Sulfuric Acid → 6-((6-bromo-1H-[1,2,3]triazolo[4,5-b]pyrazin-1-yl)methyl)quinoline

Participants

Reaction Steps

To a 6° C. mixture of 6-bromo-N2-(quinolin-6-ylmethyl)pyrazine-2,3-diamine (16 g, 48 mmol), AcOH (97 mL) and H2O (97 mL) was added NaNO2 (4.0 g, 58 mmol) in H2O (12 mL) dropwise over 15 min. After 1.5 hours, a 1:1 mixture of concentrated sulfuric acid and water (6 mL) was added dropwise. After 1.5 hours, NaNO2 (0.5 g, 7 mmol) in H2O (2 mL) and a 1:1 mixture of concentrated sulfuric acid and water (5 mL) were added. The reaction was allowed to warm to room temperature overnight. The reaction was re-cooled in an ice bath and over a period of 1.5 hours, a 1:1 mixture of concentrated sulfuric acid and water (30 mL) and NaNO2 (1.5 g, 22 mmol) in H2O (5 mL) was added. Aqueous 3.75 M NaOH (210 mL) was added dropwise and the resulting suspension was filtered. The precipitate was washed sequentially with water and ether, then suspended in dichloromethane:ethanol (1:1) and filtered. The filtrate was washed sequentially with 1M aqueous Na2CO3 and brine, dried over Na2SO4, filtered and concentrated by rotary evaporation to afford 6-((6-bromo-1H-[1,2,3]triazolo[4,5-b]pyrazin-1-yl)methyl)quinoline (9.6 g, 58%).

Provenance & Evidence