Cyclohexene Lab Report

This experiment formed cyclohexene from cyclohexanol by the addition of a dehydrating acid. The OH functional group in cyclohexanol is a poor leaving group, which is why the addition of a dehydrating acid is necessary to convert the cyclohexanol into cyclohexene. In this reaction, the OH group is first protonated forming OH2+. Then, a water molecule leaves to form a carbocation. Lastly, a proton is removed from an adjacent carbon to form an alkene. This reaction is conducted in a distillation apparatus. Since cyclohexene boils at a lower temperature than cyclohexanol, the cyclohexene will distill (along with water in an azeotrope mixture) as it’s being formed and collect in the receiving flask. Furthermore, removing the product as it’s formed through simple distillation causes the reaction to shift towards the right, lessening the formation of other unwanted products.

The cyclohexene was then washed again with sodium chloride solution. This will remove any acid that was collected in the receiving flask. The cyclohexene was then dried by adding calcium chloride to remove any remaining water. Lastly, the cyclohexene is once again distilled. The pure cyclohexene collected was weighed to be 0.938 g. An IR spectrum was obtained, and the bromine test was performed on resulting product. The bromine test yielded a positive result; each brown drop of the bromine reagent added disappeared in the solution. The positive result indicates the presence of an alkene. The IR spectrum collected corresponds greatly to the sample spectrum of cyclohexene. The peak at 3023.01indicates a sp2 C-H group, the peaks at 2924.79 and 2859.53 indicates a sp3 C-H, and the peak at 1653.31 indicates a carbon-carbon double bond. Furthermore, the absence of a peak at 3322.01 shows that there is not an alcohol group in the product, meaning that the product did not contain any