| Popis: |
The main focus of supramolecular chemistry has for a long been put on studying the noncovalent interactions that are responsible for spatial organization of molecules in a system. It has been known that by modifying certain features, such as electron density around potential donors and acceptors of an interaction, it is possible to influence the supramolecular synthesis and to obtain the desired synthon. Supramolecular synthesis in the organic setting has being intensively studied and some synthetic strategies have already been developed. However, it is not a trivial matter to simply transfer those strategies to the metal-organic systems due to the presence of the potentially disruptive counter anions in those settings. The oxime functionalities in metal-free systems has pronounced tendency to link via O–H···N hydrogen bond resulting in the oxime head-to-head R22(6) synthon and the aim of this research was to examine the persistence of this synthon in metal-organic systems, and if we lucky, to derive the means for neutralizing the disruptive effect of the counter-ions that are generally present in those settings. Therefore, we have prepared a series of Cu(II) complexes with trifluoroacetylacetone (tfac) and hexafluoroacetylacetone (hfac) and selected pyridine-based oximes comprising the oxime functionalities at m- and p-positions (4-pyridinealdoxime, 4-Hoxpy ; 4-pyridineketoxime, 4-Meoxpy ; 3-pyridinealdoxime, 3-Hoxpy ; 3-pyridineketoxime, 3-Meoxpy. Complexes were prepared by a solvent assisted mechanochemical synthesis and single crystals were grown from ethanol-dichloromethane solution by slow evaporation. Molecular and crystal structures were determined by SCXRD method. |
