Potassium Carbonate → N-[3-(1H-Pyrazol-1-yl)propyl]-2-nitrobenzenesulfonamide

Participants

Reaction Steps

A solution of 11.97 g (0.0519 mol) of o-nitrobenzenesulfonyl chloride in 90 ml of cyanomethane was added slowly over several minutes to a cold (7° C.) solution of 10.7 g (0.0540 mol) of N-(3-aminopropyl)-pyrazole in a 3:1 cyanomethane/water solution containing 16.6 g (0.12 mol) of potassium carbonate, under nitrogen. The resulting reaction solution was warmed to room temperature and allowed to react. When the reaction was complete, as determined by thin layer chromatography, the reaction solution was poured into approximately 450 ml of ethyl acetate. The resulting aqueous and organic layers were separated and the organic layer was washed with both an aqueous potassium carbonate solution and an aqueous sodium chloride solution and then reduced to dryness under reduced pressure to provide an oil. This oil was purified using column chromatography (8000 ml of a gradient eluent of from 0 to 5% methanol in methylene chloride). The fractions containing the desired product were combined, reduced to dryness under reduced pressure and then recrystallized from a 1:2 ethyl acetate/diethyl ether solution to provide 13.97 g of the desired subtitled intermediate (m.p. 105°109° C.).

Provenance & Evidence