Reaktion #669614

Reaktionsgleichung

Cyclohexylacetylene

6,7-dimethoxyquinolin-3-yl trifluoromethane sulfonate

NH4OH

n-BuLi

→

3-cyclohexylethynyl-6,7-dimethoxyquinoline

Lösungsmittel

THF

CHCl3

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto warm to room temperature
2. 2
   workup.STIRRINGstirred for 3/4 hour
3. 3
   SonstigeThe reaction mixture is transferred via cannula to a flask
4. 4
   TemperaturThis is then heated to 50° C. under N2 for 41/2 hours
5. 5
   workup.STIRRINGstirred for 20 min
6. 6
   SonstigeThe aqueous layer is separated
7. 7
   Waschenthe organic layer washed with brine
8. 8
   Trocknendried over MgSO4
9. 9
   Filtrationfiltered
10. 10
    Sonstigeevaporated
11. 11
    Sonstigechromatographed with 4:1 hexane

Vorschrift

This reaction is carried out under anhydrous conditions. Cyclohexylacetylene (700 mg; 6.47 mmol) in 10 mL. THF is cooled to 0° C. To this is added 2.5M n-BuLi (3.0 mL; 7.44 mmol) and stirred for 30 min. at 0° C. under N2 atm and then 1.0M ZnCl2 (7.4 mL; 7.44 mmol). This is allowed to warm to room temperature and stirred for 3/4 hour. The reaction mixture is transferred via cannula to a flask containing 6,7-dimethoxyquinolin-3-yl trifluoromethane sulfonate (500 mg; 1.48 mmol) and Pd(PPh3)4 (83 mg; 0.074 mmol) in 4 mL of THF. This is then heated to 50° C. under N2 for 41/2 hours. The reaction mixture is then poured into 90 mL of 10% NH4OH, diluted with CHCl3 and stirred for 20 min. The aqueous layer is separated, and the organic layer washed with brine, dried over MgSO4, filtered, evaporated and chromatographed with 4:1 hexane: EtOAc to obtain 3-cyclohexylethynyl-6,7-dimethoxyquinoline, which is recrystallized from hexane, identified by NMR and used directly in the next step.

Quelle