Potassium Carbonate → 2-(1-(5-Bromo-2-nitrophenyl)-4-(tert-butoxycarbonyl)piperazin-2-yl)acetic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

4-Bromo-2-fluoro-1-nitrobenzene (5.3 g, 24.1 mmol) was dissolved in acetonitrile (70 mL) and water (10 mL). To this mixture, potassium carbonate (10 g, 72.3 mmol) and 2-(4-(tert-butoxycarbonyl)piperazin-2-yl)acetic acid (7.1 g, 28.9 mmol) were added. The resulting mixture was heated at 70° C. for 2 days. The mixture thus obtained was concentrated and ethyl acetate was added. 1 N HCl was then added slowly to the reaction solution until pH=6. The water layer was separated and washed multiple times with ethyl acetate. The organic layers thus obtained were combined and concentrated. The crude material thus obtained was purified by silica gel chromatography eluting with a gradient of 0% to 10% of methanol in dichloromethane to afford the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 12.28 (br s), 7.71-7.83 (m, 1 H), 7.56-7.66 (m, 1 H), 7.30-7.40 (m, 1 H), 3.56-3.82 (m, 3 H), 3.33-3.44 (m, 1 H), 2.99-3.24 (m, 2 H), 2.87 (m, 1 H), 2.32-2.47 (m, 1 H), 2.17-2.29 (m, 1 H), 1.32-1.51 (s, 9 H); MS (DCI+) m/z 444.1 (M+H)+.

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