反应详情

A solution of 4-bromo-2-nitrophenol (297, 1.00 g, 4.59 mmol) (scheme 65) in acetic anhydride (10 mL) was heated in a pressure vessel at 130-140° C. for 16 h. Most of the solvent was evaporated in vacuo and the resulting oil was kept in the freezer for 3 days. Crystallization occurred while thawing. The white crystals were suspended in a mixture of EtOAc/hexanes (9:1) and collected by filtration affording the title compound 328 (1.03 g, 87% yield). 1H NMR: (400 MHz, DMSO-d6) δ (ppm): 8.33 (d, J=2.3 Hz, 1H), 8.02 (dd, J=8.6, 2.3 Hz, 1H), 7.45 (d, J=8.6 Hz, 1H), 2.33 (s, 3H). LRMS: (m/z): 282.0/284.0 ((M+/M+2)+23).

1. customMost of the solvent was evaporated in vacuo
2. customCrystallization
3. additionThe white crystals were suspended in a mixture of EtOAc/hexanes (9:1)
4. filtrationcollected by filtration