28314-81-0

28314-81-0 - Names and Identifiers

Name	3-bromo-2,6-difluorobenzoic acid
Synonyms	3-bromo-2,6-difluorobenzoic acid Benzoic acid, 3-broMo-2,6-difluoro-
CAS	28314-81-0
InChI	InChI=1/C7H3BrF2O2/c8-3-1-2-4(9)5(6(3)10)7(11)12/h1-2H,(H,11,12)

28314-81-0 - Physico-chemical Properties

Molecular Formula	C7H3BrF2O2
Molar Mass	237.00
Density	1.872g/cm³
Melting Point	137-139℃
Boling Point	279.2°C at 760 mmHg
Flash Point	122.7°C
Vapor Presure	0.00194mmHg at 25°C
Storage Condition	Room Temprature
Refractive Index	1.558
Use	Use 3-bromo-2, 6-difluorobenzoic acid can be used as an intermediate in the synthesis of medicine.

28314-81-0 - Upstream Downstream Industry

Raw Materials

2,4-Difluorobenzoic acid
1-Bromo-2,4-difluorobenzene
1-Bromo-2,6-difluorobenzene
2,6-Difluorobenzoic acid
CARBON DIOXIDE
1,3-Difluorobenzene

28314-81-0 - Preparation

3-bromo-2, 6-difluorobenzoic acid can be prepared from 1-bromo-2, 4-difluorobenzene as the reaction raw material and reacted with carbon dioxide to prepare another intermediate 3-bromo-2, 6-difluorophenylcarbamate tert-butyl ester.
Preparation of 3-bromo-2, 6-difluorobenzoic acid: Diisopropylamine (8.1mL,57.0mmol) and THF(260mL) were added to the dried 2-neck round bottom flask under argon at room temperature. The solution was cooled to -70°C in a dry ice-acetone bath. Drop addition of n-butyllithium (2.0M in cyclohexane, 25.9mL,51.8mmol) through a syringe, the resulting reaction was briefly warmed to 0°C, and then cooled back to -70°C. Drop 1-bromo -2, 4-difluorobenzene (5.9mL,52.0mmol) to the cold solution through a syringe. After adding, the reaction was kept at -70°C for 1 hour. Add carbon dioxide (5-9g tablets, rinse with dry THF in advance) to the solution. Remove the Ar bladders and replace them with bubblers to allow venting. The resulting reaction was then warmed to room temperature and quenched to pH-7-8 with a saturated NH4Cl aqueous solution. The aqueous mixture was washed with EtOAc, acidified to pH-2-3 with 6NHCl aqueous solution, and extracted with EtOAc. The organic extract was washed with brine, dried (Na2SO4), filtered, and concentrated under vacuum to obtain 10.9g(89%) 3-bromo-2, 6-difluorobenzoic acid: 1HNMR(400MHz,DMSO-d6)& delta;7.25(m,1H)7.92(m,1H).

Last Update：2024-04-10 22:29:15