Crude product was triturated with cold petroleum ether; solid obtained was filtered and dried. Yield of the product was 20.0 g (80.6%) as white solid. M. pt: 103.4–104.8 °C. Mol. Wt: 257.23, LCMS: 258.1(M+1). 1H NMR (CDCl3, 400 MHz); δ 8.12(m, 1H), 7.86(m, 2H), 7.47(m, 3H), 6.97(m, 3H). 13C NMR (CDCl3, 300 MHz): 170.42, 165.6, 162.77, 15752, 130.26, 128.11, 127.22, 125.78, 112.3, 104.9, 99.61. To the solution of 3-(2,4-difluorophenyl)-5-phenylisoxazole (20.0 g, 77.82 mmol) in glacial acetic
selleck chemicals acid (200 mL) was added N-bromosuccinimide10 (16.6 g, 93.25 mmol), in one lot at RT and then reaction mass was heated to 100 °C for 16 h. RM was cooled to RT and acetic acid was removed under reduced pressure. The residue obtained was
diluted with ethyl acetate (500 mL), washed with water, saturated brine solution, dried over Na2SO4, and evaporated under reduced pressure. Crude product was triturated with cold petroleum ether; solid obtained was filtered and dried. Yield of the product was 20.0 g (77%) as white solid. M. pt: 103.4–104.8 °C. Mol. Wt: 336.13, LCMS: 337.9(M+1). 1H NMR (CDCl3, 400 MHz): δ 8.11(m, 2H), 7.56(m, 4H), 7.04(m, 2H). 13C NMR (CDCl3, 400 MHz): 165.6, 163.2, 161.82, 159.17, 132.53, 132.24, 130.85, 128.9, 126.9, 126.96, 126.47, 112.01, 104.88, 91.03. To a solution of 4-bromo-3-(2,4-difluorophenyl)-5-phenylisoxazole (0.5 g, 1.488 mmol) in 10 mL of dioxane was added corresponding arylboronicacid11 (2.232 mmol), selleck inhibitor Pd (PPh3)4 (0.0744 mmol), potassium carbonate (2.232 mmol), and water (1 mL). The RM was then heated to 100 °C under microwave irradiation for a period of 30 min. After completion of reaction (monitored by TLC) RM was concentrated to dryness under reduced pressure and re-dissolved in Ethyl Acetate, then organic layer washed with brine solution, dried over sodium sulphate and evaporated under reduced pressure. Crude product was purified by Column chromatography using Pet ether:
Ethyl Acetate. Yield: 85% as white powder. M. pt:149.4–150.4 °C. Mol. Wt.: 351.32 for C21H12F3NO, LCMS: 351.9(M+1); 1H NMR (CDCl3, 400 MHz): δ 7.58(d, J = 8.2 Hz, 2H), 7.39(m, 4H), 7.17(m, 2H), 7.03(t, J = 8.8 Hz, Calpain 2H), 6.93(t, J = 7.3 Hz, 1H), 6.83(t, J = 7.5 Hz, 1H). 13C NMR (CDCl3, 400 MHz): 167.8, 165.9, 164.7, 160.8, 159.7, 158.7, 156.8, 132.9, 132.5, 129.65, 129.05, 129.26, 127.31, 127.24, 124.7, 116.8, 116.9, 113.6, 112.9, 104.8, 101.2. Yield: 82% as white powder. M. pt: 146.2–147.3 °C. Mol. Wt.: 351.32 for C21H12F3NO, LCMS: 352(M+1); 1H NMR (CDCl3, 400 MHz): δ 7.58(d, J = 7.5 Hz, 2H), 7.41(m, 4H), 7.27(m, 1H), 7.06(t, J = 8.2 Hz, 1H), 6.95(m, 3H), 6.82(t, J = 7.8 Hz, 1H). 13C NMR (CDCl3, 400 MHz): 166.22, 164.7, 159.7, 158.2, 156.7, 133.4, 132.5, 129.48, 129.5, 127.26, 124.7, 122.7, 116.37, 115.6, 114.7, 114.8, 113.6, 112.8, 105.5, 104.8, 104.1, 95.4. Yield: 78% as white powder. M. pt: 156.7–157.3 °C. Mol. Wt.: 401.