反应详情

A suspension of N-(2-hydroxy-5-bromophenyl)-3-nitro-4-methoxybenzamide (5.24 g, 14.2 mmol) and toluenesulfonic acid monohydrate (5.36 g, 31.2 mmol) in toluene (100 ml) was heated to reflux overnight. The cooled reaction mixture was washed with saturated sodium hydrogen carbonate solution (care foaming) and the organic layer separated. The aqueous layer was extracted with ethyl acetate (2×50 ml) and the combined organic layers dried over sodium sulfate and the solvent removed under reduced pressure. The residue was triturated with ether, filtered and dried under vacuum to give the subtitle compound as a pale pink solid (4.51 g, 93%). 1H NMR (DMSO) δ 8.61(d, 1H), 8.42(dd, 1H), 8.05(d, 1H), 7.79(d, 1H), 7.61(m, 2H), 4.05(s, 3H). MS m/z 349.0 (M+H)+.

1. temperaturewas heated
2. temperatureto reflux overnight
3. customThe cooled reaction mixture
4. washwas washed with saturated sodium hydrogen carbonate solution (care foaming)
5. customthe organic layer separated
6. extractionThe aqueous layer was extracted with ethyl acetate (2×50 ml)
7. dry with materialthe combined organic layers dried over sodium sulfate
8. customthe solvent removed under reduced pressure
9. customThe residue was triturated with ether
10. filtrationfiltered
11. customdried under vacuum