反应详情

--2,2,2-Trichloroethyl-2-[(z,z,z) octadeca-6,9,12-trienoyl]benzoate (15 1 g) was dissolved in a mixture of tetrahydrofuran (750 ml), acetic acid (675 ml) and water (75 ml). Zinc dust (150 g) was added. The mixture was stirred at room temperature under nitrogen for 1.5 hours and then allowed to stand for twenty hours. Excess zinc and zinc salts were filtered off through Celite washing the filter pad with tetrahydrofuran (100 ml) and the flitrate was evaporated at 25° C./10 mmHg to remove the tetrahydrofuran. The acetic acid and water was then removed at 25° C./0.5 mmHg. Higher temperatures tend to decompose the product. The resulting oil was dissolved in diethyl ether (1000 ml) and the resulting solution was washed with water (4×200 ml). After drying (Na2SO4), the ether was evaporated (25° C./10 mmHg) to give a pale yellow oil which was subjected to a dry column (Packing: Matrex silica (1 Kg), pore size 60A, particle size 35-70μm, Fraction size: 1000 ml). The requisite tractions were collected, the solvent evaporated as before, the last traces being removed at 25° C./0.1 mmHg to give 2-[(z,z,z) octadeca-6,9,12,-trienoyl]benzoic acid, (77.8 g, 68%) as a pale orange oil which solidified to a wax in the refrigerator.

1. waitto stand for twenty hours
2. filtrationExcess zinc and zinc salts were filtered off through Celite
3. washwashing the filter pad with tetrahydrofuran (100 ml)
4. customthe flitrate was evaporated at 25° C./10 mmHg
5. customto remove the tetrahydrofuran
6. customThe acetic acid and water was then removed at 25° C./0.5 mmHg
7. dissolutionThe resulting oil was dissolved in diethyl ether (1000 ml)
8. washthe resulting solution was washed with water (4×200 ml)
9. dry with materialAfter drying (Na2SO4)
10. customthe ether was evaporated (25° C./10 mmHg)
11. customto give a pale yellow oil which
12. customThe requisite tractions were collected
13. customthe solvent evaporated as before, the last traces
14. custombeing removed at 25° C./0.1 mmHg