Cadmium Carboxylate Chemistry: Preparation, Crystal Structure, and Thermal and Spectroscopic Characterization of the One-dimensional Polymer [Cd(O₂CMe)(O₂CPh)(H₂O)2]n

Compound [Cd(O 2 CMe)(O 2 CPh)(H 2 O) 2 ]n (1) was initially obtained in a serendipitous way during efforts to prepare a Cd II /PhCO 2 −/bepy complex (bepy = 2-benzoylpyridine). With the identity of 1 established by single-crystal X-ray crystallography, a rational preparative route to this complex was designed and carried out by reacting Cd(O 2 CMe) 2 ·2H 2 O with a slight excess of PhCOOH in MeCN under reflux. The crystal structure of 1 consists of isolated zig-zag chains. The Cd II atom is coordinated to five carboxylate and two aqua oxygen atoms creating a distorted, capped trigonal prismatic coordination polyhedron. The acetate group exhibits the η 1 :η 2 :μ 2 coordination mode, while the benzoate ligand is chelating. There is an extensive hydrogen-bonding network which reinforces the chains and also links them generating sheets. The new complex was characterized by IR, far-IR, Raman, CP MAS and solution 113 Cd NMR spectroscopy. The spectroscopic data are discussed in terms of the nature of bonding and the known structure. An anhydrous compound with the empirical formula Cd(O 2 CMe)(O 2 CPh) was isolated during the thermal decomposition of 1; the vibrational study of this thermally stable intermediate supports an 1D polymeric structure with 6-coordinate Cd II ions.