The Different Faces of [Ru(bpy)<sub>3</sub>Cl<sub>2</sub>] and <i>fac</i>[Ir(ppy)<sub>3</sub>] Photocatalysts: Redox Potential Controlled Synthesis of Sulfonylated Fluorenes and Pyrroloindoles from Unactivated Olefins and Sulfonyl Chlorides
作者:Santosh K. Pagire、Naoya Kumagai、Masakatsu Shibasaki
DOI:10.1021/acs.orglett.0c02760
日期:2020.10.16
A cascade alkene sulfonylation that simultaneously forges C–S and C–C bonds is a highly efficient and powerful approach for directly accessing structurally diverse sulfonylated compounds in a single operation. The reaction was enabled by visible-light-mediated regioselective radical addition of sulfonyl chlorides to 2-arylstyrenes using fac[Ir(ppy)3] as a photocatalyst, demonstrating its unique role
同时形成C–S和C–C键的级联烯烃磺酰化是一种高效且强大的方法,可通过一次操作直接访问结构多样的磺酰化化合物。使用fac [Ir(ppy)3 ]作为光催化剂,通过可见光介导的磺酰氯向2-芳基苯乙烯的区域选择性自由基加成反应,证明了其在光级联过程中执行原子转移自由基加成(ATRA)的独特作用然后进行光环化。通过这种光级联反应,以优异的产率制备了在光电子材料和药物化学领域中有用的新型的磺酰基取代的芴和吡咯并吲哚。相反,使用[Ru(bpy)3 Cl 2 ]催化剂具有较低的还原电位,仅导致在相同反应条件下形成C–S键并生成无环磺酰化2-芳基苯乙烯。室温稳定的磺酰氯和未活化的烯烃的广泛可用性提高了本室温光催化的合成效用,从而提供了一种经济高效的广谱方案。