Реакция #69579

Уравнение реакции

1,1-dimethylethyl (2R)-2-methyl-1-piperazinecarboxylate

DIPEA

HCl

1,4-dioxane

4-(trifluoromethyl)benzenesulfonyl chloride

→

title compound

Выход 82.8%

(3R)-3-Methyl-1-{[4-(trifluoromethyl)phenyl]sulfonyl}piperazine

Выход 82.8%

Растворители

DCM

Условия реакции

Обработка

1. 1
   Промывкаthen washed with water (250 ml)
2. 2
   Другоеdried on a phase separation cartridge
3. 3
   Концентрированиеconcentrated in vacuo
4. 4
   workup.DISSOLUTIONThe obtained product was dissolved in 1,4-dioxane (60 ml)
5. 5
   КонцентрированиеThe mixture was concentrated under vacuo
6. 6
   workup.DISSOLUTIONthen dissolved in EtOAc (150 ml)
7. 7
   Промывкаwashed with 2N aq. NaOH solution (200 ml)
8. 8
   Другоеthen dried on a phase separation cartridge
9. 9
   Концентрированиеconcentrated in vacuo
10. 10
    workup.DISSOLUTIONThe product was then dissolved in EtOAc (100 ml)
11. 11
    Экстракцияextracted with 2M aq. HCl (2×200 ml)
12. 12
    workup.ADDITION2M aq. NaOH solution was added to the aqueous layer until basic pH
13. 13
    Экстракцияthe product was extracted with EtOAc (500 ml)
14. 14
    ДругоеThe organic layer was dried on a phase separation cartridge
15. 15
    Концентрированиеconcentrated under vacuo

Методика

To a solution of 1,1-dimethylethyl (2R)-2-methyl-1-piperazinecarboxylate (2.95 g, 14.73 mmol) in DCM (120 ml) was added DIPEA (5.40 ml, 30.9 mmol) and then 4-(trifluoromethyl)benzenesulfonyl chloride (3.96 g, 16.20 mmol). The reaction mixture was stirred 2.5 hours at room temperature then washed with water (250 ml), dried on a phase separation cartridge and concentrated in vacuo. The obtained product was dissolved in 1,4-dioxane (60 ml) and treated with 4M aq. HCl in 1,4-dioxane (18.41 ml, 73.6 mmol) overnight. The mixture was concentrated under vacuo then dissolved in EtOAc (150 ml), washed with 2N aq. NaOH solution (200 ml) then dried on a phase separation cartridge and concentrated in vacuo. The product was then dissolved in EtOAc (100 ml) and extracted with 2M aq. HCl (2×200 ml). 2M aq. NaOH solution was added to the aqueous layer until basic pH then the product was extracted with EtOAc (500 ml). The organic layer was dried on a phase separation cartridge and concentrated under vacuo to give the title compound (3.76 g).

Источник