反应详情

温度

200 °C

A 25 mL microwave reaction vial was charged with tert-butyl 2-(4-(chlorocarbonyl)phenoxy)acetate (0.815 g, 3.01 mmol) and pyridine (15 mL), (Z)-3-chloro-N′-hydroxy-4-isopropoxybenzimidamide (0.459 g, 2.007 mmol) was added. The vessel was capped and the reaction heated at 200° C. for 20 min under microwave irradiation (Biotage Optimizer, 300 W). The mixture was cooled, the reaction mixture was poured into stirring HCl (10%, 100 mL), the resulting suspension was filtered, the solid was washed by HCl (5%, 2×10 mL) and dried to afford grey solid, which was purified by RP-HPLC (A=50 mM ammonium acetate, B=acetonitrile; 30-95% B over 25.0 min (21.0 mL/min flow rate); 21.2×250 mm Thermo Hyperprep C18 column, 8 μm particles) to give 2-(4-(3-(3-chloro-4-isopropoxyphenyl)-1,2,4-oxadiazol-5-yl)phenoxy)acetic acid (0.246 g, 0.633 mmol, 31.5% yield) as white solid. LC/MS (Table 1, Method f) Rt=2.08 min.; MS m/z: 389.14 (M+H)+. 1H NMR (400 MHz, Solvent d-DMSO δ ppm 13.28-13.07 (m, 1H), 8.13 (d, J=9.03 Hz, 2H), 8.05 (d, J=2.13 Hz, 1H), 7.99 (dd, J=8.64, 2.15 Hz, 1H), 7.38 (d, J=9.04 Hz, 1H), 7.18 (d, J=9.06 Hz, 2H), 4.85 (s, 3H), 1.35 (d, J=6.03 Hz, 6H).

1. customA 25 mL microwave reaction
2. additionwas added
3. customThe vessel was capped
4. temperatureThe mixture was cooled
5. additionthe reaction mixture was poured
6. filtrationthe resulting suspension was filtered
7. washthe solid was washed by HCl (5%, 2×10 mL)
8. customdried
9. customto afford grey solid, which
10. customwas purified by RP-HPLC (A=50 mM ammonium acetate, B=acetonitrile