Trifluoroacetic acid → 1,1-Diphenyltetrahydro-1H-oxazolo[3,4-a]pyrazin-3(5H)-one

Participants

Reaction Steps

To a solution of (1,1-dimethylethyl)tetrahydro-3-oxo-1,1-diphenyl-3H-oxazolo[3,4-a]pyrazine-7(1H)-carboxylate (2.3 g, 5.5 mmol) in dichloromethane (20 mL) was added trifluoroacetic acid (4 mL), and the mixture was stirred at room temperature for 2 hours. To the reaction solution was added an aqueous saturated sodium hydrogen carbonate solution (10 mL), and the resulting mixture was extracted with ethyl acetate. The extract was washed with water, and then concentrated under reduced pressure. The residue was crystallized from diisopropyl ether to obtain the title compound (1.6 g, yield 99%).

Provenance & Evidence