Synthesis of Benzyl cyanide

Dissolve 30 g of sodium cyanide in 140 mL of water in a round bottom flask, also set up a pressure equalized addition funnel with 44 mL of benzyl chloride, 40 mL ethanol mixture. Heat the flask to 50°C and slowly start adding the benzyl chloride mixture with stirring. The addition should be completed in 30 min, then attach reflux condenser. Reflux for 4h in a water bath. After refluxing cool down the solution, then set up for a simple distillation to distill the ethanol off. When you have collected about 35 mL of distillate, turn off the heat and allow to cool to room temperature. Pour the solution into a separatory funnel, allow the layers to separate and discard the bottom layer. Mix 20 mL of conc. sulfuric acid with 40 mL of water, pour half of the still hot acid solution to the separatory funnel and shake the solutions, discard bottom layer and repeat. Prepare 40 mL of a concentrated solution of sodium bicarbonate, discard the bottom layer. Then wash it with 40 mL saturated sodium chloride solution. Collect the upper brown layer, and distill in a vacuum.




Slowly adding the benzyl chloride mixture


Refluxing, oil is separating so stir well


Mixture after 4h, cooling down to room temperature


Distill the ethanol out


Discard the bottom layer, after pouring it into the separatory funnel


Wash with sulfuric acid


Wash with sodium carbonate and sodium chloride

The crude product

Scroll to top