Hydrazine hydrate (1:1) → 2-(3-Aminopropyl)thiooxazole

Participants

Reaction Steps

Hydrazine hydrate (5.3 g.) was added carefully to a solution of 2-(3-phthalimidopropylthio)oxazole (10 g.) in ethanol (173 ml.) with stirring. The solution was then heated under reflux for 25 minutes. After cooling, and filtration from phthalhydrazide, the filtrate was concentrated under reduced pressure and the residue was re-evaporated with ethanol to yield crude 2-(3-aminopropylthio)oxazole which was washed twice with ether and dissolved in ethanol (60 ml.). Methyl isothiocyanate (2.54 g.) was added and the solution was heated under reflux for 30 minutes. Following cooling and filtration from insoluble material, the filtrate was concentrated to an oil which was chromatographed on a column of silica gel with ethyl acetate as eluant. The product obtained crystallised from ethanol-ether-n-hexane to give N-methyl-N'-[3-(2-oxazolyl)-thiopropyl]thiourea (2.4 g.), m.p. 43°-45°.

Provenance & Evidence