반응 #1159088

반응 방정식

methyl 2-chloro-4-methyl-benzothiazole-5-carboxylate

potassium methoxide

→

methyl 4-methylbenzothiazol-2-one-5-carboxylate

수율 55.0%

용매

N-methylpyrrolidone

반응 조건

후처리

1. 1
   온도After cooling
2. 2
   여과the resulting precipitate was filtered off with suction
3. 3
   추출the aqueous solution was extracted three times with ethyl acetate
4. 4
   세척the combined organic phases were washed
5. 5
   기타dried
6. 6
   기타The solvent was removed under reduced pressure
7. 7
   기타the residue was purified by trituration with methylene chloride/n-hexane

실험 절차

A solution of 22.5 g (93 mmol) of methyl 2-chloro-4-methyl-benzothiazole-5-carboxylate in 360 ml of N-methylpyrrolidone was admixed with 13.6 g (186 mmol) of potassium methoxide and heated at 100° C. for 5 hours. After cooling, the resulting precipitate was filtered off with suction and the filtrate was admixed with water. The pH of the reaction solution was then adjusted to pH 1, the aqueous solution was extracted three times with ethyl acetate and the combined organic phases were washed and dried. The solvent was removed under reduced pressure and the residue was purified by trituration with methylene chloride/n-hexane. This gave, in a yield of 55%, 11.38 g (51 mmol) of methyl 4-methylbenzothiazol-2-one-5-carboxylate of m.p. 262° C.-266° C.

출처