Trifluoroacetic acid → (+/-) 2-((3-((3R,4R)-4-amino-3-((tert-butyldimethylsilyl)oxy)piperidin-1-yl)-2-chloro-5-cyanophenyl)amino)-4-(cyclopropylamino)imidazo[2,1-f][1,2,4]triazine-7-carbonitrile

Participants

Reaction Conditions

Reaction Steps

TFA (25% in 1,2-dichloroethane, 4 mL, 12.98 mmol) was added to a solution of (+/−)-tert-butyl ((3R,4R)-3-((tert-butyldimethylsilyl)oxy)-1-(2-chloro-5-cyano-3-((7-cyano-4-(cyclopropyl(4-methoxybenzyl)amino)imidazo[2,1-f][1,2,4]triazin-2-yl)amino)phenyl)piperidin-4-yl)carbamate (270 mg, 0.338 mmol) and anisole (0.148 mL, 1.351 mmol) in 1,2-dichloroethane (2 mL) and the resulting solution was heated at 30° C. overnight The reaction mixture was diluted with dichloromethane and washed with cold saturated sodium bicarbonate/1N aqueous sodium hydroxide (pH 10), the layers were separated and aqueous layer was extracted with dichloromethane/methanol (4/1) two more times. The combined organic layers were dried over magnesium sulfate, filtered and concentrated in vacuo, the crude product was purified by flash chromatography on silica gel using an automated ISCO system (40 g column, eluting with 1-7% methanol/dichloromethane to afford (+/−)-2-((3-((3R,4R)-4-amino-3-((tert-butyldimethylsilyl)oxy)piperidin-1-yl)-2-chloro-5-cyanophenyl)amino)-4-(cyclopropylamino)imidazo[2,1-f][1,2,4]triazine-7-carbonitrile (119 mg,) and then 6-16% 2 N ammonia in methanol/dichloromethane to give (+/−)-2-((3-((3R,4R)-4-amino-3-hydroxypiperidin-1-yl)-2-chloro-5-cyanophenyl)amino)-4-(cyclopropylamino)imidazo[2,1-f][1,2,4]triazine-7-carbonitrile (8 mg,).

Provenance & Evidence