Aluminium lithium hydride → 2-(5-amino-7-bromo-3-chloro-5H-chromeno[2,3-c]pyridin-5-yl)ethanol
Reaction equation
[N:1]([C:4]1([CH2:20][C:21](OCC)=[O:22])[C:17]2[CH:16]=[C:15]([Cl:18])[N:14]=[CH:13][C:12]=2[O:11][C:10]2[C:5]1=[CH:6][C:7]([Br:19])=[CH:8][CH:9]=2)=[N+]=[N-].[H-].[H-].[H-].[H-].[Li+].[Al+3]>C1COCC1>[NH2:1][C:4]1([CH2:20][CH2:21][OH:22])[C:17]2[CH:16]=[C:15]([Cl:18])[N:14]=[CH:13][C:12]=2[O:11][C:10]2[C:5]1=[CH:6][C:7]([Br:19])=[CH:8][CH:9]=2Participants
4
Procedure
A solution of ethyl 2-(5-azido-7-bromo-3-chloro-5H-chromeno[2,3-c]pyridin-5-yl)acetate (40.82 g, 96 mmol) in THF (400 ml) was cooled to 0° C. under nitrogen atmosphere. A solution of LAH (1.0M solution in THF; 116 ml, 116 mmol) was added drop wise at 0° C. over a time period of 90 minutes. 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 20 minutes at RT. Celite was added to the reaction mixture and the suspension was filtered. The filtrate was concentrated under reduced pressure and the crude residue was purified by chromatography [1-2% (2M ammonia in MeOH)/DCM] to afford 2-(5-amino-7-bromo-3-chloro-5H-chromeno[2,3-c]pyridin-5-yl)ethanol (17.3 g, 48.6 mmol, 50.5% yield).