Hydrochloric Acid → phenyl (S)-4-acetyl-3-methyl-7-(4-(piperazine-1-carbonyl)phenyl)-3,4-dihydroquinoxaline-1(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

A reaction vial was charged with (S)-tert-butyl 4-(4-(1-acetyl-2-methyl-1,2,3,4-tetrahydroquinoxalin-6-yl)benzoyl)piperazine-1-carboxylate (0.2 M in 1,2-dichloroethane, 100 μL, 0.02 mmol), N,N-diisopropylethyl amine (25 μL, 0.14 mmol), and phenyl chloroformate (6.23 mg, 0.04 mmol), and the mixture was shaken at 50° C. for 2 h. Methanol (50 μL) was added and the mixture was shaken at 50° C. for 10 min. HCl (4 M in dioxane, 0.075 mL, 0.30 mmol) was added and the reaction was shaken at 50° C. for 2 h. The mixture was concentrated and the residue was purified by mass triggered preparatory HPLC. The product-containing fractions were combined and concentrated in a Genevac to afford phenyl (S)-4-acetyl-3-methyl-7-(4-(piperazine-1-carbonyl)phenyl)-3,4-dihydroquinoxaline-1(2H)-carboxylate. MS (ESI, pos. ion) m/z 499.

Provenance & Evidence