Synthesis, X-ray structure, and DFT studies of five- and eight-coordinated Cd(II) complexes with s-triazine N-pincer chelate

Abstract

The synthesis and spectral characterizations of [CdLCl₂] (1) and [CdL(NO₃)₂(H₂O)] (2) pincer complexes of the s-triazine core ligand (L), 2,4-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine), are presented. Complexes 1 and 2 have five- and eight-coordinated Cd(II) ions, respectively, where L acts as a neutral tridentate N-chelate. The coordination sphere is completed by two coordinated Cl^– anions in 1 and with one water molecule and two bidentate nitrate anions in 2. The neutral complex units of 1 and 2 are packed by the polar Cl…H and O…H hydrogen bonds, respectively. Using Hirshfeld analysis, the percentages of these contacts are 24.5% and ∼36.8%, respectively. Both complexes showed some anion-π stacking interactions. Thermogravimetric analysis showed that 1 is thermally more stable than 2. The orbital-orbital interactions included in the Cd-Cl, Cd-O, and Cd-N coordinate bonds were analyzed using DFT calculations. The calculated NMR results correlated very well with the experimental data.

Graphical Abstract

Keywords:

• Cd(II)
• pincer
• s-triazine
• Hirshfeld
• NBO

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors extend their sincere appreciation to the Deanship of Scientific Research at King Saud University for providing funding to this Research group #RGP-234.