反应详情

The mixture of 3-ethoxy-5-fluoro-4-hydroxybenzaldehyde (Intermediate 32) (160 mg, 0.87 mmol), 1,2-diphenyl-ethanone (170 mg, 0.87 mmol), urea (157 mg, 2.61 mmol), and concentrated HCl solution (0.2 mL) in ethanol (20 mL) was degassed and refluxed for 3 days under N2 protection. The solvent was removed under reduced pressure, and the residue was purified by preparative HPLC to give Compound 64 (30 mg, 10.6%). 1H NMR (DMSO-d6 300 MHz) δ 9.08 (s, br, 1H), 8.63 (s, 1H), 7.42 (s, 1H), 7.19-7.26 (m, 5H), 7.01-7.03 (m, 3H), 6.72-6.81 (m, 4H), 5.04 (d, J=2.7 Hz, 1H), 3.99 (q, J1=6.9 Hz, J2=9.0 Hz, 2H), 1.33 (t, J=6.9 Hz, 3H); MS (ESI): m/z 405.1 [M+1]+.

1. customwas degassed
2. temperaturerefluxed for 3 days under N2 protection
3. customThe solvent was removed under reduced pressure
4. customthe residue was purified by preparative HPLC