Reaction #1747827

Reaction equation

3-Ethynyl-cyclohex-2-enone

(3-Chloro-propyl)-propyl-amine

Cs2CO3

→

3-(1-Propyl-1,4,5,6-tetrahydro-pyridin-3-yl)-cyclohex-2-enone

Solvents

acetonitril

water

Conditions

Workup

1. 1
   Temperaturethe mixture was refluxed under N2 for 10 h
2. 2
   TemperatureAfter cooling the mixture
3. 3
   Extractionextracted with dichloromethane (3×50 mL)
4. 4
   WashThe combined organic layers were washed with brine
5. 5
   Dryingdried (MgSO4)
6. 6
   Otherevaporated
7. 7
   OtherThe resulting dark oil was purified by column chromatography (silica, ethyl acetate)
8. 8
   Otherto give a yellow red oil

Procedure

3-Ethynyl-cyclohex-2-enone (3.20 g, 26.8 mmol) (from a) above) and (3-Chloro-propyl)-propyl-amine (4.50 g, 33.2 mmol) were mixed in acetonitril (50 mL). Cs2CO3 (100 mg) and KI (200 mg) were added and the mixture was refluxed under N2 for 10 h. After cooling the mixture was diluted with water (50 mL) and extracted with dichloromethane (3×50 mL). The combined organic layers were washed with brine, dried (MgSO4) and evaporated. The resulting dark oil was purified by column chromatography (silica, ethyl acetate) to give a yellow red oil. Yield 5.1 g, 23.3 mmol (87%). IR (neat) 2932, 2871, 1589, 1538, 1157 cm−1; 1H-NMR (CDCl3) δ 6.84 (s, 1H), 5.69 (s, 1H), 3.04-3.12 (m, 4H), 2.44 (t, 2H), 2.33 (t, 2H), 2.18 (t, 2H), 1.83-2.03 (m, 4H), 1.49-1.64 (m, 2H), 0.87 (t, 3H) ppm; 13C-NMR (CDCl3) δ 197.0, 158.5, 140.1, 112.1, 102.4, 56.6, 44.3, 35.6, 23.6, 21.4, 20.2, 20.1, 19.7, 9.6 ppm; MS (CI) m/z 220 (M+1).

Source