Реакция #56345

Уравнение реакции

3-[1-(tert-butyloxycarbonyl)-L-prolylthio]-2-methylpropanoic acid

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title compound

(4RS-9aS)-Hexahydro-4-methyl-1H,5H-pyrrolo-[2,1-c][1,4]thiazepine-1,5-dione

Растворители

trifluoroacetic acid

anisole

Условия реакции

Обработка

1. 1
   КонцентрированиеAfter fifteen minutes at room temperature the mixture is concentrated to dryness in vacuo
2. 2
   Другоеthe residue triturated with ether-hexane (1:1)
3. 3
   ДругоеThe insoluble material is dried in vacuo
4. 4
   workup.DISSOLUTIONdissolved in dichloromethane (100 ml)
5. 5
   workup.ADDITIONadded dropwise to a stirred solution of 1-cyclohexyl-3-(2-morpholinoethyl) carbodiimide metho-p-toluene sulfonate (20 g) in 900 ml of dichloromethane under argon
6. 6
   Другоеthe dichloromethane is then removed in vacuo
7. 7
   workup.DISSOLUTIONThe residue is dissolved in ethyl acetate
8. 8
   Промывкаthe solution is washed with 10% potassium biculfate, water, saturated sodium bicarbonate and water
9. 9
   ДругоеThe organic layer is dried
10. 10
    Концентрированиеconcentrated

Методика

3-[1-(tert-butyloxycarbonyl)-L-prolylthio]-2-methylpropanoic acid (2.3 g) is dissolved in a mixture of trifluoroacetic acid (15 ml) and anisole (1.1 g). After fifteen minutes at room temperature the mixture is concentrated to dryness in vacuo and the residue triturated with ether-hexane (1:1). The insoluble material is dried in vacuo, dissolved in dichloromethane (100 ml) and added dropwise to a stirred solution of 1-cyclohexyl-3-(2-morpholinoethyl) carbodiimide metho-p-toluene sulfonate (20 g) in 900 ml of dichloromethane under argon. The reaction mixture is stored at room temperature for three days and the dichloromethane is then removed in vacuo. The residue is dissolved in ethyl acetate and the solution is washed with 10% potassium biculfate, water, saturated sodium bicarbonate and water. The organic layer is dried and concentrated to give the title compound.

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