Toward steric control of guest binding modality: a cationic Co(ii) complex exhibiting cation binding and zero-field relaxation.

We present the syntheses and characterization of several salts of a trigonal prismatic cobalt(ii) complex with a 1,3,5-triaminocyclohexane (tach)-derived ditopic ligand. The air- and moisture-stable tetraphenylborate salt (2) shows slow magnetic relaxation under both zero and applied dc fields. This complex also exhibits an unexpected ability to interact with a cationic sodium guest ion, highlighting the ambifunctional binding nature of amide groups within an iminopyridine scaffold.