Additive-free, solvent-free chemical reactions are generally more environmentally benign than alternative processes that involve these reaction components. 2,4-Dinitroanisole (DNAN) is of interest to the military and to industry as a replacement for trinitrotoluene (TNT) in melt-cast explosives. As anisole is a widely used feedstock chemical, the development of an efficient, additive-free, solvent-free method for its dinitration could lead to adoption of a new “green” synthetic route for DNAN manufacture.

The project's goal was the scale‐up (from the previously demonstrated one gram scale to a 500 gram scale) of the additive‐free, solvent‐free dinitration of anisole using the equipment and facilities available at the Los Alamos National Laboratory. 

Through a series of simple optimization processes, the project was successful at scaling demonstrating the development of a solvent-free process for the synthesis of 2,4-dinitroanisole using a batch process. The overall method involves the use of a mixture of propionic anhydride and 98% nitric acid to form the reactive nitrating species, proprionyl nitrate. This nitrating reagent is then added to a highly concentrated solution mixture of anisole and proprionic anhydride slowly over time to produce the desired 2,4-dinitroanisole product. This batch process could be scaled-up to the 270g scale. Flow-reaction methods should allow for larger scale production of DNAN.