Water → 3-Bromo-5-fluoro-2-hydroxybenzaldehyde

1.0 g (5.24 mmol) of 2-bromo-4-fluorophenol is initially charged in 4 ml of TFA. Over a period of 20 min, 1.47 g (10.47 mmol) of hexamethylenetetramine are added a little at a time. The mixture is then heated under reflux for 28 h. At RT, 6 ml of water and 3 ml of 50% strength sulfuric acid are added. After 2 h at RT, the reaction mixture is extracted twice with in each case 30 ml of ethyl acetate. The combined organic phases are washed four times with 1N hydrochloric acid and once with water and then dried over magnesium sulfate. The crude product is reacted further without further purification.

1. temperatureThe mixture is then heated
2. temperatureunder reflux for 28 h
3. waitAfter 2 h at RT
4. extractionthe reaction mixture is extracted twice with in each case 30 ml of ethyl acetate
5. washThe combined organic phases are washed four times with 1N hydrochloric acid
6. dry with materialonce with water and then dried over magnesium sulfate
7. customThe crude product is reacted further without further purification

ORD-Eintrag

ord-dc6e313bd581481b9620679b2a7d3673

Quelldatensatz

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07732477B2