The initial discovery and establishment of a family of novel iridium catalysts possessing N-heterocyclic carbene units alongside bulky phosphine ligands allowed selected substrates to be labelled using deuterium or tritium gas at desirably low catalyst loadings via an ortho-directed C-H insertion process. Such a method has broad applicability and offers distinct advantages within the pharmaceutical industry, directly facilitating the ability to carefully monitor a potential drug molecule's biological fate. Over the past decade since these initial protocols were divulged, many additional advances have been made in terms of catalyst design and substrate scope. This review describes the broadened array of new iridium catalysts and associated protocols for direct and selective C-H activation and hydrogen isotope insertion within a number of new chemical entities of direct relevance to the pharmaceutical industry.

中文翻译：

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铱(I)催化定向氢同位素交换的最新进展


最初发现和建立了一系列具有 N-杂环卡宾单元和大体积膦配体的新型铱催化剂，允许使用氘气或氚气以所需的低催化剂负载量通过邻位引导的 CH 插入过程来标记选定的底物。这种方法具有广泛的适用性，并在制药行业中提供了独特的优势，直接促进了仔细监测潜在药物分子的生物命运的能力。自这些最初的协议公布以来的过去十年中，在催化剂设计和底物范围方面取得了许多额外的进展。本综述描述了一系列扩大的新型铱催化剂以及用于直接和选择性 CH 活化以及氢同位素插入到与制药行业直接相关的许多新化学实体中的相关方案。