Hydrochloric Acid → 2-((3-Pyridinyl)methyl)-1-azabicyclo[2.2.2]octan-3-one hydrochloride

Beteiligte Stoffe

Reaktionsschritte

2-((3-Pyridinyl)methylene)-1-azabicyclo[2.2.2]octan-3-one (20 g, 93 mmol) was suspended in methanol (200 mL) and treated with 46 mL of 6 M hydrochloric acid. 10% Palladium on carbon (1.6 g) was added and the mixture was shaken under 25 psi hydrogen for 16 h. The mixture was filtered through diatomaceous earth, and the solvent was removed from the filtrate by rotary evaporation. This provided crude 2-((3-pyridinyl)methyl)-1-azabicyclo[2.2.2]octan-3-one hydrochloride, as a white gum (20 g), which was subsequently treated with 2 M sodium hydroxide (50 mL) and chloroform (50 mL) and stirred for an hour. The chloroform layer was separated, and the aqueous phase was treated with 2 M sodium hydroxide (˜5 mL, enough to raise the pH to 10) and saturated aqueous Sodium chloride (25 mL). This aqueous mixture was extracted with chloroform (3×10 mL), and the combined chloroform extracts were dried (anhydrous magnesium sulfate) and concentrated by rotary evaporation. The residue (18 g) was dissolved in warm ether (320 mL) and cooled to 4° C. The white solid was filtered off, washed with a small portion of cold ether and air dried. Concentration of the filtrate to ˜10% of its former volume and cooling at 4° C. produced a second crop. A combined yield 16 g (79%) was obtained.

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