Dehydration of Cyclohexanol

H₂SO₄

C₆H₁₁OH --------> C₆H₁₀ + H₂O

Heat

Boiling Point 160^oC Boiling Point 83^oC

Procedure

Add 9 mL of Cyclohexanol to a 50-mL round-bottomed flask.

Add 5 mL of phosphoric acid and 1 mL of sulfuric acid to the flask, and swirl the flask to

thoroughly mix its contents.

Add your magnetic stirring bar and assemble the flask for fractional distillation. Use a 50-mL

Erlenmeyer flask as your receiver.

Heat the reaction mixture at a setting of 7, and collect all distillates, keeping the head

temperature BELOW 90^oC. (If not heated too strongly the reaction temperature remains below 80^oC

for most of the reaction period).

When no more distillate is observed coming from the condenser, discontinue heating.

Transfer the distillate to a test tube, add 1-2 mL of saturated sodium chloride solution, and

shake the corked test tube well and allow the layers to separate.

Remove the AQUEOUS portion using a disposable pipet .

Transfer the ORGANIC layer to a dry 50-mL Erlenmeyer flask and add a spatula tip full of

anhydrous sodium sulfate. Occasionally swirl the flask for the next two minutes.

After cooling, pour the contents of the still pot down the sink in your hood, followed by lots of water. Rinse and clean the flask in your hood sink as well (this minimizes the amount of alkene getting into the lab itself).

Test the distillate for unsaturation using the Baeyer Test

Pour the remainder of your alkene into the recovery bottle at the front of the room,

leaving the drying agent in the erlenmeyer flask.