Toluene → Methyl 4-methyl-3-(4-sulfamoylphenyl)thiophene-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of methyl 3-bromo-4-methylthiophene-2-carboxylate (compound 7a, 9.0 g, 38.0 mmol) in ethanol: toluene (100:30 ml) in sealed tube, (4-sulfamoylphenyl)boronic acid (8.46 g, 42.0 mmol) and potassium carbonate (10.57 g, 76.0 mmol) were added under a nitrogen atmosphere at room temperature (about 25° C.). Nitrogen gas was purged to this suspension for further 15 minute at room temperature (about 25° C.) and tetrakis(triphenyl phosphine)palladium(0) (2.21 g, 1.9 mmol) was added at 25° C. and sealed tube was closed. The reaction mixture was stirred at 105° C. for 15 hr and the progress of the reaction was monitored by TLC. Reaction mixture was filtered and washed with ethyl acetate (2×100 ml). Organic layer was concentrated under reduced pressure to obtain crude product as semi-solid (11.2 g); which was purified by column chromatography over silica gel (100-200 mesh) using 50% ethyl acetate in hexanes as an eluent to obtain the title compound (20% ethyl ester as trans esterified product was observed) (8.8 g, 70.70%).

Provenance & Evidence