A round-trip journey of electrons: Electron catalyzed direct fixation of N2 to azos

The triple bond in N 2 has an extremely high bond energy and is thus difficult to break. N 2 is commonly converted into NH 3 artificially via the Haber-Bosch process, and NH 3 can be utilized to produce other nitrogen-containing chemicals. Here, we developed an electron catalyzed method to directly fix N 2 into azos, by pushing and pulling the electron into and from the aromatic halide with the cyclic voltammetry method. The round-trip journey of electron can successfully weaken the triple bond in N 2 through the electron pushing-induced aryl radical via a “brick trowel” transition state, and then produce the diazonium ions by pulling the electron out from the diazo radical intermediate. Different azos can be synthesized with this developed electron catalyzed approach. This approach provides a novel concept and practical route for the fixation of N 2 at atmospheric pressure into chemical products valuable for industrial and commercial applications. The developed electron catalyzed strategy enables the direct fixation of N 2 to form azo compounds. The triple bond in N 2 can be weakened by the aryl radical generated at the electrode, leading to the formation of “brick trowel” TS. Subsequently, an electron is extracted from the diazo radical intermediate ([Ar-N 2 ] • ) to produce the diazonium ion [Ar-N 2 ] + , facilitating the production of the desired azo compound.