A new compound constructed from Keggin anions and Cu-5,6-diamino-1,10-phenanthroline complexes: synthesis, structure, and characterization

Abstract

A new inorganic–organic hybrid based on polyoxometalate, [Cu₂(daphen)₂(H₂O)₄(PW₁₁W^VO₄₀)] · 6H₂O (1) (daphen = 5,6-diamino-1,10-phenanthroline), was synthesized hydrothermally and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, and thermal analysis. Single-crystal X-ray diffraction analysis reveals that in 1 the Keggin anion [PW₁₂O₄₀]⁴⁻ is tetradentate, linking four Cu(II)-daphen fragments with its four terminal oxygen atoms in a plane; Cu²⁺ is coordinated by two terminal oxygen atoms of two [PW₁₂O₄₀]⁴⁻ anions, two water molecules, and two nitrogen atoms of the phen ring of a daphen, forming a polymeric layer. The 3-D architecture of the compound is further formed via hydrogen bonds between these layers. The daphen is bidentate chelating and does not participate in formation of hydrogen bonds. Redox of 1 was examined.

Keywords:

• Polyoxometalate
• Phenanthroline derivative
• Supramolecular compound
• 2-D structure
• Hydrogen-bonding