Pyridine is an important structural motif that is prevalent in natural products, drugs, and materials. Methods that functionalize and derivatize pyridines have gained significant attention. Recently, a large number of transition-metal-free reactions have been developed. In this review, we provide a brief summary of recent advances in transition-metal-free functionalization and derivatization reactions of pyridines, categorized according to their reaction modes. 1 Introduction 2 Metalated Pyridines as Nucleophiles 2.1 Deprotonation 2.2 Halogen–Metal exchange 3 Activated Pyridines as Electrophiles 3.1 Asymmetric 2-Allylation by Chiral Phosphite Catalysis 3.2 Activation of Pyridines by a Bifunctional Activating Group 3.3 Alkylation of Pyridines by 1,2-Migration 3.4 Alkylation of Pyridines by [3+2] Addition 3.5 Pyridine Derivatization by Catalytic In Situ Activation Strategies 3.6 Reactions via Heterocyclic Phosphonium Salts 4 Radical Reactions for Pyridine Functionalization 4.1 Pyridine Functionalization through Radical Addition Reactions 4.2 Pyridine Functionalization through Radical–Radical Coupling Reactions 5 Derivatization of Pyridines through the Formation of Meisenheimer-Type Pyridyl Anions 6 Conclusion

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吡啶的无过渡金属官能化和衍生化反应的最新进展

吡啶是一种重要的结构基序，广泛存在于天然产物、药物和材料中。使吡啶官能化和衍生化的方法受到了极大的关注。最近，已经开发了大量无过渡金属的反应。在这篇综述中，我们简要总结了吡啶的无过渡金属官能化和衍生化反应的最新进展，根据反应模式进行分类。1 引言 2 作为亲核试剂的金属化吡啶 2.1 去质子化 2.2 卤素-金属交换 3 作为亲电试剂的活化吡啶 3.1 手性亚磷酸酯催化的不对称 2-烯丙基化 3.2 双功能激活基团对吡啶的激活 3.3 吡啶的烷基化 3.3 烷基化 3.3 吡啶的烷基化吡啶由 [3+2] 加成 3。