反应详情

A 3 L 3-necked flask fitted with a reflux condenser, a mechanical stirrer and an argon inlet tube was charged with 161.5 g (1.033 mol) of (R)-3,7-dimethyloctanal (fractions 1-5 from Example 3, GC purity 97.3%). 413 mL of acetone and 1.24L of 1% ag. KOH. The reaction mixture was stirred vigorously and refluxed for 48 hours. The course of the reaction was monitored by GC. The amount of starting material present was 5% after 25 hours and 3.6% after 48 hours. After cooling in an ice bath, the reaction mixture was poured into a separatory funnel containing 200 mL of brine and extracted with 3×800 mL of hexane/ether 1:1 (parts by volume). The combined organic fractions were washed with 300 mL of brine, dried over MgSO4, filtered and evaporated. Vacuum distillation of the residue through a 30 cm Vigreux column afforded (3E,6R)-6,10-dimethyl-3-undecen-2-one in the following fractions:

1. customA 3 L 3-necked flask fitted with a reflux condenser, a mechanical stirrer and an argon inlet tube
2. temperaturerefluxed for 48 hours
3. customafter 25 hours
4. temperatureAfter cooling in an ice bath
5. additionthe reaction mixture was poured into a separatory funnel
6. extractionextracted with 3×800 mL of hexane/ether 1:1 (parts by volume)
7. washThe combined organic fractions were washed with 300 mL of brine
8. dry with materialdried over MgSO4
9. filtrationfiltered
10. customevaporated
11. distillationVacuum distillation of the residue through a 30 cm Vigreux column