反应详情

To a suspension of 2-bromo-1,3-thiazole-4-carboxylic acid (3.82 g, 18.4 mmol) and a catalytic amount of DMF in CH2Cl2 (100 mL) at 0° C. was slowly added thionyl chloride (14 mL of a 2M solution in CH2Cl2). The resulting mixture was stirred for 12 h at the room temperature and then heated to reflux for 1 h. The mixture was concentrated to dryness in vacuo. The white solid obtained was taken up in ethyl acetate, added to a pre-cooled (0° C.) 9-10% aqueous ammonium hydroxide solution (90 ml) and stirred for 1 h at 0° C. The organic layer was separated and the aqueous phase was extracted twice with ethyl acetate. The combined ethyl acetate solution was washed with brine, dried over magnesium sulfate and concentrated in vacuo, affording the title compound was obtained as an off-white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 7.60 (s, 1 H), 7.82 (s, 1 H), 8.22 (s, 1 H).

1. customat 0° C.
2. temperatureheated
3. temperatureto reflux for 1 h
4. concentrationThe mixture was concentrated to dryness in vacuo
5. customThe white solid obtained
6. additionadded to
7. stirringstirred for 1 h at 0° C
8. customThe organic layer was separated
9. extractionthe aqueous phase was extracted twice with ethyl acetate
10. washThe combined ethyl acetate solution was washed with brine
11. dry with materialdried over magnesium sulfate
12. concentrationconcentrated in vacuo