反应详情

A mixture of 2,2-difluoroethanol (0.178 mL, 2.82 mmol) and KOtBu (0.319 g, 2.70 mmol) in 10 mL THF was stirred for 5 min, then ethyl 2-fluoro-5-nitrobenzoate (0.500 g, 2.35 mmol) was added and it was stirred at rt overnight. Additional 60 μL 2,2-difluoroethanol and 110 mg KOtBu were added and it was stirred for 2 h. The mixture was diluted with H2O, concentrated i.vac. and extracted 2× with EtOAc. The combined organic layers were dried with Na2SO4 and concentrated to furnish the subtitle compound. Yield: 0.52 g (81%); TLC: Rf=0.85 (silica gel, DCM:EtOH 99:1).

1. stirringit was stirred at rt overnight
2. stirringit was stirred for 2 h
3. concentrationconcentrated i.vac
4. extractionand extracted 2× with EtOAc
5. dry with materialThe combined organic layers were dried with Na2SO4
6. concentrationconcentrated