Acetic Anhydride → 1-(2,4-Dihydroxy-3-nitrophenyl)ethan-1-one

Temperature

100 °C

2-Nitrobenzene-1,3-diol (24.5 g) was added portionwise over 15 min to a vigorously stirred solution of aluminium chloride (46.3 g) in nitrobenzene (325 mL). Acetic anhydride (15.65 mL) was then added dropwise to the mixture over a further 15 min and the mixture then heated at 100° C. for 5 h. The reaction was cooled to ambient temperature and carefully quenched with ice cold 2M hydrochloric acid (300 mL). The mixture was extracted with ether (2×500 mL) and the combined ether extracts then extracted with 2M aqueous sodium hydroxide (2×400 mL). The combined basic extracts were washed with ether (4×500 mL) and then acidified to pH 1 with 2M hydrochloric acid (700 mL). The resulting precipitate was filtered off, washed with water, and dried under vacuum at 40° C. to afford the subtitled compound as a yellow/brown solid (29.5 g). 1H NMR (400 MHz, DMSO-d6) δ 13.32 (s, 1H), 12.31 (s, 1H), 7.98 (d, J=9.2 Hz, 1H), 6.63 (d, J=28.2 Hz, 1H), 2.59 (s, 3H).

1. temperatureThe reaction was cooled to ambient temperature
2. customcarefully quenched with ice cold 2M hydrochloric acid (300 mL)
3. extractionThe mixture was extracted with ether (2×500 mL)
4. extractionthe combined ether extracts then extracted with 2M aqueous sodium hydroxide (2×400 mL)
5. washThe combined basic extracts were washed with ether (4×500 mL)
6. filtrationThe resulting precipitate was filtered off
7. washwashed with water
8. customdried under vacuum at 40° C.

ORD record

ord-45c6868cd1254a5f8195059e4be4386e

Source dataset

uspto-grants-2011_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08017602B2