Hydrochloric Acid → 3-Bromo-5-trifluoromethylbenzenesulfonamide

Temperatur

-5 °C

3-Amino-5-bromobenzotrifluoride was added to concentrated hydrochloric acid (20 ml) and cooled to −5° C. A saturated solution of sodium nitrite (3.88 g) in water (4 ml) was dropwise added at such a rate to maintain the temperature below 0° C. Magnesium chloride (8 g) was added (CARE: exotherm) and the resulting mixture added with stirring to a saturated solution of sulfur dioxide in acetic acid (37.5 ml) and toluene (20 ml), containing cupric chloride (2.75 g) at room temperature. The mixture was stirred for 16 hours, poured into water and extracted into toluene. The combined toluene extracts were washed with water, dilute sodium hydrogen carbonate, dried over anhydrous magnesium sulfate and concentrated. The residue was dissolved in tetrahydrofuran (200 ml) and 880 ammonia (50 ml) was added to the solution. The mixture was stirred at room temperature for 4 hours and then concentrated under reduced pressure. The residue was partitioned between water and ethyl acetate. The combined ethyl acetate extracts were dried over anhydrous magnesium sulfate and concentrated to afford the sub-title compound as a solid (4.2 g).

1. temperatureto maintain the temperature below 0° C
2. additionthe resulting mixture added
3. extractionextracted into toluene
4. washThe combined toluene extracts were washed with water, dilute sodium hydrogen carbonate
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated
7. dissolutionThe residue was dissolved in tetrahydrofuran (200 ml)
8. addition880 ammonia (50 ml) was added to the solution
9. stirringThe mixture was stirred at room temperature for 4 hours
10. concentrationconcentrated under reduced pressure
11. customThe residue was partitioned between water and ethyl acetate
12. dry with materialThe combined ethyl acetate extracts were dried over anhydrous magnesium sulfate
13. concentrationconcentrated

ORD-Eintrag

ord-83fc3015a7f246068e62c58b29320cda

Quelldatensatz

uspto-grants-2001_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06300352B1