反应详情

Diisopropyl azodicarboxylate (1.1 ml, 5.5 mmol) was added dropwise to a solution of 2-(t-butoxycarbonylamino)ethanol (850 μl, 5.5 mmol), 3-hydroxyisoxazole (Method 75; 425 mg, 5 mmol) and triphenylphosphine (1.44 g, 5.5 mmol) in THF (20 ml) and the mixture was stirred at ambient temperature for 18 hours. The solvent was evaporated and the residue purified by flash chromatography on silica gel eluting with iso-hexane:EtOAc (100:0 increasing in polarity to 4:1) to give the title compound (506 mg, 44%) as a white solid. NMR 1.43 (s, 9H), 3.56 (m, 2H), 4.32 (m, 2H), 4.90 (s, 1H), 5.98 (s, 1H), 8.16 (s, 1H); m/z 229.

1. customThe solvent was evaporated
2. customthe residue purified by flash chromatography on silica gel eluting with iso-hexane:EtOAc (100:0 increasing in polarity to 4:1)