1.1: acetic acid / tetrahydrofuran; water / 20 °C 2.1: hydrogen; 5 palladium on charcoal / methanol / 28 h / 20 °C 3.1: potassium carbonate; tetrabutylammomium bromide / acetone / 30 °C 4.1: water; potassium hydroxide / methanol / 3 h / |Reflux 4.2: pH 2 View Scheme