Using Common Alcohols to Transform N–H NHC-Palladium Complexes into Reactive Catalysts for the Suzuki–Miyaura Reaction with Aryl Chlorides

Abstract

We demonstrate that the generation of mixed NHC/phosphinite Pd catalysts from 2-phosphinoimidazole ligands using bulky alcohols provides highly active Pd catalysts for cross-coupling reactions. Mechanistic studies suggest that the rapid loss of bulkier phosphinites from the precatalyst leads to more rapid oxidative addition. These catalysts demonstrate a broad substrate scope in Suzuki–Miyaura reactions with aryl chlorides. Conversion of a methanol-derived catalyst into a tert-butanol-derived catalyst in situ also enables selective and sequential cross-coupling of bromochloroarenes.