Diisopropylethylamine → HCID 118080010, compound

Participants

Reaction Conditions

Reaction Steps

N,N-Diisopropylethylamine (0.486 mL, 2.79 mmol) was added to a solution of (S)-1-(6-bromo-2-methyl-3,4-dihydroquinoxaline-1(2H)-yl)-2,2,2-trifluoroethanone (0.300 g, 0.928 mmol) and cyclopentyl chloroformate (0.144 mL, 1.114 mmol) in 1,2-dichloroethane (6.0 mL), and the mixture stirred at 50° C. for 3 days. Additional N,N-diisopropylethylamine (0.486 mL, 2.79 mmol) and cyclopentyl chloroformate (0.28 mL, 2.22 mmol) were added, and the mixture stirred at 50° C. for 16 h. The reaction mixture was concentrated to afford an off-white solid. This material was purified via column chromatography on silica gel (Biotage 25 g column, gradient elution with 0-25% ethyl acetate-hexane) to afford (S)-cyclopentyl 7-bromo-3-methyl-4-(2,2,2-trifluoroacetyl)-3,4-dihydroquinoxaline-1(2H)-carboxylate (0.390 g, 97%) as a yellow oil. MS (ESI, pos. ion) m/z 435, 437 [M+1]+.

Provenance & Evidence