1: Et3N, 4-dimethylamino pyridine / -20 deg C, 1 h, 20 deg C, 16 h 2: 71 percent / NaHCO3 / CH2Cl2; H2O / 16 h / 20 °C 3: NaOH / methanol / 16 h / 80 °C View Scheme

1: Et3N, 4-dimethylamino pyridine / -20 deg C, 1 h, 20 deg C, 16 h 2: 71 percent / NaHCO3 / CH2Cl2; H2O / 16 h / 20 °C 3: NaOH / methanol / 16 h / 80 °C 4: diethyl ether / 0.08 h / 0 °C View Scheme