Institute of Next Generation Matter Transformation, College of Chemical Engineering at Huaqiao University, 668 Jimei Blvd, Xiamen, Fujian 361021, P. R. China.
Chem Commun (Camb). 2018 Sep 11;54(73):10240-10243. doi: 10.1039/c8cc05390a.
Herein, we report an efficient and practical strategy for the synthesis of five types of imidazo[2,1-a]isoquinolines via Cp*RhIII-catalyzed [4+2] annulation of 2-arylimidazoles and α-diazoketoesters, whose structural and substituted diversity at 5- or 6-position can be precisely controlled by the α-diazoketoester coupling partners. Compared with previous reports, in this study, we merged two attractive C-C cleavage strategies (retro-Claisen and decarboxylation) into the classical C-H functionalization/condensation process by choosing appropriate ester groups (-COOEt, -COOtBu or -COOiPr) or inexpensive additives (HOAc or KOAc). Moreover, the synthetic efficacies of these methods were demonstrated by the concise synthesis of several bioactive compounds and the late-stage modification of representative drugs.
在此，我们报告了一种通过 Cp*RhIII 催化的 2-芳基咪唑和α-重氮酮酯的[4+2]环加成反应高效合成五种类型的咪唑并[2,1-a]异喹啉的实用策略，其 5-或 6-位的结构和取代多样性可以通过α-重氮酮酯偶联伙伴精确控制。与以前的报道相比，在这项研究中，我们通过选择合适的酯基（-COOEt、-COOtBu 或 -COOiPr）或廉价添加剂（HOAc 或 KOAc），将两种有吸引力的 C-C 断裂策略（反-Claisen 和脱羧）合并到经典的 C-H 官能化/缩合过程中。此外，这些方法的合成效果通过几种生物活性化合物的简洁合成和代表性药物的后期修饰得到了证明。
