p-Toluenesulfonic acid → p-Toluenesulfonate

Participants

Reaction Steps

A mixture of 65 grams of N-(3-chloropropyl)-N'-(2,6-dimethylphenyl)urea, 350 ml. of acetonitrile, and 50 grams of propargylamine was refluxed for 19 hours. The reaction mixture was filtered and the filtrate was evaporated to dryness in vacuo. The residue was dissolved in chloroform and extracted with 250 ml. of 20% hydrochloric acid. The acid extract was cooled and made basic with 50% sodium hydroxide solution. The mixture was extracted with dichloromethane. After drying over magnesium sulfate, the dichloromethane was removed in vacuo to obtain a solid residue, m.p. 139°-143° C. The solid was treated with p-toluenesulfonic acid to obtain the salt. Recrystallization from ethanol-ether afforded N-(2,6-dimethylphenyl)-N'-[3-(2-propynylamino)propyl]urea, 4-methylbenzenesulfonate, m.p. 143°-144.5° C.

Provenance & Evidence