Preparation and characterization of ruthenium(II) clathrochelate complexes

Synthetic routes were developed for the preparation of clathrochelate complexes of ruthenium(II) utilizing a totally encapsulating ligand derived from dioxime ligands (1,2-cyclohexanedione dioxime, diphenylglyoxime and dimethylglyoxime) and various boron capping agents (boronic acids, borate esters, and boron halides). These complexes were fully characterized by ¹H NMR, U'V-vis and IR spectroscopies. Cyclic voltammetric electrochemical experiments were performed and indicate that the stability of a ruthenium(III) clathrochelate complex is dependent on the nature of the substituent attached to the boron cap. Specifically, the stability increases with the length of the linear chain alkoxy groups attached to boron, and decreases for bulky alkoxy groups.