Rh → Sb Interactions Supported by Tris(8-quinolyl)antimony Ligands

The ligands tris(8-quinolyl)stibine and tris(6-methyl-8-quinolyl)stibine have been synthesized and complexed to rhodium using (MeCN)3RhCl3. The resulting complexes feature an unusual [RhSb]VI core as a result of the formal insertion of the antimony center into one of the Rh–Cl bonds. Computational analysis using density functional theory (DFT) methods reveals that the resulting Rh–Sb σ bond is polarized toward the Rh atom, suggesting a description of this linkage as a Rh → Sb Z-type interaction.