hydrogenchloride in 1,4-dioxane 6 h; Heating;

1: 8.0 g / methanol / 240 h / Ambient temperature 2: aq. LiOH / tetrahydrofuran; methanol / 3 h / Ambient temperature 3: Et3N, 1-hydroxybenzotriazole hydrate, 1,3-dicyclohexylcarbodiimide / dimethylformamide / 72 h / Ambient temperature 4: 0.13 g / 6N HCl / dioxane / 6 h / Heating View Scheme

1: 8.0 g / methanol / 240 h / Ambient temperature 2: aq. LiOH / tetrahydrofuran; methanol / 3 h / Ambient temperature 3: Et3N, 1-hydroxybenzotriazole hydrate, 1,3-dicyclohexylcarbodiimide / dimethylformamide / 72 h / Ambient temperature 4: 0.13 g / 6N HCl / dioxane / 6 h / Heating View Scheme

1.1: triethylamine / dichloromethane / 10 - 15 °C / Inert atmosphere 1.2: 16 h / 0 - 32 °C 2.1: triethylamine / 4-(N,N-dimethlyamino)pyridine / dichloromethane / 0 - 5 °C / Inert atmosphere 3.1: sodium hydrogencarbonate / ethylene glycol dimethyl ether / 25 - 85 °C / Reflux 4.1: sodium hydroxide; water / ethanol / 25 - 32 °C 4.2: 25 - 32 °C / pH 5.8 - 6.2 View Scheme

1.1: triethylamine / 4-(N,N-dimethlyamino)pyridine / dichloromethane / 0 - 5 °C / Inert atmosphere 2.1: sodium hydrogencarbonate / ethylene glycol dimethyl ether / 25 - 85 °C / Reflux 3.1: sodium hydroxide; water / ethanol / 25 - 32 °C 3.2: 25 - 32 °C / pH 5.8 - 6.2 View Scheme