Synthesis, Structure, and Synthetic Potential of Arenediazonium Trifluoromethanesulfonates as Stable and Safe Diazonium Salts

Abstract

Aromatic diazonium salts are valuable building blocks for organic synthesis; however, in most cases, they are unstable, unsafe, poorly soluble, and/or expensive. In this paper, we have shown that a variety of stable and safe arenediazonium triflates ArN2+ TfO– can be obtained easily and in high yields by diazotization of anilines with tert‐butyl nitrite in the presence of trifluoromethanesulfonic acid. Arenediazonium triflates are relatively shelf‐stable in the dry state. They dissolve well in water, as well as polar and even nonpolar organic solvents. Less than 800 J/g of energy is released during the thermal decomposition of these salts, which indicates their explosion safety. Arenediazonium triflates have a high reactivity in the known reactions of diazonium chemistry, and undergo an unusual metal‐free chlorodediazonization reaction with chloroform and CCl4.