Synthesis, characterisation of a complex of Cu(II) with a multidentate macrocyclic ligand and its interactions with anions
摘要:
A macrocyclic ligand possessing a donor set of {N3S2} synthesised via Cs+-templation, 4-(pyridin-2-ylmethyl)-1,7-dithia-4,10-diazacyclododecane (L) and its Cu(II) complex, [CuL(NCMe)](2+) (6), are described. This Cu(II) complex interacts with a range of anions, F-, Cl-, Br-, I-, HCOO-, AcO-, CO32-, NO3-, C2O42-, H2PO4- , SCN-, CN-, BF4-. Of the investigated anions, I-, SCN-, and CN-, show strong interaction with the Cu(II) centre as indicated by their spectral variations. The iodide particularly demonstrates distinct change in colour. This change originates from a newly appeared band at 471 nm upon iodide binding, which arises from the ligand (I-) to Cu(II) charge transfer (LMCT) in the iodide-substituted Cu(II) complex, [CuLI](+) (7). All organic compounds are characterised by NMR spectroscopy and/or microanalysis. The identities of the two Cu(II) complexes are confirmed by using microanalysis and the complex 6 is crystallographically analysed. (C) 2009 Elsevier B. V. All rights reserved.