반응 #5940

반응 방정식

2-chloro-3-oxo-3,4-dihydro-2H-1,4-benzothiazine

thiophene

→

3-oxo-2-(2-thienyl)-3,4-dihydro-2H-1,4-benzothiazine

수율 70.3%

용매

methylene chloride

반응 조건

후처리

1. 1
   기타the organic layer is separated
2. 2
   추출The aqueous layer is extracted with ethyl acetate
3. 3
   workup.DISTILLATIONdistilled
4. 4
   기타to remove the solvent
5. 5
   기타The resulting solid material is recrystallized from ethanol

실험 절차

To a solution of 2-chloro-3-oxo-3,4-dihydro-2H-1,4-benzothiazine (9.38 g) and thiophene (7.91 g) in methylene chloride (250 ml) is added in portions stannic chloride (12. 2 g) at 0° to 5° C. After stirring at the same temperature for 45 minutes, the mixture is poured into ice water, and the organic layer is separated. The aqueous layer is extracted with ethyl acetate, and the ethyl acetate layer is combined with the above organic layer and distilled to remove the solvent. The resulting solid material is recrystallized from ethanol to give 3-oxo-2-(2-thienyl)-3,4-dihydro-2H-1,4-benzothiazine (8.17 g) as crystals.

출처