The present invention provides a process for the conversion of a reactant into a reaction product in the presence of a novel acid catalyst complex comprising an organosulfonic acid having the formula[(R.sup.2 O).sub.2 P(O)].sub.y R(SO.sub.r R.sup.1).sub.xwherein R is an organo radical having at least one covalent carbon-fluorine bond, R.sup.1 is hydrogen, R.sup.1 is a hydrocarbyl radical having up to 20 carbon atoms or hydrogen, r is 2 or 3, x is an integer from 1 to 3, y is an integer of from 1 to 3 with the proviso that the phosphorus and the sulfur are covalently bonded to a carbon atom and which organosulfonic acid has been contacted with a Lewis Acid to produce a catalyst complex containing said Lewis Acid. In the elected claims, a process for providing a high octane alkylate stream by converting a mixture comprising isoparaffins and olefins into said alkylate in the presence of said acid catalyst complex, is described.