sodium hydride in N,N-dimethyl-formamide T=0°C;

1: sodium tetrahydroborate / methanol / 3 h / 20 °C 2: sodium hydride / N,N-dimethyl-formamide / 0 °C View Scheme

1: Dess-Martin periodane / dichloromethane / 5 h / 20 °C 2: sodium tetrahydroborate / methanol / 3 h / 20 °C 3: sodium hydride / N,N-dimethyl-formamide / 0 °C View Scheme

1: pyridine / 4 h / 20 °C 2: Dess-Martin periodane / dichloromethane / 5 h / 20 °C 3: sodium tetrahydroborate / methanol / 3 h / 20 °C 4: sodium hydride / N,N-dimethyl-formamide / 0 °C View Scheme

1: sodium carbonate; sulfuric acid / 3 h / 20 °C 2: pyridine / 4 h / 20 °C 3: Dess-Martin periodane / dichloromethane / 5 h / 20 °C 4: sodium tetrahydroborate / methanol / 3 h / 20 °C 5: sodium hydride / N,N-dimethyl-formamide / 0 °C View Scheme

sulfuric acid in acetic acid T=20°C; 24 h; Overall yield = 88 percent; Overall yield = 500 mg;