Synthesis and characterization of copper(II)-bis(pyridin-2-carbonyl)amine (pyca)-pseudohalide complexes: 2D superstructure formation through CHO hydrogen bond and ππ interaction in [Cu(pyc

详细信息    查看全文

• 作者：Habibar Chowdhury ; Sk Hafijur Rahaman ; Rajarshi Ghosh ; Sajal Kumar Sarkar ; Hoong-Kun Fun ; Barindra Kumar Ghosh
• 关键词：Copper(II) ; Tridentate ligand ; Supramer ; Luminescence ; Solvatochromism
• 刊名：Journal of Molecular Structure
• 出版年：2007
• 出版时间：29 January 2007
• 年：2007
• 卷：826
• 期：2-3
• 页码：170-176
• 全文大小：596 K

文摘

Three copper(II) complexes of type [Cu(pyca)(Cl)(Y)] (1–3) [pyca = bis(pyridin-2-carbonyl)amine; Y = NCO⁻, N₃⁻, NCS⁻] 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⁻, and N atom of terminal NCO⁻. The mononuclear units in 1 are engaged in intermolecular CHO hydrogen bonding leading to 1D chain, which are interlocked through face-to-face ππ 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(π–π^*) fluorescence at room temperature and intraligand ³(π–π^*) 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.