1: 95 mg / 0.1 N HCl / tetrahydrofuran; diethyl ether / 1 h / Ambient temperature 2: H+ 3: 51 percent / CH2Cl2 / 2 h / Ambient temperature 4: 10 mg / AcOH, AcONa.3H2O, H2O, 7percent NaHCO3, HCl / dioxane / 3.5 h / 100 °C View Scheme

hydrogenchloride in tetrahydrofuran; diethyl ether 1 h; Ambient temperature;

sodium hydroxide in ethanol; water 2 h; Ambient temperature;