2-Aminobenzenesulfonamide → Ethyl 3-[2-(aminosulfonyl)anilino]-3-oxopropanoate

Participants

Reaction Conditions

Reaction Steps

2-Amino-benzenesulfonamide (5 g, 29 mmol) was dissolved in N,N-dimethylacetamide (25 mL) and diethyl ether (25 mL). Ethyl-3-chloro-3-oxo-propionate (4.6 g, 30.45 mmol) was added into the above reaction solution. The reaction mixture was stirred at 25° C. for 3 h. The product started to precipitate and was collected by vacuum filtration. The solid was dissolved in ethyl acetate (200 mL) and extracted with water (200 mL). The aqueous layer was back-extracted with ethyl acetate (200 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo to afford the crude product, N-(2-sulfamoyl-phenyl)-malonamic acid ethyl ester, as a white solid, which was used in the next step without further purification. 1H NMR (400 MHz, DMSO-d6) δ: 1.23 (3H, t, J=7.0 Hz), 3.61 (2H, s), 4.14 (2H, quartet, J=7.0 Hz), 7.29-7.33 (1H, m), 7.53 (2H, bs), 7.56-7.60 (1H, m), 7.84-7.86 (1H, m), 7.97-7.99 (1H, m), 9.54 (1H, bs). LC-MS (ESI) calcd for C11H14N2O5S 286.06, found 287.1 [M+H+].

Provenance & Evidence