A mechanistically distinctive copper-catalyzed radical annulation to valuable 2-(trifluoromethyl)pyrazolo[1,5-a]pyridines and their benzo analogues has been described for the first time. Notably, the newly developed complementary process allows the synthesis of 4- or 6-substituted target molecular entities as a single product, which was previously challenging to access by existing methods. The utility of this process is further demonstrated by the facile construction of four different ring systems, a gram-scale synthesis, and the late-stage functionalization of bioactive molecules.

中文翻译：

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通过铜 (I) 催化自由基环化对 2-(三氟甲基) 吡唑并[1,5-a] 吡啶及其苯并类似物进行模块化访问

首次描述了一种机制独特的铜催化自由基环化对有价值的 2-(三氟甲基)吡唑并[1,5- a ] 吡啶及其苯并类似物的反应。值得注意的是，新开发的补充工艺允许将 4 或 6 取代的目标分子实体作为单一产品合成，这在以前很难通过现有方法获得。该过程的实用性通过四种不同环系统的简易构建、克级合成和生物活性分子的后期功能化得到进一步证明。