Hydrochloric Acid → Octadecanoic acid, 3-oxo-, ethyl ester

Participants

Reaction Conditions

Reaction Steps

502 ml of a 15.12% by weight solution of butyllithium in hexane was added dropwise at -78° C. over a period of 30 minutes to a solution of 128 ml of cyclohexylisopropylamine in 800 ml of tetrahydrofuran. After the addition was complete, the reaction mixture was allowed to warm up to 0° C. over a period of 30 minutes. It was then again cooled to -78° C., after which 38 ml of ethyl acetate were added over a period of 5 minutes. The mixture was then stirred at the same temperature for 10 minutes, after which 75.0 g of palmitoyl chloride were added dropwise to it over a period of 5 minutes. The mixture was then stirred at -78° C. for 10 minutes, after which 250 ml of 20% v/v aqueous hydrochloric acid was added dropwise to the reaction mixture. The reaction mixture was then allowed to warm to room temperature, and 1 liter of diethyl ether was added. The resulting two layers were separated, and the aqueous layer was extracted with diethyl ether. The organic layer was combined with the extract, and this was washed, in turn, with a saturated aqueous solution of sodium bicarbonate and with an aqueous solution of sodium chloride. It was then dried and concentrated by evaporation under reduced pressure. The residue was allowed to stand to produce crystals, which were collected by filtration, to give 55.61 g of the title compound. Recrystallization of the product from cold ethanol gave white prisms melting at 38°-39° C.

Provenance & Evidence