The 1-isopropyl-2-aryl imidazole component of the instant invention may be prepared by a method comprising dehydrogenation of 1-isopropyl-2-aryl imidazoline over a catalyst comprising (1) nickel and (2) from about 2 to 30 wt. % copper and/or chromium, i.e. copper or chromium alone or in combination with the other, at a temperature of about 160??? C. to about 250??? C. and a pressure of about atmos