1: 98.2 percent / Et3N / diethyl ether / 0.5 h / Ambient temperature 2: 87.6 percent / NaBH4, NaH, 2-propanol / dioxane / 1.) 70 deg C, 2.) reflux, 1 h 3: 91.6 percent / m-chloroperbenzoic acid / CH2Cl2 / Ambient temperature 4: tert-BuOK / dimethylsulfoxide; tetrahydrofuran / 0.17 h / Ambient temperature 5: Al-Hg / tetrahydrofuran; H2O / 0.67 h / Heating View Scheme

thionyl chloride 3 h; Heating;

1: aq. HNO3 2: SOCl2 View Scheme