1: 68 percent / aq. ethanol / 3 h / Heating 2: 90 percent / 15 percent NaOH / 8 h / Heating 3: 95 percent / 4-(Dimethylamino)pyridine, pyridine, SOCl2 / 12 h / 1.) -50 deg C to r. t.; 2.) 12 h, room temp. 4: 0.1 N NaOH / dioxane; H2O; methanol / 27 h 5: 80 percent / triethylamine, diphenyl-azidophosphate, molecular sieve / 2-methyl-propan-2-ol / 36 h / Heating View Scheme

sodium hydroxide

1: 68 percent / aq. ethanol / 3 h / Heating 2: 90 percent / 15 percent NaOH / 8 h / Heating 3: 95 percent / 4-(Dimethylamino)pyridine, pyridine, SOCl2 / 12 h / 1.) -50 deg C to r. t.; 2.) 12 h, room temp. View Scheme