反应详情

A solution of 2-amino-6-chloropyrazine (1 g.) in warm acetonitrile (15 ml.) was cooled to room temperature. Trifluoroethylisothiocyanate (1.6 g.) was added and the mixture stirred overnight. Further trifluoroethylisothiocyanate (1.6 g.) was added, and the mixture warmed gently on a steam bath for 2 hours, then heated under reflux for 2 hours. The mixture was allowed to cool and evaporated to dryness to yield a brown solid. This was washed with water, 2N HCl solution, water again, and sucked dry. Recrystallisation from boiling toluene diluted with petroleum ether (b.p. 60°-80°) yielded colourless needles (0.77 g.) of 2-[3-(2,2,2-trifluoroethyl)thioureido]-6-chloropyrazine m.p. 170°-172°.

1. temperaturethe mixture warmed gently on a steam bath for 2 hours
2. temperatureheated
3. temperatureunder reflux for 2 hours
4. temperatureto cool
5. customevaporated to dryness
6. customto yield a brown solid
7. washThis was washed with water, 2N HCl solution, water again
8. customsucked dry
9. customRecrystallisation
10. additiondiluted with petroleum ether (b.p. 60°-80°)