Реакция #5937

Уравнение реакции

(R)-3-(4-chlorophenyl)-1-[(S)-N-(2-naphthalenesulfonyl)prolyl]-2,3-dihydro-1H-naphtho[2,1-b][1,4]thiazine

potassium hydroxide

→

(R)-(+)-3-(4-chlorophenyl)- 2,3-dihydro-1H-naphtho[2,1-b][1,4]thiazine

Выход 63.1%

Растворители

ethanol water

Условия реакции

Обработка

1. 1
   Температураis refluxed under argon for one hour
2. 2
   Экстракцияthe mixture is extracted with ethyl acetate
3. 3
   ПромывкаThe ethyl acetate layer is washed with water and saline
4. 4
   Сушкаdried over sodium sulfate
5. 5
   workup.DISTILLATIONdistilled
6. 6
   Другоеto remove the solvent
7. 7
   ДругоеThe residue is purified by silica gel column chromatography (CHCl3)
8. 8
   Другоеrecrystallized from ethyl acetate-hexane

Методика

A mixture of (R)-3-(4-chlorophenyl)-1-[(S)-N-(2-naphthalenesulfonyl)prolyl]-2,3-dihydro-1H-naphtho[2,1-b][1,4]thiazine (11.50 g, 0.019 mole), 86 % potassium hydroxide (15.0 g, 0.227 mole) and ethanol-water (10:1, 230 ml) is refluxed under argon for one hour. 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 to give (R)-(+)-3-(4-chlorophenyl)- 2,3-dihydro-1H-naphtho[2,1-b][1,4]thiazine (3.74 g, 63%). M.p. 205°-206° C.

Источник