potassium carbonate in acetonitrile T=20°C; 3 h; Reflux;

1: With sodium tetrahydroborate in methanol; water T=0 - 20°C; 2: With sodium hydroxide; water 2 h;

1: 100 percent / methanol; H2O / 0 °C 2: 100 percent / NaBH4 / methanol; H2O / 18.5 h / 0 - 23 °C View Scheme

1: 100 percent / methanol; H2O / 0 °C 2: 100 percent / NaBH4 / methanol; H2O / 18.5 h / 0 - 23 °C 3: (i-Pr)2NEt / tetrahydrofuran / 0.75 h / 23 °C View Scheme

1: 100 percent / methanol; H2O / 0 °C 2: 100 percent / NaBH4 / methanol; H2O / 18.5 h / 0 - 23 °C 3: (i-Pr)2NEt / tetrahydrofuran / 0.75 h / 23 °C 4: methanesulfonic acid / 18 h / 60 °C 5: NaCNBH3 / methanol / 0.08 h / 23 °C View Scheme

1: ethanol; water / 0.33 h / 0 °C 2: sodium tetrahydroborate / 3 h / 0 °C 3: N-ethyl-N,N-diisopropylamine / tetrahydrofuran / 1.33 h / 20 °C 4: sodium tetrahydroborate / water; methanol / 2 h / 0 - 20 °C 5: methanesulfonic acid / dichloromethane / 2 h / 20 °C / |Inert atmosphere; |Cooling with ice View Scheme