1: With sodium hydroxide; bromine in water T=0°C; 0.0833333 h; 2: 2-oxy-pyridine-3-carboxylic acid With sodium hydroxide in water T=50°C; 44 h; 3: With hydrogenchloride in water T=0°C; pH=2;

sodium hydroxide; bromine

1: 5-Bromo-2-hydroxy-3-pyridinecarboxylic acid With thionyl chloride in DMF (N,N-dimethyl-formamide) T=0°C; 2 h; Heating / reflux; 2: methanol in DMF (N,N-dimethyl-formamide) T=0°C; Heating / reflux; 3: With sodium hydrogencarbonate in water T=0°C;

1.1: 99 percent / thionyl chloride / dimethylformamide / 4 h / 70 °C 2.1: isobutyl chloroformate; Et3N / tetrahydrofuran / 0 °C 2.2: 70 percent / NaBH4 / tetrahydrofuran / 18 h / 0 - 23 °C View Scheme

1.1: thionyl chloride; N,N-dimethyl-formamide / toluene / 7 h / 70 - 105 °C / |Large scale 2.1: sodium hydrogencarbonate / acetonitrile / 0.5 h / 25 °C / |Large scale 2.2: 22 h / 20 - 34 °C / |Large scale 3.1: tetrahydrofuran / 14.25 h / 5 - 90 °C / |Inert atmosphere; |Large scale 4.1: sodium hexamethyldisilazane / tetrahydrofuran / 4 h / 50 - 55 °C / |Inert atmosphere; |Large scale 5.1: tetrahydrofuran / 12 h / 25 - 30 °C / |Inert atmosphere; |Large scale View Scheme

1.1: thionyl chloride; N,N-dimethyl-formamide / toluene / 7 h / 70 - 105 °C / |Large scale 2.1: sodium hydrogencarbonate / acetonitrile / 0.5 h / 25 °C / |Large scale 2.2: 22 h / 20 - 34 °C / |Large scale 3.1: tetrahydrofuran / 14.25 h / 5 - 90 °C / |Inert atmosphere; |Large scale 4.1: sodium hexamethyldisilazane / tetrahydrofuran / 4 h / 50 - 55 °C / |Inert atmosphere; |Large scale 5.1: tetrahydrofuran / 12 h / 25 - 30 °C / |Inert atmosphere; |Large scale 6.1: palladium diacetate; biphenyl-2-yl-di-tert-butyl-phosphane; potassium phosphate / toluene / 24 h / |Inert atmosphere; |Reflux View Scheme

1.1: thionyl chloride; N,N-dimethyl-formamide / toluene / 7 h / 70 - 105 °C / |Large scale 2.1: sodium hydrogencarbonate / acetonitrile / 0.5 h / 25 °C / |Large scale 2.2: 22 h / 20 - 34 °C / |Large scale 3.1: tetrahydrofuran / 14.25 h / 5 - 90 °C / |Inert atmosphere; |Large scale 4.1: sodium hexamethyldisilazane / tetrahydrofuran / 4 h / 50 - 55 °C / |Inert atmosphere; |Large scale View Scheme

thionyl chloride in N,N-dimethyl-formamide T=70°C; 4 h;

thionyl chloride; N,N-dimethyl-formamide in toluene T=70 - 105°C; 7 h; Large scale;

1.1: thionyl chloride; N,N-dimethyl-formamide / toluene / 7 h / 70 - 105 °C / |Large scale 2.1: sodium hydrogencarbonate / acetonitrile / 0.5 h / 25 °C / |Large scale 2.2: 22 h / 20 - 34 °C / |Large scale 3.1: tetrahydrofuran / 14.25 h / 5 - 90 °C / |Inert atmosphere; |Large scale 4.1: sodium hexamethyldisilazane / tetrahydrofuran / 4 h / 50 - 55 °C / |Inert atmosphere; |Large scale 5.1: tetrahydrofuran / 12 h / 25 - 30 °C / |Inert atmosphere; |Large scale 6.1: palladium diacetate; triphenylphosphine; sodium hydride / toluene; mineral oil / 3.5 h / 60 - 100 °C / |Inert atmosphere; |Large scale 7.1: sodium hydroxide / water / 8 h / 80 °C / |Inert atmosphere; |Large scale 8.1: sodium tetrahydroborate; hydrogenchloride / tetrahydrofuran; diethylene glycol dimethyl ether / 6.5 h / 0 - 25 °C / |Inert atmosphere; |Large scale 9.1: triphenylphosphine; di-isopropyl azodicarboxylate / ethylene glycol dimethyl ether / 2.17 h / 25 - 30 °C / |Inert atmosphere; |Large scale 9.2: 10 h / -15 - 22 °C / |Inert atmosphere; |Large scale 10.1: sodium carbonate / methanol; dichloromethane / 0.75 h / 25 °C / pH 10 / |Darkness; |Inert atmosphere; |Large scale 10.2: 2.25 h / 30 °C / |Darkness; |Inert atmosphere; |Large scale View Scheme