反应详情

温度

5 °C

A suspension of 9.65 g of 4-methyl-[1,2,3]thiadiazol-5-carboxylic acid in 70 ml of dichlormethane was cooled to 5° C. while stirring, treated with 0.15 g of 4-dimethylamino-pyridine and subsequently with 13.8 g of N,N'-dicyclohexyl-carbodiimide at such a rate that the internal temperature <10° C. could be maintained. After completion of the addition, the mixture was cooled to 5° C. and 8.92 g of phenethylamine were added at such a rate that the internal temperature of <37° C. could be maintained. After completion of the addition, the mixture was stirred for a further 1 h., then the precipitate was filtered off under suction, rinsed well with dichloromethane and the filtrate was evaporated. The residual yellow oil was subjected to chromatography on silica gel with hexane/ethyl acetate 50:50. There were obtained 15.66 g (92%) of 4-methyl-[1,2,3]thiadiazole-5-carboxylic acid phenethylamide as a colorless crystallizate of m.p. 64°-68° C. Recrystallization of a sample from tert.-butyl methyl ether gave colorless crystals of m.p. 64.5°-66° C.

1. temperaturecould be maintained
2. additionAfter completion of the addition
3. temperaturethe mixture was cooled to 5° C.
4. temperaturecould be maintained
5. additionAfter completion of the addition
6. stirringthe mixture was stirred for a further 1 h.
7. filtrationthe precipitate was filtered off under suction
8. washrinsed well with dichloromethane
9. customthe filtrate was evaporated