Highly regioselective dinitration of toluene over reusable zeolite H-beta

摘要

A nitration system comprising nitric acid, propanoic anhydride and zeolite H-beta 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 re-usable, solvent is not needed and an aqueous work-up is not required.