Ammonium Chloride → Ethyl (2e,4e,6e,10z,13z,16z,19z)-3-methyl-docosa-2,4,6,10,13,16,19-heptaenoate

Participants

Reaction Conditions

Reaction Steps

A solution of triethyl 3-methyl-4-phosphono-2-butenoate (485 μl, 1.96 mmol) in a 5:1 mixture of anhydrous THF-DMPU (20 ml) was cooled to 0° C., and n-BuLi (2.5 M in hexane, 760 μl, 1.90 mmol) was added. The mixture was stirred for 0° C. for 20 min and then cooled to −78° C. A solution of (2E,6Z,9Z,12Z,15Z)-octadeca-2,4,6,10,13,16,19-pentaenal in THF (2 ml) was added, and the reaction mixture was stirred at −78° C. for an hour. The mixture was then allowed to warm to 0° C. during an hour. Then a saturated aqueous NH4Cl solution was added and the phases were separated. The aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with water and dried (MgSO4). Evaporation of the solvents under reduced pressure followed by flash chromatography on silica:gel (95:5 hexane-EtOAc) gave the ester (120 mg).

Provenance & Evidence