反应详情

温度

75 °C

0.59 g of magnesium turnings in 3 ml of diethyl ether are activated with 1 drop of bromine, and a solution of 1.5 ml of methyl iodide in 5.5 ml of diethyl ether is added dropwise with stirring. When the exothermic reaction has subsided, the mixture is heated and kept for a further 1.5 hours at bath temperature 55° C. The resulting solution is added dropwise under a nitrogen atmosphere and with stirring at -10° C. to the initially introduced solution of 4.9 g of N-methyl-N-methoxybenzo-1,2,3-thiadiazole-7-carboxamide in 150 ml of absolute tetrahydrofuran. After stirring has been continued for 1 hour at -10° C., the mixture is heated and refluxed at bath temperature 75° C. for 6 hours. The reaction mixture is then cooled, poured into ice-water, acidified with 2 N hydrochloric acid and extracted several times using ethyl acetate. The extracts are washed with water, dried over sodium sulfate and evaporated. The residue is purified on silica gel (CHCl3), giving the title compound of m.p. 126°-127° C.

1. customWhen the exothermic reaction
2. temperaturethe mixture is heated
3. customtemperature 55° C
4. additionThe resulting solution is added dropwise under a nitrogen atmosphere
5. stirringAfter stirring
6. waithas been continued for 1 hour at -10° C.
7. temperaturethe mixture is heated
8. temperatureThe reaction mixture is then cooled
9. extractionextracted several times
10. washThe extracts are washed with water
11. dry with materialdried over sodium sulfate
12. customevaporated
13. customThe residue is purified on silica gel (CHCl3)