A photochemical synthesis of biologically relevant benzyl oxindoles is presented via electron-donor acceptor (EDA) complex strategy. This exogenous photocatalyst-free method describes the formation of a new electron donor-acceptor complex based on potassium carbonate and thianthrenium salts for C(sp2)–C(sp3) bond formation. This transition-metal free reaction allows a rapid increase in oxindoles molecular complexity chemical space, tolerating different functional groups as well as sophisticated biomolecules. The scalability and sustainability of this method is highlighted by an important waste recovery protocol. Mechanistic investigations support the formation of an EDA complex that induces a radical chain, and the applicability of this method is showcased by straightforward derivatization reactions.

中文翻译：

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使用铊盐和碳酸钾通过电子供体-受体复合物光活化获得苄基羟吲哚

通过电子供体受体（EDA）复合策略提出了生物相关的苄基羟吲哚的光化学合成。这种无外源光催化剂的方法描述了基于碳酸钾和铊盐的新电子供体-受体复合物的形成，用于形成 C(sp2)–C(sp3) 键。这种无过渡金属的反应可以快速增加羟吲哚分子化学空间的复杂性，耐受不同的官能团以及复杂的生物分子。重要的废物回收协议强调了该方法的可扩展性和可持续性。机理研究支持诱导自由基链的 EDA 复合物的形成，并且通过简单的衍生反应展示了该方法的适用性。