Synthesis and characterization of copper(II)-bis(pyridin-2-carbonyl)amine (pyca)-pseudohalide complexes: 2D superstructure formation through CH⋯O hydrogen bond and π⋯π interaction in [Cu(pyca)Cl(NCO)]
✍ Scribed by Habibar Chowdhury; Sk Hafijur Rahaman; Rajarshi Ghosh; Sajal Kumar Sarkar; Hoong-Kun Fun; Barindra Kumar Ghosh
- Publisher
- Elsevier Science
- Year
- 2007
- Tongue
- English
- Weight
- 596 KB
- Volume
- 826
- Category
- Article
- ISSN
- 0022-2860
No coin nor oath required. For personal study only.
✦ Synopsis
Three copper(II) complexes of type [Cu(pyca)(Cl)(Y)] (1-3) [pyca = bis(pyridin-2-carbonyl)amine; Y = NCO À , N 3 À , NCS À ] have been synthesized and characterized on the basis of microanalytical, spectroscopic, magnetic, electrochemical, and other physicochemical properties. X-ray diffraction study in [Cu(pyca)(Cl)(NCO)] (1) reveals copper(II) center in a distorted trigonal bipyramidal environment through coordination by two pyridine N atoms, and one amine N atom of the tridentate ligand, one Cl À , and N atom of terminal NCO À . The mononuclear units in 1 are engaged in intermolecular CAHÁ Á ÁO hydrogen bonding leading to 1D chain, which are interlocked through face-to-face pÁ Á Áp interactions resulting in a 2D sheet. The complexes 1-3 exhibit solvatochromism as evidenced from UV-Vis study in different solvent media. They display high-energy intraligand 1 (p-p * ) fluorescence at room temperature and intraligand 3 (p-p * ) phosphorescence in glassy solutions (MeOH at 77 K) and solid states. Electrochemical electron transfer study in MeOH solutions shows a reductive response presumably due to copper(II)-copper(I) couple.