Thiadiazolidine 1-oxide systems for phosphine-free palladium-mediated catalysis

We herein report several highly active catalyst systems with thiadiazolidine 1-oxides as ligands for palladium in the Mizoroki–Heck reaction. Excellent yields of stilbenes derived from aryl iodides and bromides have been achieved using as little as 0.00002 mol % catalyst. The ligand/palladium system can be stored as a stock solution open to air at room temperature with no observable loss of activity for a period of several months.