2.4 g of 4-hydroxy-3-methoxybenzylamine-HCl was suspended in 35 ml of N,N-dimethylformamide (DMF), and stirred. Added were 5 ml of a 5N solution of NaOH, and the mixture was stirred for an additional 10 to 15 minutes. The DMF mixture was chilled in an ice bath, and the stearoyl chloride, prepared above and dissolved in ether, was added dropwise. The mixture was then stirred for 3 hours, allowing it to come to room temperature. The mixture was then poured into 300 ml water, layers separated, and the aqueous layer extracted with ethyl ether. The extracts were washed with HCl, sodium bicarbonate, water, and brine, and then dried and filtered. 5.3 g of crude N-vanillyl-9-octadecynamide was obtained. Purification by recrystallization from toluene and hexane, and then benzene and hexane, gave 2.8 g of analytically pure product. Its structure was confirmed via nuclear magnetic resonance and infrared spectroscopy.
