Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea.
J Am Chem Soc. 2023 Jul 5;145(26):14510-14518. doi: 10.1021/jacs.3c04112. Epub 2023 Jun 20.
Exploiting β-scission in aminophosphoranyl radicals for radical-mediated transformations has been a longstanding challenge. In this study, we investigated the untapped potential of β-fragmentation in aminophosphoranyl radicals by leveraging the unique properties of the P-N bond and the substituents of P(III) reagents. Our approach carefully considers factors such as cone angle and electronic properties of phosphine and employs density functional theory (DFT) calculations to probe structural and molecular orbital influence. We successfully induced β-fragmentation through N-S bond cleavage of aminophosphoranyl radicals under visible light and mild conditions, generating a range of sulfonyl radicals derived from pyridinium salts via the photochemical activity of electron donor-acceptor (EDA) complexes. This innovative synthetic strategy exhibits broad applicability, including late-stage functionalization, and paves the way for valuable sulfonyl radical-mediated reactions, such as alkene hydrosulfonylation, difunctionalization, and pyridylic C-H sulfonylation.
利用β-断裂在氨基膦自由基中引发自由基介导的转化一直是一个长期存在的挑战。在这项研究中，我们通过利用 P-N 键的独特性质和 P(III)试剂的取代基，研究了氨基膦自由基中β-断裂未被开发的潜力。我们的方法仔细考虑了诸如膦的锥角和电子性质等因素，并采用密度泛函理论（DFT）计算来探测结构和分子轨道的影响。我们成功地通过可见光和温和条件下的 N-S 键断裂诱导了氨基膦自由基的β-断裂，通过电子给体-受体（EDA）配合物的光化学活性，生成了一系列源自吡啶翁盐的砜基自由基。这种创新的合成策略具有广泛的适用性，包括后期功能化，并为有价值的砜基自由基介导的反应铺平了道路，例如烯烃的氢亚磺酰化、双官能化和吡啶基 C-H 磺酰化。
