塩化アルミニウムによるイソプロピルシクロペンタンの異性化反応

抄録

Liquid-phase isomerization of isopropylcyclopentane has been studied at temperatures ranging from -5 to 50°C, using anhydrous aluminum chloride as catalyst. It was observed that the initial main products from isopropylcyclopentane were 1-cis-2- and 1-trans-2-dimethylcyclohexane, most of them being then converted to 1, 3-dimethylcyclohexanes and 1, 4-dimethylcyclohexanes in a consecutive manner.
The reaction was found to obey the first order kinetics under the given reaction conditions. The values of activation energy and apparent A-factor were 11.2kcal/mol and 4.7×10⁴sec^-1, respectively.
Experimental observation can be explained in terms of the formation of cyclopentylisopropyl carbonium ion followed by ring-expansion.