A process is disclosed for the production of polyalkyl tetrahydronaphthalenes wherein a cyclialkylation reaction between an olefinic compound of the general formula ##STR1## wherein R.sup.4, R.sup.5, and R.sup.6 are substituents which do not interfere with a Friedel-Crafts-type reaction and R.sup.5 and R.sup.6 are other than H, and a substituted benzene compound is carried out in the presence of a hydride abstracting reagent, a Lewis acid, and, optionally, a phase transfer agent. In some embodiments, the subject process is specifically carried out in the absence of elemental iodine. The subject process produces the desired compounds in a surprisingly high yield, with a surprisingly high selectivity to the desired product, and at a relatively high rate of reaction, using better, more convenient or less expensive process methodology than many processes known heretofore.