Reaktion #632007

Reaktionsgleichung

n-butyllithium

methyl iodide

N-tert-butyl-(3-chloro)propylsulfonamide

n-butyllithium

→

desired product

N-tert-butyl-(1-methyl)cyclopropyl-sulfonamide

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe dry ice bath was removed
2. 2
   Temperaturthe reaction mixture was warmed to room temperature over a period of 1.5 hours
3. 3
   TemperaturThis mixture was cooled to −78° C.
4. 4
   TemperaturThe reaction mixture was warmed to room temperature
5. 5
   Temperaturcooled to −78° C. over a period of 2 hours
6. 6
   TemperaturThe reaction mixture was warmed to room temperature overnight
7. 7
   Sonstigequenched with saturated NH4Cl (100 mL) at room temperature
8. 8
   Extraktionextracted with ethyl acetate (100 mL)
9. 9
   WaschenThe organic phase was washed with brine (100 mL)
10. 10
    Trocknendried (MgSO4)
11. 11
    Filtrationfiltered
12. 12
    Einengenconcentrated in vacuo
13. 13
    Sonstigeto provide a yellow oil which
14. 14
    Sonstigewas crystallized from hexane

Vorschrift

A solution of N-tert-butyl-(3-chloro)propylsulfonamide (4.3 g, 20 mmol) was dissolved in dry THF (100 mL) and cooled to −78° C. To this solution was added n-butyllithium (17.6 mL, 44 mmol, 2.5M in hexane) slowly. The dry ice bath was removed and the reaction mixture was warmed to room temperature over a period of 1.5 hours. This mixture was cooled to −78° C. and a solution of n-butyllithium (20 mmol, 8 mL, 2.5M in hexane) was added. The reaction mixture was warmed to room temperature, cooled to −78° C. over a period of 2 hours, and treated with a neat solution of methyl iodide (5.68 g, 40 mmol). The reaction mixture was warmed to room temperature overnight, then quenched with saturated NH4Cl (100 mL) at room temperature and extracted with ethyl acetate (100 mL). The organic phase was washed with brine (100 mL), dried (MgSO4), filtered, and concentrated in vacuo to provide a yellow oil which was crystallized from hexane to provide the desired product as a slightly yellow solid (3.1 g, 81%): 1H NMR (CDCl3) δ 0.79 (m, 2H), 1.36 (s, 9H), 1.52 (m, 2H), 1.62 (s, 3H), 4.10 (br s, 1H).

Quelle