1: 30 percent / 2.)1M NaOH / 1.)THF, -10 degC, 15 min 2.)THF, water, -8 to 5 degC, 10 min then RT, 25 min. 2: NaBH4 / methanol / 2 h / Ambient temperature 3: 65 percent / silica gel, H2SO4 / dimethylsulfoxide; H2O / 24 h / Ambient temperature View Scheme

sodium in ethanol T=20 - 70°C; 18 h;