diethylamino-sulfur trifluoride; ethanol in dichloromethane T=20°C; 2 h;

1.1: calcium chloride; sodium tetrahydroborate / dichloromethane / 12 h / 0 - 20 °C 1.2: 0 °C 2.1: Dess-Martin periodane / dichloromethane / 12 h / 0 - 20 °C 3.1: diethylamino-sulfur trifluoride / ethanol / dichloromethane / 2 h / 20 °C View Scheme

1: Dess-Martin periodane / dichloromethane / 12 h / 0 - 20 °C 2: diethylamino-sulfur trifluoride / ethanol / dichloromethane / 2 h / 20 °C View Scheme