Synthesis and Analysis of a Family of Cerium(IV) Halide and Pseudohalide Compounds

The first complete series of isostructural cerium­(IV) halide complexes in a conserved ligand framework was isolated by halogen-exchange reactions of CeF­[N­(SiMe3)2]3 with Me3SiX (X = Cl–, Br–, I–). The use of Me3SiX reagents represents a useful method for obtaining cerium­(IV) complexes. Spectroscopic, electrochemical, and computational analyses were used to describe the effects of halide coordination on the cerium­(IV) metal center. Cerium­(IV) complexes of the pseudohalide ligands: N3– and NCS– were also synthesized and evaluated in comparison to the halide congeners. The results showed that the complexes exhibited reduction potentials and electronic absorption energies that varied with the identity of the halide or pseudohalide ligand.