in 1-methyl-pyrrolidin-2-one T=163°C; 2 h;

1: 86 percent / pyridine / ethyl acetate / 18 h / 20 °C 2: 48 percent / glacial AcOH; Br2 / 1.5 h / 15 °C 3: 94 percent / AcOH; conc. HCl / 24 h / 118 °C 4: 6.52 g / N-methylpyrrolidinone / 2 h / 163 °C View Scheme

1-methyl-pyrrolidin-2-one T=163°C; 2 h;

1: 48 percent / glacial AcOH; Br2 / 1.5 h / 15 °C 2: 94 percent / AcOH; conc. HCl / 24 h / 118 °C 3: 6.52 g / N-methylpyrrolidinone / 2 h / 163 °C View Scheme

1: 94 percent / AcOH; conc. HCl / 24 h / 118 °C 2: 6.52 g / N-methylpyrrolidinone / 2 h / 163 °C View Scheme

1: 93 percent / aq. KOH; H2O2 / 2 h / 130 °C 2: 97 percent / tetrahydrofuran / 6 h / 20 °C 3: 90 percent / DMAP / 3 h / 80 °C 4: 90 percent / pyridine / dimethylformamide / 2 h / 20 °C 5: 0.230 g / methanol; tetrahydrofuran / 26 h / 20 °C 6: 76 percent / 48percent aq. HBr / 7 h / 120 °C 7: 98 percent / DMAP; Et3N / CH2Cl2 / 0.5 h / 20 °C 8: 51 percent / NBS; dibenzoyl peroxide / CCl4 / 3.83 h / 85 °C / Irradiation 9: 73 percent / 2,6-lutidine / dimethylformamide / 5.5 h / 120 °C 10: 80 percent / aq. NaOH / tetrahydrofuran / 1 h / 20 °C 11: 94 percent / Et3N / CH2Cl2 / 0.92 h 12: 77 percent / CH2Cl2 / 2.5 h / 20 °C 13: 0.142 g / TFA / CH2Cl2 / 0.92 h / 20 °C 14: PyBOP; diisopropylethylamine / dimethylformamide / 3 h View Scheme

1: 93 percent / aq. KOH; H2O2 / 2 h / 130 °C 2: 97 percent / tetrahydrofuran / 6 h / 20 °C 3: 90 percent / DMAP / 3 h / 80 °C 4: 90 percent / pyridine / dimethylformamide / 2 h / 20 °C 5: 0.230 g / methanol; tetrahydrofuran / 26 h / 20 °C 6: 76 percent / 48percent aq. HBr / 7 h / 120 °C 7: 98 percent / DMAP; Et3N / CH2Cl2 / 0.5 h / 20 °C 8: 51 percent / NBS; dibenzoyl peroxide / CCl4 / 3.83 h / 85 °C / Irradiation 9: 73 percent / 2,6-lutidine / dimethylformamide / 5.5 h / 120 °C View Scheme

1: 93 percent / aq. KOH; H2O2 / 2 h / 130 °C 2: 97 percent / tetrahydrofuran / 6 h / 20 °C 3: 90 percent / DMAP / 3 h / 80 °C 4: 90 percent / pyridine / dimethylformamide / 2 h / 20 °C 5: 0.230 g / methanol; tetrahydrofuran / 26 h / 20 °C 6: 76 percent / 48percent aq. HBr / 7 h / 120 °C 7: 98 percent / DMAP; Et3N / CH2Cl2 / 0.5 h / 20 °C View Scheme

potassium hydroxide; dihydrogen peroxide T=130°C; 2 h;

1: 93 percent / aq. KOH; H2O2 / 2 h / 130 °C 2: 97 percent / tetrahydrofuran / 6 h / 20 °C 3: 90 percent / DMAP / 3 h / 80 °C 4: 90 percent / pyridine / dimethylformamide / 2 h / 20 °C 5: 0.230 g / methanol; tetrahydrofuran / 26 h / 20 °C 6: 76 percent / 48percent aq. HBr / 7 h / 120 °C 7: 98 percent / DMAP; Et3N / CH2Cl2 / 0.5 h / 20 °C 8: 51 percent / NBS; dibenzoyl peroxide / CCl4 / 3.83 h / 85 °C / Irradiation View Scheme