Scheme 4. Scope of Ir-catalyzed asymmetric hydrogenation of 1,4-benzodioxinesa. a Reaction conditions: 5 (0.2 moll), [Ir(cod)Cl]2 (0.002 mmol), (R,R,R,R)-BIDIME-dimer L5 (0.006 mmol), THF (0.3 mL), MeOH (0.3 mL), AcOH (8 mmol), H2 (600 psi), 50 °C for 24 h. Isolated yield. Enantiomeric ratio was determined by chiral SFC or HPLC.
