water in methanol 50 h; Heating;

1.1: water / methanol / 2 h / Heating 2.1: diethyl ether / 0.25 h / -78 °C 2.2: 57 percent / 18 h / 20 °C 3.1: boron trifluoride diethyl etherate / CH2Cl2 / 2 h / -78 °C 3.2: 41 percent / 1 h / 0 °C View Scheme