The existence of a persisting allylic compound at equilibrium of the dehydration of 4-methyl cyclohexanol in 80% w/w sulfuric acid is supported by absorbance vs. time plots from UV-vis analysis . The peak seen at 305 nm is an indication of the formation of an allylic carbocation over time and therefore can support a proposed mechanism for this reaction. Kinetic analysis of the compound at 35.0°C, 48.5°C, 60.0°C, and 66.8°C shows that the dehydration reaction is first order with rate constants of 1.83 x 10-5s-1 , 1.27 x 10-4s-1 , 9.28x10-4s-1, and 9.55x10-4s-1 respectively for each temperature and an activation energy of 116 kJ mol-1 .
Nicholas, Dequina, "Activation Energy of the Formation of the Allylic Carbocation in the Acid Catalyzed Dehydration of 4-Methylcyclohexanol" (2009). Senior Research Projects. 171.