SYNTHESIS OF HEXACOSANE

STEP 1: Dissolve 5.0 g of pure myristic acid (tetradecanoic acid) in 25 ml of absolute methanol to which 0.1 g of sodium has been added. 

STEP 2: Place the solution in a cylindrical cell (25 cm long, 3 cm diameter) provided with two platinum plate electrodes (2.5 x 2.5 cm) set 1-2 mm apart. 

STEP 3: Electro­lyse at about 1 amp until the electrolyte is just alkaline (pH 7.5-8). 

STEP 4: Cool the cell in an ice bath during the electrolysis. 

STEP 5: Reverse the current from time to time; this will help to dislodge the coating of insoluble by-products on the electrodes. 

STEP 6: Neutralise the cell contents by adding a few drops of glacial acetic acid, and evaporate most of the solvent under reduced pressure using a rotary evaporator. 

STEP 7: Pour the residue into the water and extract the crude product with ether. 

STEP 8: Wash the ethereal solution with dilute sodium hydroxide solution, dry (magnesium sulphate) and evaporate the solvent. 

STEP 9: Recrystallise the resi­due from light petroleum (b.p. 40-60 °C). 

STEP 10:The yield of hexacosane, m.p. 57­58 °C is 2.4 g (65%).