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.
Manna et al. (Wed,) studied this question.