| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1335098 | Polyhedron | 2009 | 10 Pages |
A new tridentate N2O donor Schiff base ligand [(C6H5C(OH)CHC(CH3)NCH2C5H4N)LH] was obtained by 1:1 condensation of benzoylacetone with 2-picolylamine and has been used to synthesise a mononuclear [CuLCl] (1) and an end-to-end dicyanamide bridged polynuclear {[Cu2(μ-L)2(μ2-1,5-(CN)2N)]ClO4}n (2) copper(II) complexes. The ligand, 1 and 2 were clearly characterised by elemental analysis, FT-IR, 1H NMR, UV–Vis spectral studies, electrochemical studies and in addition single crystal X-ray diffraction studies were performed for 1 and 2. The Schiff base ligand [LH] shows a significant variation in its coordination behaviour with copper(II) ion in absence and in presence of dicyanamide ion in 1 and 2 respectively. In absence of dicyanamide the deprotonated enolato oxygen of the tridentate Schiff base ligand [L]− coordinates the copper(II) ion in a monodentate fashion generating a mononuclear species (1) whereas in presence of the dicyanamide ion, the deprotonated enolato oxygen of [L]− bridges two adjacent [CuL(CN)2N] units through μ-OL bridges, forming dimers. The dimeric units are further linked to adjacent dimeric units through μ2-1,5-dicyanamide bridges to produce 1D polymeric chains in 2. Variable temperature magnetic susceptibility measurements for 2 in the temperature range 2-300 K reveal the presence of weak antiferromagnetic exchange interactions in the polymeric chain.
Graphical abstractA new tridentate N2O donor Schiff base ligand was obtained by 1:1 condensation of benzoylacetone with 2-picolylamine and has been used to synthesise a mononuclear [CuLCl] (1) and an end-to-end dicyanamide bridged polynuclear {[Cu2(μ-L)2(μ2-1,5-(CN)2N)]ClO4}n (2) copper(II) complexes. The Schiff base ligand [LH] shows a significant variation in its coordination behaviour with copper(II) ion in absence and in presence of dicyanamide ion in 1 and 2 respectively. Variable temperature magnetic susceptibility measurements for 2 in the temperature range 2-300 K reveal the presence of weak antiferromagnetic exchange interactions in the polymeric chain.Figure optionsDownload full-size imageDownload as PowerPoint slide
