Pyridines are widely used across the chemical sciences in applications ranging from pharmaceuticals, ligands for metal complex and battery technologies. Direct functionalization of pyridine C–H bonds is an important strategy to make useful pyridine derivatives, but there are few ways to selectively transform the 4-position of the scaffold. We recently reported that pyridines can be converted into heterocyclic phosphonium salts that can serve as generic handles for multiple subsequent bond-forming processes. Reactions with nucleophiles and transition-metal cross-couplings will be described to make C–O, C–S, C–N, and C–C bonds in a diverse range of pyridines including those embedded in complex pharmaceuticals. 1 Introduction 2 Direct, Regioselective Functionalization of Pyridines 3 4-Position Selectivity via Metal Catalysis 4 Versatile Functional Groups versus Specific Bond Constructions 5 Phosphonium Salts as Reagents for Pyridine Functionalization 6 Conclusions

中文翻译：

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通过杂环鏻盐的 4-选择性吡啶官能化反应

吡啶广泛应用于化学科学领域，包括制药、金属配合物配体和电池技术。吡啶 C-H 键的直接官能化是制备有用的吡啶衍生物的重要策略，但很少有方法可以选择性地转化支架的 4 位。我们最近报道了吡啶可以转化为杂环鏻盐，可以作为多个后续成键过程的通用处理。将描述与亲核试剂和过渡金属交叉偶联物的反应，以在各种吡啶（包括嵌入复杂药物的吡啶）中生成 C-O、C-S、C-N 和 C-C 键。1 介绍 2 直接，