Preparation of N-acyl sulfonamides (2a-j), (3a-m), (5a-f) and cyclic imides (3n-r)Under nitrogen atmosphere, a mixture of sulfonamide (1 mmol), acylating agent (2 mmol) and Cs 5 HP 2 W 18 O 62 catalyst (5 mmol %) in water (2 mL), was stirred at room temperature to obtain (2a-j), (3a-m), (5a-f) and under reflux for (3n-r). Reaction was monitored by TLC. After completion of the reaction, the catalyst was removed by filtration. The filtrate was washed by water (10 mL) and extracted with EtOAc (3x15 mL). The combined organic layers were dried over anhydrous Na 2 SO 4 , then the solvent was evaporated in vacuum, and the crude compound was purified by flash chromatography (Merck silica gel 60 H, CH 2 Cl 2 /MeOH, 9:1) to afford the corresponding products.. NMR data of N-acyl sulfonamide derivatives (2a-j) N-(N-butylsulfamoyl)acetamide (2a)

An efficient and convenient protocol for the one-pot synthesis of new benzothiazoles bearing sulfonamide or cyclic imide moieties using Cesium salt of Wells-Dawson heteropolyacid (Cs 5 HP 2 W 18 O 62 ) as solid catalyst and water as solvent under ultrasound irradiation was reported. The reaction speed was remarkably catalyzed with the aid of ultrasound irradiation. Moreover, this approach prepares multiple other benefits such as operational ease, higher yields, and energy performance.

A simple and efficient preparation of novel series of mono-and bis-pyrrolidine-2,5-diones containing sulfonamide moiety was described. The strategy involved sequential one-pot sulfonylation-nucleophilic substitution procedure and was found effective under ultrasound activation and used for the first time. This approach allows the synthesis of products in good to excellent yields in short reaction time.

No abstract