Reaktion #63106

Reaktionsgleichung

3-(2,2,2-Trifluoroethyl)amino-5-amino-1,2,4-thiadiazole

tetrahydropyranyloxyacetamidine hydrochloride

sodium ethoxide

sodium

→

5-[2-(2,2,2-trifluoroethyl)guanidino]-3-hydroxymethyl-1,2,4-thiadiazole

Lösungsmittel

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthen heated
2. 2
   Temperaturunder reflux for 60 hours
3. 3
   SonstigeVolatile material was evaporated in vacuo
4. 4
   workup.STIRRINGthe residue was shaken with 2N hydrochloric acid (30 ml.) and ethyl acetate (30 ml.)
5. 5
   ExtraktionThe aqueous layer was further extracted with ethyl acetate (3×30 ml.)
6. 6
   ExtraktionThe basified mixture was extracted with ethyl acetate (6×30 ml.)
7. 7
   Trocknenthe combined extracts were dried (MgSO4)
8. 8
   Sonstigeevaporated in vacuo
9. 9
   Sonstigeto give the crude product as an oil
10. 10
    SonstigeIt would be purified by fractionation on a silica gel column
11. 11
    Wascheneluted with ethyl acetate

Vorschrift

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°.

Quelle