反应详情

A mixture of 2-(2,3-difluoro-6-nitrophenyl)ethanol (6.00 g, 29.6 mmol), as prepared in the preceding step, tert-butylamine (18.6 mL, 1.77 mmol), DMSO (30 mL), and toluene (5 mL) was heated at reflux for 16 hours. After cooling to ambient temperature the brown solution was poured into H2O (300 mL), and the deposited yellow crystals were filtered and washed with H2O twice. The yellow solid was dissolved in CHCl3 (70 mL), dried over Na2SO4, concentrated, and crystallized from hexane to give the title compound (4.70 g, 62% yield) as a yellow solid. 1H NMR (400 MHz, CDCl3) δ 7.92 (dd, J=9.3, 1.5 Hz, 1H), 6.79 (t, J=8.7 Hz, 1H), 4.69 (br s, 1H), 3.96 (dd, J=11.4, 5.9 Hz, 2H), 3.32 (dt, J=6.5, 3.1 Hz, 2H), 1.75 (t, J=5.3 Hz, 1 H), 1.46 (s, 9H).

1. temperaturewas heated
2. temperatureat reflux for 16 hours
3. filtrationthe deposited yellow crystals were filtered
4. washwashed with H2O twice
5. dissolutionThe yellow solid was dissolved in CHCl3 (70 mL)
6. dry with materialdried over Na2SO4
7. concentrationconcentrated
8. customcrystallized from hexane