Acetic Anhydride → 5-Bromo-3-methyl-1-benzofuran

Temperature

140 °C

A solution of [(2-acetyl-4-bromophenyl)oxy]acetic acid (1.648 mmol) in acetic acid (2.075 mL) was treated with sodium acetate (9.89 mmol) and acetic anhydride (21.42 mmol). The reaction solution was heated with stirring to 140° C. for 3.5 h. Analysis by LCMS showed a major product that did not ionize, and consumption of starting material. The mixture was diluted with water and ethyl acetate and was washed with 1N aq NaOH until the aqueous phase was basic (pH˜12). The mixture was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and concentrated to an oil in vacuo. No further purification was carried out. 1H NMR (400 MHz, chloroform-d) δ ppm 7.67 (d, J=1.77 Hz, 1H) 7.38-7.45 (m, 2H) 7.32-7.38 (m, 1H) 2.24 (d, J=1.26 Hz, 3H).

1. temperatureThe reaction solution was heated
2. customconsumption of starting material
3. additionThe mixture was diluted with water and ethyl acetate
4. washwas washed with 1N aq NaOH until the aqueous phase
5. extractionThe mixture was extracted with ethyl acetate
6. washThe combined organic layers were washed with brine
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated to an oil in vacuo
10. customNo further purification

ORD record

ord-506f06d9d6864c09b8c3688aa30504ef

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08802864B2