反应详情

A solution of 15.8 g (77 mmol) of (R)-2-(2-hydroxy-1-methylethyl)-1H-isoindole-1,3(2H)-dione, 24.2 g (92 mmol) of triphenylphosphine and 10.0 g (77 mmol) of 2,5-difluorophenol was stirred while 18.2 mL (116 mmol) of diethylazodicarboxylate was added dropwise. After stirring at ambient temperature overnight, solvent was removed and the residue was dissolved in ethyl acetate. The ethyl acetate was washed with water and brine. Drying (MgSO4) and removal of solvent gave an oil which was chromatographed on silica gel to give 15.6 g of the title compound of Step C as an oil, 1H NMR (CDCl3) δ 1.55 (d, 3H), 4.25 (m, 1H), 4.8 (m, 1H), 6.55 (, 1H), 6.65 (m, 1H), 6.9 (m, 1H), 7.7 (m, 2H), 7.85 (m, 2H).

1. additionwas added dropwise
2. customsolvent was removed
3. dissolutionthe residue was dissolved in ethyl acetate
4. washThe ethyl acetate was washed with water and brine
5. customDrying
6. custom(MgSO4) and removal of solvent
7. customgave an oil which
8. customwas chromatographed on silica gel