反应详情

4-Amino-2-bromoanisole (4.7 g) was suspended in triethylorthoformate (50 ml), trifluoroacetic acid (1.8 ml) was added, and the reaction was heated at reflux for 36 hrs. The triethylorthoformate was removed in vacuo to afford a brown oil, which was dissolved in acetic acid (25 ml), sodium azide (2.25 g) was added and the mixture was heated for 4 hrs. The solvent was removed in vacuo and the residue dispersed between ethyl acetate and saturated sodium hydrogen carbonate. The organic layer was washed with water, brine, dried (MgSO4) and the solvent removed. Purification on flash silica eluting with 100% dichloromethane→0.25%→0.5%→0.75% methanol in dichloromethane afforded the title compound (4 g) as a brown solid. 1H NMR (250 MHz, DMSO) δ 4.06 (3H, s), 7.48 (1H, d, J=8.9) 8.03 (1H, dd, J=8.9, 2.7), 8.31 (1H, d, J=2.5), 10.15 (1H, s).

1. temperaturethe reaction was heated
2. temperatureat reflux for 36 hrs
3. customThe triethylorthoformate was removed in vacuo
4. customto afford a brown oil, which
5. temperaturethe mixture was heated for 4 hrs
6. customThe solvent was removed in vacuo
7. additionthe residue dispersed between ethyl acetate and saturated sodium hydrogen carbonate
8. washThe organic layer was washed with water, brine
9. dry with materialdried (MgSO4)
10. customthe solvent removed
11. customPurification on flash silica eluting with 100% dichloromethane→0.25%→0.5%→0.75% methanol in dichloromethane