Highly regioselective dinitration of toluene over reusable zeolite H beta

A nitration system comprising nitric acid, propanoic anhydride, and zeolite lip has been developed for dinitration of toluene to give 2,4-dinitrotoluene in 98% yield, with a 2,4-:2,6-dinitrotoluene ratio of over 120. This represents the most selective quantitative method for 2,4-dinitration of toluene; the catalyst is reusable, solvent is not needed, and an aqueous work-up is not required. (c) 2012 Elsevier Inc. All rights reserved.