A NOVEL AND DIRECT SELECTIVE IODINATION OF TOLUENE TO PARA-IODOTOLUENE USING ZEOLITE CATALYSTS

A new and direct procedure for the selective formation of para-iodotol uene from toluene is demonstrated for the first time using iodine mono chloride (ICl) as the iodinating agent and zeolite H-beta as the catal yst. Zeolite H-beta and H.K-L are found to be more para-selective comp ared to other zeolite catalysts and the conventional catalysts, H2SO4 and SiO2. In the presence of a solvent (nitrobenzene) the conversion o f ICl increases and the formation of side products (chlorotoluenes) de creases. The probable mechanism for the formation of iodotoluenes and some amount of chlorotoluenes involves the electrophilic attack of tol uene by I+ and CL(+), respectively.