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ChemicalBook CAS DataBase List 5-BROMO-2,3-DIFLUORO-BENZALDEHYDE
633327-22-7

5-BROMO-2,3-DIFLUORO-BENZALDEHYDE synthesis

2synthesis methods
-

Yield:633327-22-7 100%

Reaction Conditions:

with N-Bromosuccinimide;sulfuric acid at 60; for 12 h;

Steps:

1 Step 1

j0617j To a stirred solution of 2,3-difluorobenzaldehyde (XVIII) (75.0 g, 528 mmol, 1.0 eq) in H2S04 (565 mL) was added NBS (113 g, 633 mmol, 1.2 eq) in portions at 60 °C. The resulting mixture was stirred at 60 °C for 12 hr. LC/MS showed the reaction was completed. The reaction mixture was poured into ice water and petroleum ether (500 mL) and stirred for 10 mm, the organic layer was separated and concentrated under vacuum to give cmde product. The residue was purified column chromatography silica gel (100% petroleum ether) to give 5-bromo-2,3- difluorobenzaldehyde (XIX) (120 g, 543.0 mmol, quantitative yield). ESIMS found C7H3BrF2O mlz 221.1 (M+1).

References:

WO2017/24021,2017,A1 Location in patent:Paragraph 0616; 0617