反应详情

3-Benzyl-8,8-dimethoxy-3-aza-bicyclo[3.2.1]octane (50.4 g, 0.19 mol) and 3N HCl (500 mL) were heated to reflux 4 h (or until judged complete by TLC). Upon cooling to room temperature, the aqueous solution containing product was washed with ether (2×200 mL) then back extracted from the ether layer with 1N HCl (100 mL). The combined aqueous layers were made alkaline with NaOH (˜50 g) in water (500 mL). The product was extracted with EtOAc (3×300 mL), washed with saturated aqueous NaCl solution (1×200 mL), dried over Na2SO4, filtered through a pad of silica (5×4 in), rinsed with 100% EtOAc, and concentrated to a brown liquid (42.0 g, 100%). (TLC 30% EtOAc/hexanes Rf 0.55); 1H NMR (400 MHz, CDCl3) δ 7.37–7.24 (5H), 3.59 (s, 2H), 2.98 (ddd, J=9.5, 4.2, 2.1 Hz, 2H), 2.54 (d, J=10.8 Hz, 2H), 2.16 (brs, 2H), 2.06 (dd, J=12.4, 4.8 Hz, 2H), 1.85 (m, 2H); APCI MS m/z 216.3 (M+1)+.

1. temperatureto reflux 4 h (or until judged complete by TLC)
2. additionthe aqueous solution containing product
3. washwas washed with ether (2×200 mL)
4. extractionthen back extracted from the ether layer with 1N HCl (100 mL)
5. extractionThe product was extracted with EtOAc (3×300 mL)
6. washwashed with saturated aqueous NaCl solution (1×200 mL)
7. dry with materialdried over Na2SO4
8. filtrationfiltered through a pad of silica (5×4 in)
9. washrinsed with 100% EtOAc
10. concentrationconcentrated to a brown liquid (42.0 g, 100%)