Hydrochloric Acid → 1-cyclohexyl-2-(2-pyridyl)ethan-1-one

Temperature

-78 °C

A 100 mL round bottom flash was charged with 2-picoline (1.09 mL, 11.02 mmol) and anhydrous THF (15 mL). The solution was cooled to −78° C. and n-butyllithium (7.6 mL of a 1.6M solution in THF, 12.12 mmol) was added dropwise to the cooled solution. After addition was complete, the reaction mixture was warmed to room temperature over one hour and then cooled again to −78° C. N-methoxy-N-methyl cyclohexyl amide (2.0 g, 11.68 mmol) in THF (10 mL) was added dropwise to the reaction mixture. After addition was complete, the reaction was warmed to room temperature over one hour and then stirred for 40 hours. The reaction mixture was then treated with water and 1N HCl (keeping the pH at approximately 12). The reaction mixture was then extracted with methylene chloride (3×20 mL). The organic extracts were combined, dried over anhydrous sodium sulfate, filtered and concentrated under vacuum to provide an orange oil which was purified by flash chromatography (ethyl acetate:hexane, 3:7, silica gel) to provide 1-cyclohexyl-2-(2-pyridyl)ethan-1-one (2.06 g).

1. additionAfter addition
2. temperaturethe reaction mixture was warmed to room temperature over one hour
3. temperaturecooled again to −78° C
4. additionAfter addition
5. temperaturethe reaction was warmed to room temperature over one hour
6. extractionThe reaction mixture was then extracted with methylene chloride (3×20 mL)
7. dry with materialdried over anhydrous sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated under vacuum
10. customto provide an orange oil which
11. customwas purified by flash chromatography (ethyl acetate:hexane, 3:7, silica gel)

ORD record

ord-16912350e9bf4ab18710cfd8a6f84e82

Source dataset

uspto-grants-2003_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06664274B1