Multimodal Reactivity of N–H Bonds in Triazanes and Isolation of a Triazinyl Radical

摘要

The employment of nitrogen Lewis acids based on nitrenium cations has been increasingly featured in the fields of main group chemistry and catalysis. A formally reduced form of nitrenium Dcyclic triazanes Eare intriguing chemical compounds, the chemistry of which is completely unexplored. In this work, we reveal that N–H-triazanes exhibit unusual N–H bond properties; namely, they can serve as protons, hydrides, or hydrogen atom donors. This unique multimodal reactivity provides an N-cation, N-anion, or N-radical from the same species. It allowed us to isolate, for the first time, a stable naphto­[1,2,3]­triazinyl radical, which was fully characterized both computationally and experimentally, including its monomeric X-ray structure. Moreover, this radical can be prepared directly from the nitrenium cation by a single electron reduction (E = −0.46 V), and this process is reversible. We envision versatile uses of this radical in synthetic and materials chemistry.