تفاعل #5935

معادلة التفاعل

(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

المردود 58.7%

المذيبات

ethanol water

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةthe mixture is refluxed for 30 minutes
2. 2
   استخلاصthe mixture is extracted with ethyl acetate
3. 3
   غسيلThe ethyl acetate layer is washed with water and saline
4. 4
   تجفيفdried over sodium sulfate
5. 5
   workup.DISTILLATIONdistilled
6. 6
   أخرىto remove the solvent
7. 7
   أخرىThe residue is purified by silica gel column chromatography (CHCl3)
8. 8
   أخرىrecrystallized from ethyl acetate-hexane twice

الإجراء التجريبي

(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%).

المصدر