反应详情

A mixture of 50 parts of 2-thiazolamine, 76 parts of 3-acetyl-4,5-dihydro-2(3H)-furanone, 1.2 parts of concentrate hydrochloric acid and 270 parts of methylbenzene was stirred and refluxed for 2 hours using a water-separator. The reaction mixture was cooled and 340 parts of phosphoryl chloride were added at a temperature between 20° and 30° C. The whole was heated slowly to 100°-110° C. and stirring was continued for 2 hours at this temperature. The reaction mixture was evaporated and the residue was poured onto a mixture of crushed ice and ammonium hydroxide. The product was extracted with trichloromethane. The extract was dried, filtered and evaporated. The residue was purified by column-chromatography over silica gel using a mixture of trichloromethane and methanol (95:5 by volume) as eluent. The pure fractions were collected and the eluent was evaporated. The residue was crystallized from a mixture of 2-propanol and 1,1'-oxybisethane, yielding 36 parts of 6-(2-chloroethyl)- 7-methyl-5H-thiazolo[3,2-a]pyrimidin-5-one (intermediate 5).

1. temperaturerefluxed for 2 hours
2. temperatureThe reaction mixture was cooled
3. temperatureThe whole was heated slowly to 100°-110° C.
4. stirringstirring
5. customThe reaction mixture was evaporated
6. additionthe residue was poured onto a mixture of crushed ice and ammonium hydroxide
7. extractionThe product was extracted with trichloromethane
8. customThe extract was dried
9. filtrationfiltered
10. customevaporated
11. customThe residue was purified by column-chromatography over silica gel using
12. additiona mixture of trichloromethane and methanol (95:5 by volume) as eluent
13. customThe pure fractions were collected
14. customthe eluent was evaporated
15. customThe residue was crystallized from a mixture of 2-propanol and 1,1'-oxybisethane