Naphthalene was isopropylated (3:2 by moles) (150, 200, 250, or 300degreesC; 2.8 MPa) and the resulting isopropyinaphthalenes (IPN) were disproportionated (6 h, same temp.) over an amorphous aluminosilicate, or a wide-pore zeolite (mordenite, HY, or H-beta), to yield a high-2,6- or a high-2,7-diisopropyinaphthalene (DIPN) alkylate. Shape-selective catalysts and selected reaction conditions allowed to make the process yield high 2,6- (mordenite), or high 2,7-DIPN (zeolite Y or beta) or high 1,4- + 1,3-DIPN (CaREY zeolite) products. Zeolite pore sizes and dimensions of naphthalene, 1- and 2-IPN and all DIPN molecules were given.