2-Bromothiophene → (E)-2-Thiophen-2-yl-ethenesulfonic acid 4-fluoro-2-methyl-benzoylamide

Participants

Reaction Steps

To a solution of 4-fluoro-2-methyl-benzoic acid (197 mg, 1.27 mmol) and (E)-2-thiophen-2-yl-ethenesulfonic acid amide (155 mg, 0.82 mmol) (which was prepared analogously to example 1-1 steps i) to ii) starting from 2-bromo-thiophene) in dichloromethane (5 mL) and N,N-dimethylformamide (DMF) (2 mL) is added 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide (EDCI) (277 mg, 1.45 mmol) and 4-(dimethylamino)-pyridine (DMAP) (172 mg, 1.41 mmol) at room temperature (RT). The mixture was stirred at RT for 24 h, and solvent removed under reduced pressure. The crude reaction mixture is partitioned between aq. 1M HCl (25 mL) and ethyl acetate (25 mL). The organic phase is separated and washed with aq. 1M HCl (2×25 mL), and then with sat. aq. K2CO3 solution (3×25 mL) and dried (sodium sulfate) and concentrated in vacuo. After flash chromatography (heptane/ethyl acetate 3:1 to 1:1) ((E)-2-Thiophen-2-yl-ethenesulfonic acid 4-fluoro-2-methyl-benzoylamide can be isolated as a white solid. Yield 65 mg (15%)

Provenance & Evidence