Weigh 11.4 g of 10,18-heptadecanedione, 25 mL of hydrazine monohydrate, 25 mL of glacial acetic acid, and 305 mL of 1-octanol, and reflux at 140-150 °C for 9 hours with stirring. Remove the water and excess hydrazine formed using a Dean-Stark apparatus. Add a sodium octanoate solution (11 g sodium dissolved in 120 mL of 1-octanol) to the hydrazone. Then reflux the mixture for 24 hours. Raise the oil bath temperature to 180 °C. Neutralize the cold mixture with 4 M HCl. Evaporate the organic phase to dryness under vacuum (~133 Pa). The remaining semi-solid was crystallized from ethanol to give an impure white solid, which was finally purified by silica gel column chromatography (eluent toluene) to give N-HEPTACOSANE in 29% yield, with a melting point of 59 °C.
