反应详情

A solution of ethyl 2-(5-azido-7-bromo-3-chloro-5H-chromeno[2,3-c]pyridin-5-yl)acetate (47 g, 111 mmol) in THF (600 ml) was cooled to 0° C. under nitrogen atmosphere. A solution of LAH (1.0M in THF; 133 ml, 133 mmol) was added drop wise at 0° C. Upon complete addition, the reaction mixture was warmed to RT and stirred for additional 10 minutes. The reaction mixture was quenched with sodium sulfate decahydrate (50 g) and stirred for 1 hour at room temperature. The suspension was filtered over celite. The filtrate was concentrated under reduced pressure and the crude residue was purified by recrystallization from cold DCM with heptane to afford 2-(5-amino-7-bromo-3-chloro-5H-chromeno[2,3-c]pyridin-5-yl)ethanol (16 g, 45.0 mmol, 40.6% yield).

1. additionUpon complete addition
2. customThe reaction mixture was quenched with sodium sulfate decahydrate (50 g)
3. stirringstirred for 1 hour at room temperature
4. filtrationThe suspension was filtered over celite
5. concentrationThe filtrate was concentrated under reduced pressure
6. customthe crude residue was purified by recrystallization from cold DCM with heptane