反应详情

To a stirred solution of 1-(tert-butoxycarbonyl)-4-(2,4-difluorophenoxy)-2-pyrrolidinylmethanol (500 mg, 1.52 mmol), methyl 4-hydroxybenzoate (277 mg, 1.82 mmol), and Ph3P (477 mg, 1.82 mmol) in THF (10 ml) was added DIAD (358 ul, 1.82 mmol), and the mixture was heated at reflux for 5 h. After cooling to room temperature, the mixture was concentrated in vacuo and the residue was chromatographed on silica gel with CHCl3-EtOAc (20:1) as eluent to give methyl 4-[1-(tert-butoxycarbonyl)-4-(2,4-difluorophenoxy)-2-pyrrolidinylmethoxy]benzoate (529 mg, 75%) as a colorless oil. 1H-NMR (CDCl3) δ1.46 (s, 9 H), 2.20-2.47 (m, 2 H), 3.64 (m, 2 H), 3.86 (s, 3 H), 4.07-4.43 (m, 3 H), 4.86 (m, 1 H), 6.74-6.87 (m, 3 H), 6.94 (d, 2 H, J=8.5 Hz), 7.95 (d, 2 H, J=8.5 Hz).

1. temperaturethe mixture was heated
2. temperatureat reflux for 5 h
3. concentrationthe mixture was concentrated in vacuo
4. customthe residue was chromatographed on silica gel with CHCl3-EtOAc (20:1) as eluent