Borane → 3-Quinuclidinone

Temperatur

0 °C

A mixture of trimethylsulfoxonium iodide (16.10 g, 73.2 mmol) and a dispersion of sodium hydride (60% in oil, 3.00 g, 75.0 mmol) in anhydrous dimethyl sulfoxide was stirred at room temperature under nitrogen for 30 minutes. Quinuclidin-3-one (II) (7.05 g, 56.3 mmol) was then added as a solid portionwise, and the resulting mixture was stirred at 65–70° C. under nitrogen for 1 hour. The reaction mixture was cooled, water was added (200 ml), and the resulting solution was extracted with chloroform (3×200 ml). The chloroform extracts were combined, and back-extracted with water (4×200 ml). The chloroform layer was then dried (MgSO4), filtered, and evaporated under reduced pressure to afford spiro[1-azabicyclo[2.2.2]octane-3,2′-oxirane] (6.51 g, 46.8 mmol, 83%) as a clear, colorless liquid. To a stirred solution of spiro[1-azabicyclo[2.2.2]octane-3,2′-oxirane] (5.3 g, 38.1 mmol) in anhydrous tetrahydrofuran (100 ml) at 0° C. was added dropwise a solution of borane in tetrahydrofuran (1.0 M, 38.1 ml, 38.1 mmol), and resulting solution was stirred at 0° C. under nitrogen for 30 minutes. Brine (100 ml) was added cautiously to the reaction solution, and the resulting aqueous mixture was extracted with ethyl acetate (2×100 ml). The organic extracts were combined, dried (MgSO4), filtered, and evaporated under reduced pressure to afford the title compound (II) (4.3 g, 28.1 mmol, 74%) as a white solid: electrospray MS 152 ([M−H]+, 15).

1. customresulting solution
2. extractionthe resulting aqueous mixture was extracted with ethyl acetate (2×100 ml)
3. dry with materialdried (MgSO4)
4. filtrationfiltered
5. customevaporated under reduced pressure

ORD-Eintrag

ord-e533e1e1436146a6876eeb89d8754a1f

Quelldatensatz

uspto-grants-2007_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07196096B2