Dündar Esra, Işık Murat, Yildirim Erol, Tanyeli Cihangir
Department of Chemistry, Middle East Technical University, 06800 Ankara, Türkiye.
Department of Food Engineering, Bingöl University, 12000 Bingöl, Türkiye.
ACS Omega. 2025 Jan 1;10(1):1226-1236. doi: 10.1021/acsomega.4c08792. eCollection 2025 Jan 14.
This work describes the development of the first enantioselective addition reaction between 1,3,5,7-tetramethyl-BODIPYs and isatin derivatives. The reaction utilizes bifunctional quinine/squaramide organocatalysts and affords nine novel chiral BODIPY dyes under mild conditions, with enantioselectivities reaching up to 60%. The synthesized BODIPY-oxindoles exhibit high fluorescence emissions, consistent with their parent BODIPYs, and display tunable colors. A representative example demonstrates a remarkably high quantum yield of 0.78 compared to fluorescein. Notably, the newly created carbon-stereocenter on the isatin skeleton induces detectable asymmetry in the electronically decoupled BODIPY chromophore. This is confirmed by the presence of Cotton effects in the visible region of the electronic circular dichroism (ECD) spectra. Density Functional Theory calculations suggested that the model oxindole adopts an () absolute stereochemical configuration, unveiling key interactions between the catalyst and substrates.
这项工作描述了1,3,5,7-四甲基-BODIPY与异吲哚酮衍生物之间首次对映选择性加成反应的开发。该反应利用双功能奎宁/方酰胺有机催化剂，在温和条件下得到九种新型手性BODIPY染料，对映选择性高达60%。合成的BODIPY-氧化吲哚表现出与母体BODIPY一致的高荧光发射，并呈现出可调颜色。一个代表性的例子表明，与荧光素相比，其量子产率高达0.78。值得注意的是，异吲哚酮骨架上新形成的碳立体中心在电子解耦的BODIPY发色团中诱导出可检测到的不对称性。这在电子圆二色性（ECD）光谱的可见光区域中存在的科顿效应得到了证实。密度泛函理论计算表明，模型氧化吲哚采用（）绝对立体化学构型，揭示了催化剂与底物之间的关键相互作用。
