Organic Chem Lab

O CHEM LaB

Weigh round bottom flask. Place 7.5 ml of 4-methylcyclohexanol in-tarred 50 ml round bottom flask. Reweigh round bottom flask to get accurate mass of 4-ethylcyclohexanol. Add 2 ml of 85% phosphoric acid and 30 drops of concentrated sulfuric acid. Mix the liquids together using stirring rod and then add boiling chip. Assemble distillation apparatus, shown in figure 1. Use 25 ml flask as receiving vessel and keep immersed in ice bath to minimize evaporation of 4-ethylcyclohexene. Turn on water and make sure it is flowing steadily, avoid high pressure. Turn on heating mantle, increase temperature until mixture boils and product distills, collecting in receiving flask. Distillation takes about 30 minutes. Distilling too rapidly will cause mixture to distill over before it reacts. Closely monitor temperature at head and ensure it does not get close to boiling point of starting material. Continue until no more liquid is left. Add 1-2 ml of saturated sodium chloride solution directly into test tube that was used as receiving flask. Gently wash distillate with saturated sodium chloride solution by using pipette to mix the two layers. Allow layers to separate and remove aqueous. Transfer organic layer to Erlenmeyer flask. Add small amount of anhydrous sodium sulfate and swirl flask. If clumps form, add little more of it until there are small amounts of loose solid in flask. Stopper flask and set aside for 10-15 minutes to ensure that all traces of water, condenser and receiving flask used for reaction. Rinse all with acetone and then dry them.