Hydrogen Bromide → 2-Bromo-4-(trifluoromethyl)-1,3-thiazole

Temperature

0 °C

2-Amino-4-(trifluoromethyl)thiazole (Wako Pure Chemical Industries, Ltd., 500 mg) was added to 48% aqueous hydrogen bromide (6 ml) and, under ice-cooling, sodium nitrite (266 mg) dissolved in water (1 ml) was added dropwise thereto. The mixture was stirred at 0° C. for 1 hr. A sodium hydrogen sulfite aqueous solution, and then an aqueous sodium hydroxide solution were added, and the mixture was extracted with diethyl ether. The organic layer was dried and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (elution solvent: ethyl acetate-hexane (1:9)) to give 2-bromo-4-(trifluoromethyl)thiazole (167 mg, yield 24%).

1. temperaturecooling
2. additionwas added dropwise
3. extractionthe mixture was extracted with diethyl ether
4. customThe organic layer was dried
5. customthe solvent was evaporated under reduced pressure
6. customThe obtained residue was purified by silica gel column chromatography (elution solvent: ethyl acetate-hexane (1:9))

ORD record

ord-a61a544eec764607878ecb9d6acd7b3d

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07994196B2