反应详情

To a solution of 5-allyl-4-(trimethylsilyl)-2,3-dihydrofuro[2,3-b]pyridine (9.00 g, 38.6 mmol) in tetrahydrofuran (300 mL) was added boron trifluoride diethyl ether complex (5.38 mL, 42.5 mmol) under ice-cooling, and the mixture was warmed to room temperature. A 9-borabicyclo[3.3.1]nonane tetrahydrofuran solution (0.4M, 241 mL, 96.4 mmol) was added. After stirring for 1 hr, N,N,N′,N′-tetramethylethylenediamine (3.20 mL, 21.2 mmol) was added, and a mixed solution of 30% aqueous hydrogen peroxide (100 mL) and 2.5M aqueous sodium hydroxide solution (100 mL) was further added. The mixture was extracted with ethyl acetate, and the extract was washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane=5/95→60/40) to give the title compound (6.64 g, yield 68%).

1. temperaturecooling
2. extractionThe mixture was extracted with ethyl acetate
3. washthe extract was washed with saturated brine
4. dry with materialdried over anhydrous sodium sulfate
5. customThe solvent was evaporated under reduced pressure
6. customThe residue was purified by silica gel column chromatography (ethyl acetate/hexane=5/95→60/40)