Propylenediamine → 2-(1,3-Dimethyl-4-nitropyrazol-5-yl)-4-methylimidazoline

Participants

Reaction Conditions

Reaction Steps

p-Toluenesulfonic acid monohydrate (15.2 g, 0.08 mol) is added in portions with stirring to 6 g (0.08 mol) of 1,2-diaminopropane under nitrogen. To the resulting melt (ca 100° C.) is added in portions 12.6 g (0.076 mol) of 5-cyano-1,3-dimethyl-4-nitropyrazole (mp 93° C.); the mixture is stirred and heated to 120° C. and 25 ml of o-dichlorobenzene is added; stirring is continued at 120°-130° for 0.5 hours then at 160° C. for three hours. The cooled mixture is extracted with 75 ml of 3N HCl. The aqueous extract is made strongly basic with a large excess of concentrated NH4OH and the mixture is extracted thoroughly with methylene dichloride. Evaporation of the extract gives 14.3 g (84%) of 2-(1,3-dimethyl-4-nitropyrazol-5-yl)-4-methylimidazoline, mp 98°-101°.

Provenance & Evidence