反应详情

To a toluene (50 ml) solution of the compound of Example 38C (4.0 g, 20.4 mmol), Co(TPP) (411 mg, 0.61 mmol) and 1-methyl-1H-imidazole (5.0 g, 61.2 mmol), ethyl diazoacetate (3.5 g, 30.6 mmol) was added and the mixture was stirred for 5 minutes at room temperature followed by additional stirring for 2 hours at 80° C. Then, evaporation and purification by silica gel column chromatography, eluting with gradually from hexane to hexane/EtOAc (20:1), gave ethyl 2-(4-tert-butyl-3,5-difluorophenyl)cyclopropanecarboxylate (4.4 g, 76%, trans). To a THF (5 ml) solution of ethyl 2-(4-tert-butyl-3,5-difluorophenyl)cyclopropanecarboxylate (4.4 g, 15.5 mmol), 2M sodium hydroxide aqueous solution (30 ml) and MeOH (30 ml) were added and the mixture was stirred for 1 hour at room temperature. After the reaction was completed, the aqueous layer was extracted, and then acidified with 2M HCl aqueous solution and the whole was extracted with EtOAc, followed by evaporation, to give the title compound (3.48 g, 88%) as white solids.

1. extractionthe aqueous layer was extracted
2. extractionthe whole was extracted with EtOAc
3. customfollowed by evaporation