反应详情

Linoleoyl chloride (25.0 g, 83.6 mmol) was added, dropwise, to a cooled (0° C.) solution of Meldrum's acid (1) (13.3 g, 92.0 mol) and pyridine (14.8 mL, 184 mmol) in CH2Cl2 (180 mL) and the solution was allowed to warm (rt, 16 h). The reaction mixture was washed with an equal volume of HCl (5%, aq., 2×), dried (Na2SO4), filtered and concentrated. The residue was dissolved in dry methanol (200 mL) and heated at reflux (6 h). The solution was cooled (rt), concentrated and the crude oil was purified by flash chromatography (4% EtOAc-hexanes) to yield (11Z,14Z)-methyl 3-oxoicosa-11,14-dienoate (2) (24.5 g, 87%) as a pale yellow oil. Rf 0.38 (10% EtOAc-hexanes). FW 336.51, C21H36O3.

1. washThe reaction mixture was washed with an equal volume of HCl (5%, aq., 2×)
2. dry with materialdried (Na2SO4)
3. filtrationfiltered
4. concentrationconcentrated
5. dissolutionThe residue was dissolved in dry methanol (200 mL)
6. temperatureheated
7. temperatureat reflux (6 h)
8. temperatureThe solution was cooled (rt)
9. concentrationconcentrated
10. customthe crude oil was purified by flash chromatography (4% EtOAc-hexanes)