1.1: hydrogenchloride / dichloromethane; diethyl ether / 0.25 h / 0 °C / |Inert atmosphere 2.1: lithium hydroxide hydrate / tetrahydrofuran; water / 5 h / 0 - 25 °C 2.2: pH 3 3.1: N-ethyl-N,N-diisopropylamine; 1-hydroxy-7-aza-benzotriazole; N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate / dichloromethane / 15 h / 0 - 25 °C / |Inert atmosphere 4.1: dichloromethane / 3 h / 0 - 25 °C / |Inert atmosphere 5.1: triethylamine / dichloromethane / 15 h / 0 - 25 °C / |Inert atmosphere 6.1: lithium hexamethyldisilazane; sulfur / tetrahydrofuran / 2.08 h / 25 °C / |Inert atmosphere View Scheme