Chloroform → HCID 10616642, compound

Participants

Reaction Steps

Under an argon atmosphere, 2-amino-3-benzyl-5-(4-methoxyphenyl)pyrazine (c-11) (prepared by the method described in Adamczyk, M. et al., Org. Prep. Proced. Int., 33, 477-485 (2001)) (199 mg, 681 μmol) was dissolved in anhydrous pyridine (1.4 mL) and chloroform (4 mL) and cooled to 0° C. To this was added acetyl chloride (365 μL, 5.13 mmol) and stirred for an hour after warming to room temperature. To this was added saturated aqueous solution of sodium bicarbonate to stop the reaction, and extracted 3 times with dichloromethane. The organic layer was washed with saturated aqueous solution of sodium sulfate and dried over anhydrous sodium sulfate. After removing anhydrous sodium sulfate by filtration, the filtrate was concentrated under reduced pressure with a rotary evaporator. The residue was recrystallized from methanol to give 2-acetylamino-3-benzyl-5-(4-methoxyphenyl)pyrazine (c-24) as a colorless solid (74.6 mg, 32.9%). Rf=0.14 (n-hexane/ethyl acetate=3/2). UV (MeOH) λmax (log ε) 329.5 (4.18), 293 (4.18), 274 (4.16). UV (pH 7.4 PB) λmax (log ε) 328 (4.11), 289.5 (4.01), 270.5 (4.05). 1H NMR (400 MHz, DMSO-d6) δ 2.04 (s, 3H), 3.81 (s, 3H), 4.15 (s, 2H), 7.02-7.08 (AA′BB′, 2H), 7.15-7.22 (m, 3H), 7.23-7.29 (m, 2H), 8.00-8.05 (AA′BB′, 2H), 8.87 (s, 1H), 10.25 (s, 1H). IR (KBr, cm−1) 698, 744, 833, 1032, 1157, 1175, 1213, 1256, 1285, 1327, 1368, 1416, 1450, 1499, 1543, 1587, 1609, 1670, 3258. HRMS (FAB+) m/z 334.1557 (M+H, C20H20N3O2 requires 334.1556).

Provenance & Evidence