Potassium Carbonate → Methyl 4-[({[4-cyano-3-(4-nitrophenyl)isothiazol-5-yl]amino}carbonyl)amino]butanoate

Participants

Reaction Steps

A solution of 5-amino-3-(4-nitrophenyl)isothiazole-4-carbonitrile (25.0 g, 0.101 mol) in tetrahydrofuran (300 mL) dimethylsulfoxide (40 mL) at ambient temperature was treated with potassium carbonate (35.0 g, 0.25 mol). The resulting mixture was stirred at ambient temperature for 15 min. The reaction mixture was treated with 4-isocyanato-butyric acid methyl ester (21.8 g, 0.15 mol) at ambient temperature. The mixture was stirred at ambient temperature overnight. The reaction mixture was filtered through celite and filtrate concentrated in vacuo. The residue was dissolved EtOAc (600 mL) and washed with water and brine then dried (sodium sulfate), filtered, solvent concentrated in vacuo. The crude residue was purified by column chromatography (20% ethyl acetate in dichloromethane) to give the title compound as a light brown solid (31.5 g, 78%).

Provenance & Evidence