Syntheses, crystal structures, Hirshfeld surface analyses and fluorescence of binuclear complexes with unsymmetrical phenol-based compartmental ligands

Abstract

Two new binuclear complexes, [Ni₂L(OAc)₂(H₂O)]ClO₄·H₂O·CH₂Cl₂ (1) and [Zn₂L(OAc)₂]ClO₄·CHCl₃·0.5C₆H₁₂ (2), have been synthesized by using 2-[N,N-di(2-pyridylmethyl)aminomethyl]-6-(2-imidazolylmethyl)aminomethyl-4-methylphenol (HL) as a ligand. Complexes 1 and 2 have been characterized by FT-IR, powder X-ray diffraction, elemental analysis and single-crystal X-ray diffraction. X-ray crystallographic analyses show that 1 crystallizes in the triclinic P-1 space group, while 2 in the monoclinic C2/c space group. Both Ni1 and Ni2 in 1 are six-coordinate octahedra with a [Ni1O₃N₃] and [Ni2O₄N₂] configuration. In 2, the six-coordinate Zn1 cation displays a distorted octahedral [Zn1O₃N₃] configuration, while the five-coordinate Zn2 cation has a trigonal bipyramidal [Zn2O₂N₃] geometry. The intermolecular interactions in 1 and 2 have been investigated by 3D Hirshfeld surface analyses and 2D fingerprint plots to show that the prominent interactions are H···H and O···H/H···O contacts in 1 and H···H and Cl···H/H···Cl contacts in 2. Notably, the fluorescence emission of 2 has larger intensity than that of the free HL.

Keywords:

• Synthesis
• Nickel(II) complex
• Zinc(II) complex
• crystal structure
• fluorescence
• Hirshfeld surface analysis

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was funded by the National Nature Science Foundation of China (No. 21476115).