One-dimensional chain copper(II) complex: Synthesis, X-ray crystal structure and catalytic activity in the epoxidation of styrene

Two new copper(II) complexes, [Cu(HL1)(NO3)] (1) (H2L1 = 1-(N-ortho-hydroxyacetophenimine)-ethane-2-ol) and f[Mg(H2O)(6)][Cu(PYdca)(2)]center dot 2H(2)O)]n (2) (H(2)pydca = 2,5-pyridine dicarboxylic acid) have been synthesized and characterized. X-ray crystal structure analysis reveals that the geometry of complex 1 is square planar, where copper(II) centers are linked through a weak coordination by the nitrate 0 atoms occupying two axial positions, resulting a helical chain structure. Complex 1 crystallizes in the chiral space group P2(1). There is no chiral center in the Schiff-base ligand of 1, its helical structure develops due to the formation of a NO3- bridged chain through an asymmetric arrangement. Complex 2 is a ID chain in which the copper(II) ions are connected by bridging carboxylato ligands. The [Mg(H2O)(6)](2+) moiety occupies the inter-chain space. Epoxidation reactions of styrene and substituted styrenes are homogeneously catalyzed by complexes 1 and 2 with H2O2 as the oxidant. (C) 2012 Elsevier Ltd. All rights reserved.