反应详情

To an ice-cooled 94 ml of 1.0 M diisobutylalminium hydride toluene solution was added dropwise 5.41 g of diethyl (3-bromobenzyl)malonate at 15° C. or less under argon flow. The mixture was stirred for 30 minutes under ice-cooling, warmed to room temperature and stirred for 2 hours. The reaction solution was ice-cooled, and 21 ml of methanol was added dropwise slowly, then 41 ml of 2 N hydrochloric acid was added dropwise. The mixture was stirred for 20 minutes at room temperature. The reaction solution was filtered to remove insolubles, extracted with ethyl acetate, washed with saturated sodium hydrogen carbonate, dried over anhydrous magnesium sulfate and concentrated. The residue was purified by silica gel column chromatography (Wakogel® C-200, chloroform: methanol=10:1) to provide 1.96 g of the objective compound as white crystals. M.p. 61-63° C.

1. temperaturecooling
2. stirringstirred for 2 hours
3. temperaturecooled
4. stirringThe mixture was stirred for 20 minutes at room temperature
5. filtrationThe reaction solution was filtered
6. customto remove insolubles
7. extractionextracted with ethyl acetate
8. washwashed with saturated sodium hydrogen carbonate
9. dry with materialdried over anhydrous magnesium sulfate
10. concentrationconcentrated
11. customThe residue was purified by silica gel column chromatography (Wakogel® C-200, chloroform: methanol=10:1)