Bis(NHC)-Pd-catalyzed one-pot competitive C-C*C-C, C-C*C-O, C-C*C-N, and C-O*C-N cross-coupling reactions on an aryl di-halide catalyzed by a homogenous basic ionic liquid (TAIm[OH]) under base-free, ligand-free, and solvent-free conditions

Bis(NHC)-Pd-catalyzed competitive asymmetrical C-C*C-C, C-C*C-O, C-C*C-N, and O-C*C-N cross-coupling reactions were performed via the one-pot strategy in the presence of a new ionic liquid, which played the roles of solvent, base, and ligand simultaneously. The ionic liquid was prepared based on a methyl imidazolium moiety with hydroxyl counter anions via a Hofmann elimination on a 1,3,5-triazine framework (TAIm[OH]). Pd ions could be efficiently coordinated through the bis(NHC)-ligand moiety in the ionic liquid. Based on differences in the competitive kinetics of C-C cross-coupling reactions (Heck, Suzuki, and Sonogashira) with C-N and C-O cross-coupling reactions, and also differences in the kinetics of aryl halides, the coupling reactions could be selectively performed with a low amount of by-products. The competitive cross-coupling reactions were thus performed with high selectivity under mild reaction conditions.