1.1: sodium hydroxide / water; methanol / 0.5 h / |Sonication 1.2: pH 7 2.1: thionyl chloride / dichloromethane / 0 - 20 °C View Scheme

1: With sodium hydroxide in methanol; water 0.5 h; Sonication; 2: With hydrogenchloride in water pH=7;