反应详情

A solution of 3-(5-chloro-6-methoxypyridin-2-yl)prop-2-yn-1-ol (3.0 g) in tetrahydrofuran (50 mL) was stirred under ice-cooling in a nitrogen atmosphere, during which a solution of sodium bis(2-methoxyethoxy)aluminum hydride (Red-Al(R)) in toluene (3.6 M, 7 mL) was added dropwise thereto. The mixture was stirred at room temperature for one hour. The reaction solution was cooled to an external temperature of −78° C. A solution of N-iodosuccinimide (6.2 g) in tetrahydrofuran (30 mL) was added dropwise and then the mixture was stirred at an external temperature of −78° C. for one hour. 1 M hydrochloric acid was added to the reaction solution, followed by extraction with ethyl acetate. The organic layer was sequentially washed with a 10% sodium thiosulfate solution and brine and dried over sodium sulfate. After filtration, the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=9:1→5:5) to give the title compound as a brown powder (3.79 g, 76%).

1. additionwas added dropwise
2. temperatureThe reaction solution was cooled to an external temperature of −78° C
3. stirringthe mixture was stirred at an external temperature of −78° C. for one hour
4. extractionfollowed by extraction with ethyl acetate
5. washThe organic layer was sequentially washed with a 10% sodium thiosulfate solution and brine
6. dry with materialdried over sodium sulfate
7. filtrationAfter filtration
8. customthe solvent was evaporated under reduced pressure
9. customThe residue was purified by silica gel column chromatography (hexane:ethyl acetate=9:1→5:5)