Sterically demanding, water-soluble alkylphosphines as ligands for high activity Suzuki coupling of aryl bromides in aqueous solvents.

[reaction: see text]. Sterically demanding, water-soluble alkylphosphines have been found to give highly active catalysts for Suzuki coupling of aryl bromides in aqueous solvents. A variety of aryl bromides and boronic acids were coupled in excellent yield. Turnover numbers up to 734 000 mmol/mmol Pd have been achieved under mild conditions.