engleski

Copper(II) halice complexes with pyridine-oxime ligands

The first task to be achieved in reaching the main goal of the crystal engineering is targeting a specific supramolecular topology. Recently, a protocol for supramolecular synthesis of one-dimensional (1-D) chains, that comprise octahedral metal-complexes linked via predictable hydrogen bonds, has been established through fine-tuning electrostatic molecular-recognition events. In this study we wanted to extend our previous findings, and examine the impact of different metal cations and counter ions on the resulting supramolecular outcome. Therefore, we opted for copper(II) ions in a combination with different halides anions, while keeping the same set of organic ligands constant. Here again, we used the 4-pyridineketoxime, 4-Meoxpy ; 3-pyridineketoxime, 3-Meoxpy, as this particular functionality is capable of making directional hydrogen bonds while having a smaller potential towards coordination to metal centres. In metal-free systems it shows a pronounced tendency to forming head-to-head dimeric synthons. Here we report on mapping out the supramolecular landscape of this class of compounds with the aim to define supramolecular synthetic conditions for preserving the oxime head-to-head R22(6) motifs in linking metal complexes. Although our first attempts did not result in the targeted supramolecular linkage, a fine-tuning of our reactants at a later synthetic step finally produced the desired supramolecular outcome-the oxime head-to-head dimers.

crystal engineering ; supramolecular ; copper(II) ; 4-pyridineketoxime ; 4-Meoxpy ; 3-pyridineketoxime ; 3-Meoxpy

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