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为突破经典Catellani反应中五元钯杂环的限制，发展了一种新型的钯/降冰片烯协同催化体系，通过“一锅法”实现咪唑并[1,2-a]吡啶与2-溴苯甲酸的C—H/C—H [3+2]环化与C—H芳基化串联反应，高效构建了具有良好官能团耐受性的多环咪唑并[1,2-a]吡啶骨架。在该策略中，2-溴苯甲酸作为双功能试剂，同步实现了三个C—H位点的官能团化。机理研究揭示，反应经历了一个六元碳芳基-降冰片烯钯杂环(C—ANP)中间体，该发现突破了经典Catellani反应中五元钯杂环的关键限制。
Abstract：To overcome the limitation of five-membered palladacycle in the classical Catellani reaction, this paper develops a novel palladium/norbornene cooperative catalytic system. Via a one-pot procedure, this system realizes the tandem C—H/C—H [3+2] annulation and C—H arylation reaction between imidazo[1,2-a]pyridines and 2-bromobenzoic acid, efficiently constructing a series of polycyclic imidazo[1,2-a]pyridine skeletons with good functional group tolerance. In this strategy, 2-bromobenzoic acid acts as a dual-function reagent, enabling the simultaneous functionalization of three C—H sites. Mechanistic studies reveal that the reaction proceeds through a six-membered carbon aryl-norbornene palladacycle(C—ANP) intermediate.
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基本信息:
中图分类号:O621.251
引用信息:
[1]闫强,刘石磊,南江.钯/降冰片烯催化的C—H环化/芳基化串联反应研究[J].陕西理工大学学报(自然科学版),2026,42(01):11-19.
基金信息:
国家自然科学基金项目(22171171); 陕西省青年科技新星项目(2022KJXX-15); 陕西省科协人才托举项目(20200605)
2026-02-11
2026-02-11