sodium tetrahydroborate; boron trifluoride diethyl etherate in diethyl ether; diethylene glycol dimethyl ether 1.) 0 deg C, 30 min, 2.) room temperature, 1 h;

1: 1.) POCl3, 2.) Na2CO3 / 1.) 100 deg C, 2 h, 2.) H2O, 100 deg C, 10 min 2: 67 percent / boron trifluoride-diethyl ether complex, NaBH4 / bis-(2-methoxy-ethyl) ether; diethyl ether / 1.) 0 deg C, 30 min, 2.) room temperature, 1 h View Scheme

1: 19 percent / NaH / dimethylformamide / 1.) room temperature, 15 min, 2.) 70 deg C, 30 min, 3.) reflux, 15 h 2: 1.) POCl3, 2.) Na2CO3 / 1.) 100 deg C, 2 h, 2.) H2O, 100 deg C, 10 min 3: 67 percent / boron trifluoride-diethyl ether complex, NaBH4 / bis-(2-methoxy-ethyl) ether; diethyl ether / 1.) 0 deg C, 30 min, 2.) room temperature, 1 h View Scheme

1: 45 percent / NaH / dimethylformamide / 20 h 2: 1.) POCl3, 2.) Na2CO3 / 1.) 100 deg C, 2 h, 2.) H2O, 100 deg C, 10 min 3: 67 percent / boron trifluoride-diethyl ether complex, NaBH4 / bis-(2-methoxy-ethyl) ether; diethyl ether / 1.) 0 deg C, 30 min, 2.) room temperature, 1 h View Scheme