反应详情

Benzyl chloroformate (3.8 mL, 26.6 mmol) was added to a solution of 3-(N-carbobenzyloxy-3-fluoroanilin-4-yl)-3-hydroxy-1-(1,1-diphenylmethyl)azetidine (Example 81, Step 2, 1.60 g, 3.32 mmol) in benzene (30 mL) and then heated under reflux under nitrogen for 2 hr. The benzene was evaporated and the residue chromatographed over silica gel (150 g, 40-60 μm) eluting with 20-60% ethyl acetate-hexane. The title compound was obtained as a white foam. 1H NMR δ (CDCl3): 3.32, 4.19, 4.42, 5.08, 5.17, 6.98, 7.11, 7.19, 7.24-7.43.

1. temperatureheated
2. temperatureunder reflux under nitrogen for 2 hr
3. customThe benzene was evaporated
4. customthe residue chromatographed over silica gel (150 g, 40-60 μm)
5. washeluting with 20-60% ethyl acetate-hexane