N-benzyl-N,N,N-triethylammonium chloride; sodium hydroxide in dichloromethane T=0 - 20°C; 1.33333 h;

1: 1-benzenesulfonyl-5-bromo-1H-pyrrolo[2,3-b]pyridine-3-carboxylic acid methyl ester With lithium diisopropyl amide in tetrahydrofuran T=-78°C; 0.75 h; 2: methyl iodide in tetrahydrofuran T=-78 - 10°C; 3.5 h; 3: With sodium dihydrogenphosphate in tetrahydrofuran T=10 - 20°C;

1.1: triethylamine / copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride / tetrahydrofuran / 1 h / 0 - 20 °C 2.1: potassium tert-butylate / tert-butyl alcohol / 1 h / 85 °C 3.1: AlCl3, aluminium chloride / dichloromethane / 0.83 h 3.2: 18 h 4.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane / 1.33 h / 0 - 20 °C View Scheme

1.1: sulfuric acid; KIO3 / 100 °C 1.2: 1.5 h 2.1: triethylamine / copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride / tetrahydrofuran / 1 h / 0 - 20 °C 3.1: potassium tert-butylate / tert-butyl alcohol / 1 h / 85 °C 4.1: AlCl3, aluminium chloride / dichloromethane / 0.83 h 4.2: 18 h 5.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane / 1.33 h / 0 - 20 °C View Scheme

1.1: AlCl3, aluminium chloride / dichloromethane / 0.83 h 1.2: 18 h 2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane / 1.33 h / 0 - 20 °C View Scheme

1.1: potassium tert-butylate / tert-butyl alcohol / 1 h / 85 °C 2.1: AlCl3, aluminium chloride / dichloromethane / 0.83 h 2.2: 18 h 3.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane / 1.33 h / 0 - 20 °C View Scheme