Potassium Carbonate → 2-(4-bromo-2-formylphenoxy)propanoic acid

A solution of 5-bromo-2-hydroxybenzaldehyde (4.97 mmol) in acetonitrile (30 mL) was treated with potassium carbonate (14.92 mmol) and ethyl 2-bromopropanoate (5.97 mmol). The resulting mixture was stirred at room temperature overnight. Analysis by LCMS indicated the formation of the desired intermediate ester, and the reaction mixture was concentrated to dryness in vacuo. The crude material was dissolved in a 3:1 methanol:water mixture (20 mL) and was heated to 50° C. with stirring. The reaction was then cooled to room temperature and was acidified to pH˜3 using 1N aq HCl. The methanol was removed in vacuo and the resulting aqueous suspension was diluted with water (100 mL). The solution was extracted with dichloromethane. The combined organic layers were washed with brine, dried over magnesium sulfate, filtered, and concentrated in vacuo. The resulting beige solid was used without further purification (1.38 grams, 80% yield). MS(ES)+ m/e 273/275 [M+H]+ (bromide isotope pattern).

1. concentrationthe reaction mixture was concentrated to dryness in vacuo
2. dissolutionThe crude material was dissolved in a 3:1 methanol
3. temperaturewater mixture (20 mL) and was heated to 50° C.
4. stirringwith stirring
5. temperatureThe reaction was then cooled to room temperature
6. customThe methanol was removed in vacuo
7. additionthe resulting aqueous suspension was diluted with water (100 mL)
8. extractionThe solution was extracted with dichloromethane
9. washThe combined organic layers were washed with brine
10. dry with materialdried over magnesium sulfate
11. filtrationfiltered
12. concentrationconcentrated in vacuo
13. customThe resulting beige solid was used without further purification (1.38 grams, 80% yield)

ORD record

ord-bff6c355f8e4498e8db640b9e392d023

Source dataset

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09340529B2