1.1: 1,1'-carbonyldiimidazole / 1 h / 20 - 25 °C 1.2: 2.5 h / 95 °C 2.1: 0.75 h / 0.28 - 32 °C / |Inert atmosphere 2.2: 3.33 h / 20 - 85 °C / |Inert atmosphere 2.3: 0.5 h / pH Ca.1 / |Inert atmosphere 3.1: hydrogen; 5 palladium on charcoal / isopropanol acetate; methanol / 2 h / 0 °C / 775.74 Torr 4.1: N-ethyl-N,N-diisopropylamine; benzenesulfonic Acid / acetonitrile / 20 - 50 °C / pH 8 - 9 4.2: 8 h / 20 °C 5.1: lithium hydroxide hydrate / tetrahydrofuran / 1 h / 0.14 - 40 °C 5.2: 20 °C / pH 1.9 View Scheme