反应详情

Using the (R,R)-(salen)Co(II) precatalyst of 1 (91 mg, 0.15 mmol, 0.005 equiv), (+/−)-glycidyl butyrate (4.32 g, 30.0 mmol), AcOH (32 mL, 0.6 mmol, 0.02 equiv), 0.3 mL THF, and H2O (297 mL, 16.5 mmol, 0.55 equiv) and a procedure analogous to the one outlined for 5b, (S)-glycidyl butyrate 5d (1.90 g, 13.2 mmol, 44%) was obtained as a clear oil by vacuum distillation of the reaction mixture (30° C., 0.5 torr). The product was determined to be >99% ee by conversion to and analysis of the 2-napthylsulfide (obtained by ring opening with 2-napthalenethiol in methanol using 1 equiv TEA at 0° C.; Chiralcel OD, 97:3 hexanes:EtOH, 1 mL/min, 260 nm).