反应详情

温度

80 °C

A flame-dried 1 L 3-necked flask, fitted with a 30 cm Vigreux column topped with a distillation head, an argon inlet tube and a magnetic stirring bar, was charged with 36.8g (0.189 mol) of (3E,6R)-6,10-dimethyl-3,9- undecadien-2-one (GC purity 93.6%), 500 mL of isopropanol and 40.0 g (0.196 mol) of aluminum isopropoxide. The reaction mixture was stirred and heated to gentle reflux under argon. Acetone was allowed to distill off at a rate of about 30 drops/min. while maintaining a head temperature of ca. 80° C. After 3.5 hours the reaction was shown by GC to be almost complete with 5% of starting material remaining. The reaction was cooled in an ice bath and the pressure was reduced to ca. 54 mmHg. Isopropanol was distilled off at a head temperature of 30° C.-31° C. until the reaction mixture was concentrated to a volume of about 200 mL. The residual oil was cooled in an ice bath, 200 mL of 2N HCl were carefully added with stirring and the mixture was poured into a separatory funnel containing 200 mL of ether. An additional 200 mL of 2N HCl were added to dissolve some remaining white solid material. The layers were separated and the aqueous phase was extracted with 2×200 mL of ether. The combined organic layers were washed successively with 200 mL of sat. NaHCO3 -solution and 200 mL of brine, dried over MgSO4, filtered and concentrated on the rotovapor. The residue was dried at 0.1 mm for 30 minutes to afford 38.1 g (102.6%) of (2RS,3E,6R)-6,10-dimethyl-3,9-undecadien-2-ol as a light yellow liquid. GC analysis indicated a purity of 94.6%. This material was used as is in Example 2.

1. customA flame-dried 1 L 3-necked flask, fitted with a 30 cm Vigreux column
2. temperatureheated
3. temperatureto gentle reflux under argon
4. distillationto distill off at a rate of about 30 drops/min.
5. temperatureThe reaction was cooled in an ice bath
6. distillationIsopropanol was distilled off at a head temperature of 30° C.-31° C. until the reaction mixture
7. concentrationwas concentrated to a volume of about 200 mL
8. temperatureThe residual oil was cooled in an ice bath
9. addition200 mL of 2N HCl were carefully added
10. stirringwith stirring
11. additionthe mixture was poured into a separatory funnel
12. additioncontaining 200 mL of ether
13. additionAn additional 200 mL of 2N HCl were added
14. dissolutionto dissolve some remaining white solid material
15. customThe layers were separated
16. extractionthe aqueous phase was extracted with 2×200 mL of ether
17. washThe combined organic layers were washed successively with 200 mL of sat. NaHCO3 -solution and 200 mL of brine
18. dry with materialdried over MgSO4
19. filtrationfiltered
20. concentrationconcentrated on the rotovapor
21. customThe residue was dried at 0.1 mm for 30 minutes