N-bromobutanimide → Ethyl 1-(5-bromo-8-methoxy-[1,2,4]triazolo[1,5-a]pyridin-2-yl)cyclopropanecarboxylate

関与物質

反応手順

To a stirred solution of 1-(8-methoxy-[1, 2, 4]triazolo[1,5-a]pyridine-2-yl)-cyclopropanecarboxylic acid ethyl ester (25 g, 95.7 mmol) in acetonitrile (300 mL) at RT, N-bromosuccinimide (34 g, 191.5 mmol) was added portion wise. After addition the reaction mixture was stirred at RT for 6 hours. The reaction mixture was diluted with EtOAc (600 mL), washed with water (100 mL×2), brine (50 mL), dried over anhydrous Na2SO4, filtered and concentrated. The crude was purified by silica gel column chromatography (0 to 10% EtOAc in dichloromethane as eluent) to afford the title compound (25 g, 77%, colorless solid). 1H NMR (400 MHz, DMSO): δ=7.44 (d, J=8.4 Hz; 1H), 7.07 (d, J=8 Hz; 1H), 4.13-4.08 (m, 2H), 3.97 (s, 3H), 1.60-1.57 (m, 2H), 1.48-1.45 (m, 2H), 1.13 (t, J=7.4 Hz; 3H) ppm.

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