1: 79 percent / aq. NaOH / methanol / 2 h / Heating 2: 85 percent / pyridine / 20 h / 20 °C 3: 1.) 1,1'-carbonyldiimidazole / 1.) DMF, 40 deg C, 30 min, 2.) 20 deg C, 11 h 4: methanolic NaOH 5: Et3N / tetrahydrofuran; CH2Cl2 / 0.17 h / 0 °C 6: LiCl / dimethylformamide / 0.08 h / 110 °C 7: HBr/AcOH / 4 h / 20 °C 8: methanol / 24 h / 20 °C View Scheme

1: 85 percent / pyridine / 20 h / 20 °C 2: 1.) 1,1'-carbonyldiimidazole / 1.) DMF, 40 deg C, 30 min, 2.) 20 deg C, 11 h 3: methanolic NaOH 4: Et3N / tetrahydrofuran; CH2Cl2 / 0.17 h / 0 °C 5: LiCl / dimethylformamide / 0.08 h / 110 °C 6: HBr/AcOH / 4 h / 20 °C 7: methanol / 24 h / 20 °C View Scheme

1: 1.) 1,1'-carbonyldiimidazole / 1.) DMF, 40 deg C, 30 min, 2.) 20 deg C, 11 h 2: methanolic NaOH 3: Et3N / tetrahydrofuran; CH2Cl2 / 0.17 h / 0 °C 4: LiCl / dimethylformamide / 0.08 h / 110 °C 5: HBr/AcOH / 4 h / 20 °C 6: methanol / 24 h / 20 °C View Scheme

1: HBr/AcOH / 4 h / 20 °C 2: methanol / 24 h / 20 °C View Scheme

1: Et3N / tetrahydrofuran; CH2Cl2 / 0.17 h / 0 °C 2: LiCl / dimethylformamide / 0.08 h / 110 °C 3: HBr/AcOH / 4 h / 20 °C 4: methanol / 24 h / 20 °C View Scheme

in methanol T=20°C; 24 h; Yield given;