Toluene → HCID 19931881, compound

Participants

Reaction Conditions

Reaction Steps

2 ml of a 1.98M solution of phosgene in toluene were added to a solution of 200 mg of 3-(2,4,6-trimethylphenylsulfonyl)pyrazole [prepared as described in step (2) above] in 1 ml of toluene, and the resulting solution was heated at 60° C. for 1 hour. The mixture was concentrated by evaporation under reduced pressure, and then 97 mg of triethylamine and 89 mg of diisopropylamine were added, in that order, to the oily residue. The reaction mixture was then stirred at ambient temperature for 20 minutes, after which it was diluted with diethyl ether. The ethereal solution was washed with 1N aqueous hydrochloric acid, with an aqueous solution of sodium hydrogencarbonate and with water, in that order, and was then dried over anhydrous sodium sulfate. The solvent was removed by distillation under reduced pressure, and the resulting residue was purified by column chromatography through silica gel, eluted with a 6:1 by volume mixture of hexane and ethyl acetate, to afford 268 mg (yield 89%) of the title compound, melting at 64°-65° C.

Provenance & Evidence