Chloroacetonitrile → 2-Ethoxy-4-hydroxythiazole-5-carbonitrile

22.8 g of chloroacetonitrile were added dropwise with stirring at room temperature to a suspension of 61.5 g of the potassium salt of ethyl N-carbethoxy-thiocarbamate [described by Guha et al, Indian Chem. Soc., Vol. 6 (1929), p. 570] in one liter of methanol and after stirring the mixture for 2 hours, 30 g of triethylamine were added thereto. The mixture was stirred for another 48 hours and was then refluxed for 2 hours and filtered. The filtrate was concentrated to dryness and the residue was added to sodium hydroxide solution. The resulting solution was washed with ethyl ether, acidified with hydrochloric acid and extracted with ethyl ether. The extracts were dried and evaporated to dryness and the residue was crystallized from petroleum ether to obtain 26.4 g of 5-cyano-4-hydroxy-2-ethoxy-thiazole melting at 132°C.

1. stirringThe mixture was stirred for another 48 hours
2. temperaturewas then refluxed for 2 hours
3. filtrationfiltered
4. concentrationThe filtrate was concentrated to dryness
5. additionthe residue was added to sodium hydroxide solution
6. washThe resulting solution was washed with ethyl ether
7. extractionextracted with ethyl ether
8. customThe extracts were dried
9. customevaporated to dryness
10. customthe residue was crystallized from petroleum ether

ORD record

ord-aa30dbd7d66042cb93b7310e3bb5c8b4

Source dataset

uspto-grants-1977_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04020076