1.1: sulfuric acid; water / ethyl acetate / 2 h / 0 - 5 °C 2.1: 3,5-dimethyl pyridine / dichloromethane / 1.08 h / 0 - 5 °C / |Inert atmosphere 2.2: 1 h / 0 - 5 °C / |Inert atmosphere View Scheme

1: With sulfuric acid; water in acetone T=0 - 5°C; 0.166667 h; 2: With sodium hydrogencarbonate; acetic acid in water; acetone T=0 - 15°C; 0.283333 - 0.416667 h; 3: With sodium acetate in water; acetone T=20°C; pH=5 - 5.5; 60.1667 h; Aqueous sodium acetate buffer;

1.1: sulfuric acid; water / ethyl acetate / 2 h / 0 - 5 °C 2.1: 3,5-dimethyl pyridine / dichloromethane / 1.08 h / 0 - 5 °C / |Inert atmosphere 2.2: 1 h / 0 - 5 °C / |Inert atmosphere View Scheme