Synthesis and Crystal and Molecular Structures of Nickel(II) and Copper(II) 1,5-Napthalenedisulfonate Complexes with Nicotinamide

Resumo

Coordination compounds of nickel(II) and copper(II) 1,5-naphthalenedisulfonates with nicotinamides, [Ni(L)₂(H₂O)₄](Nds) · 3H₂O (I) and [Cu(L)₂(H₂O)₄](Nds) (II) (L = nicotinamide, NC₅H₄C(O)NH₂, Nds² = doubly deprotonated 1,5-naphthaledisulfonate anion, \({{{\text{C}}}_{{{\text{1}}0}}}{{{\text{H}}}_{{\text{6}}}}({\text{S}}{{{\text{O}}}_{{\text{3}}}})_{{\text{2}}}^{{{\text{2}}-}}\)), were synthesized and studied by IR and diffuse reflectance spectroscopy. The crystal structures of I and II were determined by X-ray diffraction (CIF files CCDC nos. 1863367 (I) and 1863368 (II)). In both structures, the Ni and Cu atoms are coordinated by two nitrogen atoms of two monodentate L ligands and by four oxygen atoms of water molecules. The coordination polyhedron of Ni in I is a slightly distorted octahedron and that of Cu in II is a tetragonal (4 + 2) bipyramid extended due to the Jahn–Teller effect, with the O(H₂O) atoms in the axial positions. The [M(L)₂(H₂O)₄]²⁺ complex cations, the Nds^2– anions, and water molecules of crystallization in II are combined by a branched network of hydrogen bonds.