Shi Yang, Zhang Luoqiang, Lan Jingbo, Zhang Min, Zhou Fulin, Wei Wenlong, You Jingsong
Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China.
Angew Chem Int Ed Engl. 2018 Jul 16;57(29):9108-9112. doi: 10.1002/anie.201804528. Epub 2018 Jun 19.
By making use of a dual-chelation-assisted strategy, a completely regiocontrolled oxidative C-H/C-H cross-coupling reaction between an N-acylaniline and a benzamide has been accomplished for the first time. This process constitutes a step-economic and highly efficient pathway to 2-amino-2'-carboxybiaryl scaffolds from readily available substrates. A Cp*-free RhCl /TFA catalytic system was developed to replace the [CpRhCl ] /AgSbF system generally used in oxidative C-H/C-H cross-coupling reactions between two (hetero)arenes (Cp=pentamethylcyclopentadienyl, TFA=trifluoroacetic acid). The RhCl /TFA system avoids the use of the expensive Cp* ligand and AgSbF . As an illustrative example, the procedure developed herein greatly streamlines the total synthesis of the naturally occurring benzo[c]phenanthridine alkaloid oxynitidine, which was accomplished in excellent overall yield.
通过采用双螯合辅助策略，首次实现了N-酰基苯胺与苯甲酰胺之间完全区域可控的氧化C-H/C-H交叉偶联反应。该过程为从易得的底物合成2-氨基-2'-羧基联芳基骨架提供了一条步骤经济且高效的途径。开发了一种无Cp的RhCl/TFA催化体系，以取代通常用于两个（杂）芳烃之间氧化C-H/C-H交叉偶联反应的[CpRhCl]/AgSbF体系（Cp* = 五甲基环戊二烯基，TFA = 三氟乙酸）。RhCl/TFA体系避免了使用昂贵的Cp*配体和AgSbF。作为一个示例，本文所开发的方法极大地简化了天然存在的苯并[c]菲啶生物碱氧化苦参碱的全合成，其总产率优异。
