Triaryl Carbonium Ion-Pair-Mediated Cooperative Aerobic Dehydrogenation of N-Heterocycles

IF 11.3 1区化学 Q1 CHEMISTRY, PHYSICAL

ACS Catalysis Pub Date : 2022-11-03 DOI:10.1021/acscatal.2c04010

Zhenguo Zhang, Jun Gu, Liang Ji, Xiaoxiao Liu, Ting Zhang, Yongheng Lv, Fang Liu*, Zhenhua Jia* and Teck-Peng Loh*,

引用次数: 3

Abstract

The triphenylmethyl radical was discovered by Gomberg in 1900 and has been shown to be a persistent radical species. Surprisingly, this radical is rarely used in organic synthesis since its discovery over a century ago. Here, we report a metal-free aerobic dehydrogenation of N-heterocycles mediated by a triphenylmethyl radical generated from a triaryl carbonium ion pair as the precatalyst in the presence of TEMPO. This protocol exhibits a broad substrate scope and excellent functional group tolerance. The practicality has also been demonstrated with the gram-scale preparation of key intermediates of small-molecule drugs and late-stage functionalization of various dipine drugs. Mechanistic studies and DFT calculations revealed that the triphenylmethyl radical was involved in the catalytic cycle and was essential for the aerobic dehydrogenation process.

Abstract Image

查看原文本刊更多论文

三芳基碳离子对介导N-杂环的协同好氧脱氢

三苯基甲基自由基于1900年由Gomberg发现，并已被证明是一种持久性自由基。令人惊讶的是，自从一个多世纪前这种自由基被发现以来，很少在有机合成中使用。本文报道了在TEMPO存在下，由三芳基碳离子对生成的三苯基甲基自由基作为预催化剂介导的n -杂环的无金属有氧脱氢反应。该方案具有广泛的底物范围和良好的官能团耐受性。小分子药物关键中间体的克级制备和各种地平药物的后期功能化也证明了其实用性。机理研究和DFT计算表明，三苯基甲基自由基参与了催化循环，对好氧脱氢过程至关重要。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

ACS Catalysis CHEMISTRY, PHYSICAL-

CiteScore

20.80

自引率

6.20%

发文量

1253

审稿时长

1.5 months

期刊介绍： ACS Catalysis is an esteemed journal that publishes original research in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. It offers broad coverage across diverse areas such as life sciences, organometallics and synthesis, photochemistry and electrochemistry, drug discovery and synthesis, materials science, environmental protection, polymer discovery and synthesis, and energy and fuels. The scope of the journal is to showcase innovative work in various aspects of catalysis. This includes new reactions and novel synthetic approaches utilizing known catalysts, the discovery or modification of new catalysts, elucidation of catalytic mechanisms through cutting-edge investigations, practical enhancements of existing processes, as well as conceptual advances in the field. Contributions to ACS Catalysis can encompass both experimental and theoretical research focused on catalytic molecules, macromolecules, and materials that exhibit catalytic turnover.