反应详情

Under a nitrogen atmosphere, a solution of 1.0 g of 1-[(5-acetoxy-4,6-di-t-butyl-2-methyl-2,3-dihydrobenzofuran-2-yl)methylideneamino]guanidine in 10 ml of tetrahydrofuran was added dropwise to a suspension of 0.98 g of lithium aluminum hydride in 20 ml of tetrahydrofuran at room temperature. After heating under reflux for 14 hours, a saturated aqueous ammonium chloride was added under ice-cooling, insoluble matters were filtered off on Celite and the filtrate was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate and then concentrated. The concentrate was purified by silica gel column chromatography eluting with chloroform containing 10% methanol to give 0.68 g of 1-[(4,6-di-t-butyl-5-hydroxy-2-methyl-2,3-dihydrobenzofuran-2-yl)methylamino]guanidine as a pale yellow oil (yield 76%).

1. temperatureAfter heating
2. temperatureunder reflux for 14 hours
3. temperaturecooling
4. filtrationinsoluble matters were filtered off on Celite
5. extractionthe filtrate was extracted with ethyl acetate
6. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
7. concentrationconcentrated
8. customThe concentrate was purified by silica gel column chromatography
9. washeluting with chloroform containing 10% methanol