Molecular, Supramolecular Structures Combined with Hirshfeld and DFT Studies of Centrosymmetric M(II)-azido {M=Ni(II), Fe(II) or Zn(II)} Complexes of 4-Benzoylpyridine

The supramolecular structures of the three metal (II) azido complexes [Fe(4bzpy)(4)(N-3)(2)]; 1, [Ni(4bzpy)(4)(N-3)(2)]; 2 and [Zn(4bzpy)(2)(N-3)(2)](n); 3 with 4-benzoylpyridine (4bzpy) were presented. All complexes contain hexa-coordinated divalent metal ions with a slightly distorted octahedral MN6 coordination sphere. Complexes 1 and 2 are monomeric with terminal azido groups while 3 is one-dimensional coordination polymer containing azido groups with mu(1,1) and mu(1,3) bridging modes of bonding. Hirshfeld analysis was used to quantitatively determine the different contacts affecting the molecular packing in the studied complexes. The most common interactions are the polar O horizontal ellipsis H and N horizontal ellipsis H interactions and the hydrophobic C horizontal ellipsis H contacts. The charges at the M(II) sites are calculated to be 1.004, 0.847, and 1.147 e for complexes 1-3, respectively. The degree of asymmetry is the highest in the case of the terminal azide in complexes 1 and 2 while was found the lowest in the mu(1,1) and mu(1,3) azide bonding modes in the Zn(II) complex 3. These facts were further explained in terms of atoms in molecules (AIM) topological parameters.

Automated summary

The supramolecular structures of three metal (II) azido complexes with 4-benzoylpyridine were presented. Complexes 1 and 2 are monomeric with terminal azido groups, while complex 3 is a one-dimensional coordination polymer. The molecular packing in the complexes is affected by polar O-H and N-H interactions, as well as hydrophobic C-H contacts.