Phenyl isocyanate → N-Phenylcarbamic Acid (3S)-1-azabicyclo[2.2.2]octan-3-yl Ester

Beteiligte Stoffe

Reaktionsschritte

A solution of (3S)-(+)-quinuclidin-3-ol (0.50 g, 3.93 mmol) [M. Langlois, C. Meyer, and J. L. Soulier, Synth. Comm., 23, 1895-1911 (1992)], phenyl isocyanate (0.47 mL, 4.32 mmol, 1.1 equivalents), and dibutyltin dilaurate (0.013 mL, 0.08 mmol) in anhydrous toluene (20 mL) was heated at reflux under nitrogen for 1 hour. The resulting reaction mixture was evaporated under reduced pressure, and the resulting solid was placed in 1N HCl (25 mL). The resulting aqueous mixture was extracted with ethyl acetate (2×25 mL), basified to pH 10 with Na2CO3, and extracted with chloroform (3×50 mL). The chloroform extracts were combined, dried (MgSO4), and evaporated under reduced pressure. The resulting solid was recrystallized using toluene (5 mL) to afford the title compound (0.875 g, 90%) as a white solid: mp 129.0-130.0° C.; FAB LRMS m /z (relative intensity, %) 247 (MH+, 39), 110 (100); [α]22D =-7.5° (c=1.0, MeOH).

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