Pd1Aul/Graphene: Highly Efficient Bimetallic Single-Atom Catalysts for C–C Coupling from C–B Bond Activation

Bimetallic single-atom catalysts (SACs) represent an emerging paradigm beyond single-atom catalysts for enabling synergistic catalysis. The homocoupling of arylboronic acids via C–B bond activation to form C–C bonds has been demonstrated to be entirely inert with Pd or Au SACs. This study achieves a breakthrough by developing a bimetallic single-atom catalyst (Pd1Au1/graphene), which delivers outstanding performance with a TON up to 19,192 and cycling stability (>90% yield after seven cycles). Through comprehensive experiments and theoretical calculations, we have identified a structure of PdN4-AuN4/graphene, where adjacent Pd and Au atoms form a synergistic active center. This promotes simultaneous aromatic boronic acid substrate activation and significantly reduces the reaction energy barrier of the oxidative addition step, thereby enabling a pathway inaccessible to isolated single atoms. This work not only provides an efficient catalyst for organic synthesis but also validates the fundamental principle of synergistic catalysis in bimetallic single-atom catalysts, offering a universal design strategy for addressing challenging transformations.