Herein we report a novel visible-light-mediated external reductant-free reductive cross coupling for the construction of C sp²–C sp³ bonds. A variety of benzylammonium salts underwent selective coupling with (hetero)aryl nitriles to deliver important diarylmethanes under mild reaction conditions. Importantly, photocatalysts can be omitted for many cases, which might involve the electron donor acceptor (EDA) complex. Mechanistic studies indicated benzylic radicals might be involved as the key intermediates. Moreover, the in situ generated NMe₃ via cleavage of C–N bond in ammonium salts acts as the electron donor, thus avoiding the use of external-reductant.

在这里，我们报告了一种新型的可见光介导的无外部还原剂的还原性交叉偶联，用于构建C sp ² –C sp ³键。各种苄基铵盐与（杂）芳基腈进行选择性偶联，以在温和的反应条件下提供重要的二芳基甲烷。重要的是，在许多情况下可以省略光催化剂，这可能涉及电子给体受体（EDA）配合物。机理研究表明，苄基可能是关键的中间体。此外，通过裂解铵盐中的C–N键原位生成的NMe ₃充当电子给体，因此避免了使用外部还原剂。