Sulfuryl chloride → 8-(2-Chloro-6-fluoro-3,5-dimethoxy-phenyl)-quinoxaline-5-carboxylic acid ethyl ester

Participants

Reaction Steps

Sulfuryl chloride (0.35 mL, 4.33 mmol, 1.1 equiv) in CH3CN (10 mL) was added dropwise to a cold (−30° C.) solution of 8-(2,6-difluoro-3,5-dimethoxy-phenyl)-quinoxaline-5-carboxylic acid ethyl ester (Step 143.1) (1.4 g, 3.93 mmol) in CH3CN (40 mL). The reaction mixture was quenched by addition of a saturated solution of NaHCO3, allowed to warm to rt and concentrated. The residue was diluted in EtOAc and a saturated solution of NaHCO3. The aqueous phase was separated and extracted with EtOAc. The combined organic layers were washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue was purified by silica gel column chromatography (Hex/EtOAc, 3:2) to provide 1.27 g of the title compound as a white solid. Title compound: ESI-MS: 391.1 [M+H]+; tR=4.71 min (System 1); TLC: Rf=0.12 (Hex/EtOAc, 3:2).

Provenance & Evidence