Acetic Acid → 5-[(R)-2-amino-1-(tert-butyldimethylsilanyloxy)ethyl]-8-hydroxy-1H-quinolin-2-one acetate

Participants

Reaction Steps

8-Benzyloxy-5-[(R)-2-(N-benzylamino)-1-(tert-butyldimethylsilanyloxy)ethyl]-1H-quinolin-2-one (100 g, 194 mmol) and acetic acid (17.5 mL, 291 mmol) were dissolved in methanol (1 L). The clear solution was purged with nitrogen and then palladium hydroxide on carbon (20 g, 20 wt. % Pd (dry basis), wet (about 50% water)) was added. Hydrogen gas was bubbled through the stirred solution at room temperature for 6 hours during which time a thick slurry developed. The reaction mixture was then purged with nitrogen and methanol (1 L) was added. The resulting mixture was stirred for about 30 minutes (to dissolve the product) and then the mixture was filtered through a pad of Celite. The filterate was concentrated under reduced pressure to a volume of about 500 mL and, to the resulting slurry, was added ethanol (500 mL). The resulting mixture was again concentrated under reduced pressure to a volume of about 500 mL and the resulting precipitate was collected by filtration and dried to provide the title compound as a yellow-white solid (65 g, 85% yield, >98% purity).

Provenance & Evidence