Mononuclear cadmium(II) halide complexes of triphenylphosphoniobutyrate, [CdCl 2L 2-H 2O] and [CdX 2L 2] (X = Br, I)(L = Ph 3P + (CH 2) 3CO 2−)

Abstract

Three mononuclear cadmium(II) complexes containing the tertiary phosphine betaine ligand triphenylphosphoniobutyrate, Ph 3P +(CH 2) 3CO 2 −, (L) have been synthesized and characterized by single crystal X-ray analysis. In CdCl 2L 2 · H 2O ( 1) the cadmium(II) atom is coordinated by pairs of unidentate betaine ligands and chloro ligands in a tetrahedral environment, and the primarily discrete species are joined by donor hydrogen bonds from the solvated water molecules to the pendant oxygen atom of the betaine ligands to form a dimer. In CdBr 2L 2 ( 2) the cadmium(II) atom is coordinated in a similar manner, but one CdBr distance is so long that it may be considered as a weak interaction. In CdI 2L 2 ( 3) the betaine ligands act differently in the bidentate chelate and unidentate modes.