Carbonic Acid → 5-Chloro-3-(2-chloro-5-fluorophenyl)-2-methylquinoxaline

Participants

Reaction Conditions

Reaction Steps

A mixture of 3,5-dichloro-2-methylquinoxaline (Prepared in Example 85, 1.0000 g, 4.693 mmol), 2-chloro-5-fluorophenylboronic acid (0.9002 g, 5.163 mmol), tetrakis(triphenylphosphine)palladium (0.2712 g, 0.2347 mmol), and sodium carbonate anhydrous (2.487 g, 23.47 mmol) in acetonitrile-water (3:1) (47.00 mL) was stirred at 100° C. After 3 hs, the mixture was cooled to room temperature and partitioned between EtOAc (100 mL) and water (100 mL). The organic layer was washed with brine (50 mL×2), dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography on a 80 g of Redi-Sep™ column using 0 to 50% gradient of EtOAc in hexane over 25 min and then 50% isocratic of EtOAc for 10 min as eluent to give 5-chloro-3-(2-chloro-5-fluorophenyl)-2-methylquinoxaline as a red syrupy solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 8.09 (1H, dd, J=8.4, 1.4 Hz), 8.03 (1H, dd, J=7.6, 1.4 Hz), 7.88 (1H, dd, J=8.4, 7.6 Hz), 7.75 (1H, dd, J=9.0, 5.1 Hz), 7.61 (1H, dd, J=8.6, 3.1 Hz), 7.46-7.53 (1H, m), 2.54 (3H, s); LC-MS (ESI) m/z 307.0 [M+H]+.

Provenance & Evidence