Water → Methyl 5-methyl-4-[methyl(2-thienylsulfonyl)amino]thiophene-2-carboxylate

Participants

Reaction Steps

To a solution of methyl 5-methyl-4-[(2-thienylsulfonyl)amino]thiophene-2-carboxylate (35.7 g) in N,N-dimethylformamide (200 mL) was slowly added sodium hydride (60%, oily, 5.2 g) at 0° C., and the mixture was stirred at room temperature for 30 min. Methyl iodide (8.0 mL) was added to the reaction mixture, and the mixture was stirred at room temperature for 1 hr. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried (MgSO4) and concentrated. The residue was subjected to silica gel column chromatography to give methyl 5-methyl-4-[methyl(2-thienylsulfonyl)amino]thiophene-2-carboxylate (37.5 g, yield 99%) as yellow crystals from a fraction eluted with ethyl acetate-hexane (1:3, volume ratio).

Provenance & Evidence