反应详情

A mixture of 1,4-dioxaspiro[4.5]decan-8-one (10.0 g, 64.0 mmol), morpholine (20 mL) and AcOH (1.0 mL) was stirred for 2.5 h. Sodium cyanoborohydride (8.05 g, 128.0 mmol) was then added in one portion followed by more morpholine (15 mL). An exothermic reaction occurred and the mixture was cooled for 2 min with an ice-bath. Then the mixture was stirred at room temperature for 16 h. Ethanol (120 mL) and water (28 mL) were added to the resulting thick slurry and the white solid filtered, washed with ethanol (2×) and the filtrate concentrated. Ethyl acetate was then added, the precipitate filtered off, washed with ethyl acetate and the filtrate concentrated. The residual oil was purified by Kugelrohr distillation to give 1 (9.03 g, 62%; b.p.140° C./0.05 mmHg) as a clear oil which solidifies on standing.

1. customAn exothermic reaction
2. temperaturethe mixture was cooled for 2 min with an ice-bath
3. stirringThen the mixture was stirred at room temperature for 16 h
4. filtrationthe white solid filtered
5. washwashed with ethanol (2×)
6. concentrationthe filtrate concentrated
7. additionEthyl acetate was then added
8. filtrationthe precipitate filtered off
9. washwashed with ethyl acetate
10. concentrationthe filtrate concentrated
11. distillationThe residual oil was purified by Kugelrohr distillation
12. customto give 1 (9.03 g, 62%; b.p.140° C./0.05 mmHg) as a clear oil which