反应详情

3-(2,2,2-Trifluoroethyl)amino-5-amino-1,2,4-thiadiazole (2.0 g.) and tetrahydropyranyloxyacetamidine hydrochloride (2.0 g.) was added to a solution of sodium ethoxide prepared from sodium (0.46 g.) and alcohol (50 ml.). The resulting mixture was stirred at 20° for 4 hours then heated under reflux for 60 hours. Volatile material was evaporated in vacuo and the residue was shaken with 2N hydrochloric acid (30 ml.) and ethyl acetate (30 ml.). The aqueous layer was further extracted with ethyl acetate (3×30 ml.) then the pH was adjusted to 10 with 2N sodium hydroxide. The basified mixture was extracted with ethyl acetate (6×30 ml.) and the combined extracts were dried (MgSO4) and evaporated in vacuo to give the crude product as an oil. It would be purified by fractionation on a silica gel column eluted with ethyl acetate to give 5-[2-(2,2,2-trifluoroethyl)guanidino]-3-hydroxymethyl-1,2,4-thiadiazole, m.p. 123°-125°.

1. temperaturethen heated
2. temperatureunder reflux for 60 hours
3. customVolatile material was evaporated in vacuo
4. stirringthe residue was shaken with 2N hydrochloric acid (30 ml.) and ethyl acetate (30 ml.)
5. extractionThe aqueous layer was further extracted with ethyl acetate (3×30 ml.)
6. extractionThe basified mixture was extracted with ethyl acetate (6×30 ml.)
7. dry with materialthe combined extracts were dried (MgSO4)
8. customevaporated in vacuo
9. customto give the crude product as an oil
10. customIt would be purified by fractionation on a silica gel column
11. washeluted with ethyl acetate