Nickel Salicylideniminato 1D MOFs via Electrochemical Polymerization

Polymers derived from nickel complexes of salicylaldimines are extensively studied due to their electrochemical, catalytic, and sensing properties. However, almost all studies are devoted to the polymers obtained from tetradentate bis(salicylidenaldiminato) complexes, in which the aromatic rings are bound via an imine bridge. Herein, we report a first systematic study focused on the polymerization of salicylaldimine nickel complexes without a bridge between the imine fragments. As a result, an impact of the ligand structure on the polymerization ability of the complexes and electrochemical behavior of the polymers obtained thereof was discovered and quantified. An observed phenomenon was rationalized both computationally and experimentally, involving the electrochemical and spectroelectrochemical techniques. No bridge needed: The computational, electrochemical, and spectral studies of bridgeless ML2 type salicylaldimine nickel complexes revealed influence of the structural features of the molecule on the ability to form conductive coordination polymers by electropolymerization. The proposed computational descriptor may extend the predictive scope of the in silico screening of this class of complexes and coordination polymers.