A dicyanomethyl radical stabilized by ferrocene: a new building block for radical-based dynamic covalent chemistry with redox activity.

A novel dicyanomethyl radical conjugated with ferrocene as an electron donating unit through a benzene linker is prepared for the first time. This radical is in equilibrium with the σ-dimer in solution, and the structure of the σ-dimer was confirmed by X-ray single crystal structure analysis. Due to the monomer/dimer equilibrium, this radical showed unique electrochemical redox behaviour depending on the temperature and scan rate.