Synthesis and Structure of Tetraaqua-bis(2-Formylphenoxyacetato)Zinc(II) Dihydrate

The complex [Zn(Ofpa)2(H2O)4] · 2H2O (Ofpa is 2-formylphenoxyacetate) is synthesized and characterized by X-ray structural analysis and IR spectroscopy. The crystal is monoclinic: a= 25.254(5), b= 6.952(1), c= 13.951(3) A, β = 116.41(3)°, Z= 4, space group C2/c, R= 0.034. The zinc atom in the centrosymmetric complex is coordinated by two monodentate carboxylate ligands (Zn–O 2.123(1) A) and by four water molecules (Zn–O 2.085(1) and 2.092(2) A). The oxygen atom of the aldehyde group is not involved in coordination. Complexes and solvate water molecules in the crystal are united into a three-dimensional framework via hydrogen bonds and π–π interactions.