Dichloromethane → 4-Bromo-2-chloro-5-fluorophenol

Temperatur

75 °C

2-Chloro-5-fluorophenol (24.1 g, 165 mmol) was dissolved in anhydrous chloroform (200 mL), heated to 75° C. and treated with a solution of bromine (8.5 mL, 165 mmol) in anhydrous chloroform (40 mL) added dropwise over 5 minutes. After 3 hours the reaction was treated with additional bromine (1.7 mL, 33 mmol) in anhydrous chloroform (15 mL) and stirred at 75° C. After 2 hours, the reaction was cooled to room temperature and treated with dichloromethane (300 mL) and Na2S2O3 (100 mL, saturated aqueous solution). After mixing vigorously, the layers were separated and the organic layer was dried over MgSO4, filtered and concentrated under reduced pressure. The resulting yellow liquid was purified by vacuum distillation. Compound C.1 (22.3 g, 60%) was obtained as a colorless liquid. LC-MS ESI (neg.) m/e: 224.9 (M−H). 1H NMR (400 MHz) (CDCl3) □ 7.51 (d, J=6.9 Hz, 1H); 6.85 (d, J=9.2 Hz, 1H); 5.69 (s, 1H).

1. additionadded dropwise over 5 minutes
2. temperaturethe reaction was cooled to room temperature
3. additionAfter mixing vigorously
4. customthe layers were separated
5. dry with materialthe organic layer was dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. distillationThe resulting yellow liquid was purified by vacuum distillation
9. customCompound C.1 (22.3 g, 60%) was obtained as a colorless liquid

ORD-Eintrag

ord-c132b9ed6fca406cbee5bc8a4ec0269f

Quelldatensatz

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08183293B2