 Aug 9;60(33):17925-17931. doi: 10.1002/anie.202105354. Epub 2021 Jul 14.
Single-electron N-heterocyclic carbene (NHC) catalysis has gained attention recently for the synthesis of C-C bonds. Guided by density functional theory and mechanistic analyses, we report the light-driven synthesis of aliphatic and α-amino ketones using single-electron NHC operators. Computational and experimental results reveal that the reactivity of the key radical intermediate is substrate-dependent and can be modulated through steric and electronic parameters of the NHC. Catalyst potential is harnessed in the visible-light driven generation of an acyl azolium radical species that undergoes selective coupling with various radical partners to afford diverse ketone products. This methodology is showcased in the direct late-stage functionalization of amino acids and pharmaceutical compounds, highlighting the utility of single-electron NHC operators.
单电子 N-杂环卡宾（NHC）催化因其在 C-C 键合成方面的应用而受到关注。本研究受密度泛函理论和机理分析的指导，报道了利用单电子 NHC 催化剂进行脂肪族和α-氨基酮的光驱动合成。计算和实验结果表明，关键自由基中间体的反应性取决于底物，并可通过 NHC 的空间和电子参数进行调节。本研究利用催化剂电势在可见光驱动下生成酰基氮宾自由基物种，该物种选择性地与各种自由基偶联，得到各种酮产物。该方法在氨基酸和药物化合物的直接后期官能化中得到了展示，突出了单电子 NHC 催化剂的实用性。
