Unlocking Catalyst Activation as a Critical Bottleneck in Cross-Coupling Reactions: Room-Temperature Couplings of Weak Nucleophiles Enabled by [Pd(1-MeNAP)TFA]2 Precatalysts.

The trifluoroacetate-bridged methylnaphthyl complex [Pd(1-MeNAP)TFA]2 is introduced as a bench-stable, highly soluble palladium source that consistently delivers exceptional catalytic activity. It reacts within minutes with even the most sterically demanding ligands to form monoligated Pd complexes and, upon exposure to nucleophiles, including weak, non-reducing N-nucleophiles, rapidly generates reactive Pd(0) species with the release of inert naphthalene derivatives. Across 15 representative transformations, catalysts generated in situ from [Pd(1-MeNAP)TFA]2 enable substantial reductions in reaction temperature, often by 80°C, while preserving established ligands and reaction conditions, thereby providing a drop-in solution to existing reactivity limitations. As a result, arylations of amides, carbamates, sulfonamides, amidines, ureas, cyclopropylamines, and trifluoroethylamines can be performed at room-temperature with markedly improved functional-group tolerance and compatibility with sensitive, coordinating heterocycles. Mechanistic studies reveal that catalyst activation, rather than catalytic turnover, has been the principal bottleneck in many cross-coupling reactions.