| Summary: | New Schiff base complexes [Cu<sub>2</sub>(HL<sup>1</sup>)(L<sup>1</sup>)(N<sub>3</sub>)<sub>3</sub>]∙2H<sub>2</sub>O (<b>1</b>) and [Cu<sub>2</sub>L<sup>2</sup>(N<sub>3</sub>)<sub>2</sub>]∙H<sub>2</sub>O (<b>2</b>) were synthesized. The crystal structures of <b>1</b> and <b>2</b> were determined by single-crystal X-ray diffraction analysis. The HL<sup>1</sup> ligand results from the condensation of salicylaldehyde and 1-(2-aminoethyl)piperazine, while a new organic ligand, H<sub>2</sub>L<sup>2</sup>, was formed by the dimerization of HL<sup>1</sup> via a coupling of two piperazine rings of HL<sup>1</sup> on a carbon atom coming from DMF solvent. The dinuclear building units in <b>1</b> and <b>2</b> are linked into complex supramolecular networks through hydrogen and coordination bondings, resulting in 2D and 1D architectures, respectively. Single-point and broken-symmetry DFT calculations disclosed negligible singlet–triplet splittings within the dinuclear copper fragments in <b>1</b> and <b>2</b>. Catalytic studies showed a remarkable activity of <b>1</b> and <b>2</b> towards cyclohexane oxidation with H<sub>2</sub>O<sub>2</sub> in the presence of nitric acid and pyridine as promoters and under mild conditions (yield of products up to 21%). Coordination compound <b>1</b> also acts as an active catalyst in the intermolecular coupling of cyclohexane with benzamide using di-tert-butyl peroxide (<i><sup>t</sup></i>BuOO<i><sup>t</sup></i>Bu) as a terminal oxidant. Conversion of benzamide at 55% was observed after 24 h reaction time. By-product patterns and plausible reaction mechanisms are discussed.
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