Oligoether substituted bis-NHC palladium and platinum complexes for aqueous Suzuki–Miyaura coupling and hydrosilylation

•Synthesis and characterization of new palladium and platinum complexes.•Chelating N-heterocyclic carbene ligands with PEG groups.•Excellent solubility in a variety of organic solvents as well as water.•High activity for C–C coupling reactions in an aqueous reaction medium.

The synthesis of four oligo ethylene glycol substituted, bis-NHC palladium(II) and platinum(II) complexes is reported. Two of them were characterized by solid state structures. All complexes show excellent solubility in a variety of organic solvents and water. The palladium complexes were tested in the Suzuki–Miyaura coupling reaction and the platinum complexes in the hydrosilylation reaction of alkynes in aqueous solvent mixtures. All show a high catalytic activity at ppm level catalyst-loading under very mild reaction conditions.

Graphical abstractFour oligoether substituted bis-NHC complexes (palladium, platinum) were synthesized. They show excellent solubility in a variety of solvents, and were tested as catalysts in the Suzuki–Miyaura coupling (Pd) and catalytic hydrosilylation reaction (Pt) in aqueous solvent mixtures.Figure optionsDownload full-size imageDownload as PowerPoint slide