Asymmetric Suzuki–Miyaura cross-coupling of aryl chlorides with enhancement of reaction time and catalyst turnover

A series of new chiral phosphonite ligands were evaluated for the palladium-catalyzed asymmetric Suzuki–Miyaura cross-coupling reactions of aryl chlorides. Ligand 4 gave 91% yield and 78% ee with 0.5 mol % catalyst loading for the coupling of aryl boronic acid and aryl chloride in 5 h. When the catalyst loading was lowered to 0.1 mol % the same reaction gave 75% yield and 76% ee.