Phosphine-Scavenging Cationic Gold(I) Complexes: Alternative Applications of Gold Cocatalysis in Fundamental Palladium-Catalyzed Cross-Couplings

We have demonstrated that air-stable cationic gold­(I) cocatalysts have the capacity to enhance the efficiency of palladium-catalyzed cross-couplings. Specifically, we determined that a 1:1 [Pd­{P­(t-Bu)₃}₂]/[Au­{P­(t-Bu)₃}­(NTf₂)] system provides superior reactivity relative to [Pd­{P­(t-Bu)₃}₂], across Suzuki–Miyaura, Stille, and Mizoroki–Heck reactions performed under mild conditions. Our results are consistent with cationic gold­(I) species serving primarily as phosphine scavengers in this chemistry, as recently predicted by density functional theory (DFT).