반응 #5935

반응 방정식

(R)-2-(4-Chlorophenyl)-4-[(S)-N-(2-naphthalenesulfonyl)prolyl]-3,4-dihydro-2H-1,4-benzothiazine

potassium hydroxide

→

(R)-(+)-2-(4-chlorophenyl)-3,4-dihydro-2H-1,4-benzothiazine

수율 58.7%

용매

ethanol water

반응 조건

후처리

1. 1
   온도the mixture is refluxed for 30 minutes
2. 2
   추출the mixture is extracted with ethyl acetate
3. 3
   세척The ethyl acetate layer is washed with water and saline
4. 4
   건조dried over sodium sulfate
5. 5
   workup.DISTILLATIONdistilled
6. 6
   기타to remove the solvent
7. 7
   기타The residue is purified by silica gel column chromatography (CHCl3)
8. 8
   기타recrystallized from ethyl acetate-hexane twice

실험 절차

(R)-2-(4-Chlorophenyl)-4-[(S)-N-(2-naphthalenesulfonyl)prolyl]-3,4-dihydro-2H-1,4-benzothiazine (9.40 g, 0.017 mole) is suspended in ethanol-water (10:1, 188 ml), and thereto is added 86 % potassium hydroxide (11.2 g, 0.172 mole), and the mixture is refluxed for 30 minutes. The reaction mixture is poured into ice water and the mixture is extracted with ethyl acetate. The ethyl acetate layer is washed with water and saline, dried over sodium sulfate and distilled to remove the solvent. The residue is purified by silica gel column chromatography (CHCl3) and thereafter recrystallized from ethyl acetate-hexane twice to give (R)-(+)-2-(4-chlorophenyl)-3,4-dihydro-2H-1,4-benzothiazine (2.61 g, 58%).

출처