1.1: sulfuric acid / methanol / -10 - 0 °C 1.2: 2 h / -10 - 0 °C 1.3: pH 8 - 9 2.1: isopropyl alcohol / 3 h / 25 - 30 °C 3.1: sodium carbonate / water / pH 8 - 9 4.1: water; lithium hydroxide hydrate / tetrahydrofuran / 0 - 30 °C 5.1: water; tetrahydrofuran / 6 h / 25 - 30 °C 5.2: pH 2 View Scheme

1.1: sulfuric acid / methanol / -10 - 0 °C 1.2: 2 h / -10 - 0 °C 1.3: pH 8 - 9 2.1: isopropyl alcohol / 3 h / 25 - 30 °C 3.1: sodium carbonate / water / pH 8 - 9 4.1: water; lithium hydroxide hydrate / tetrahydrofuran / 0 - 30 °C 5.1: water; tetrahydrofuran / 6 h / 25 - 30 °C 5.2: pH 2 6.1: N-ethyl-N,N-diisopropylamine; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; benzotriazol-1-ol / N,N-dimethyl-formamide / 13 h / 0 - 30 °C 7.1: hydrogenchloride / methanol / 12 h / 25 - 45 °C View Scheme