Nanosized chiral octahedral M coordination cages were prepared self-assembly of sulfonylcalix[4]arene tetranuclear M(II) clusters (M = Co or Ni) with enantiomerically enriched linkers based on tris(dipyrrinato)cobalt(III) complexes, appended with peripheral carboxylic groups. Two pairs of enantiomers of cages were obtained and unambiguously characterized from a structural point of view, using single crystal X-ray diffraction. Chiral-HPLC was used to evidence the enantiomers.
View Article and Find Full Text PDFPhys Chem Chem Phys
December 2024
The rational design of organic ligands with the aim to control their binding abilities towards different metal ions can be considered as one of the key concepts in supramolecular coordination chemistry. Regarding the macrocyclic compounds of thiacalix[4]arene family, this can be achieved the targeted modulation of macrocyclic platform rigidity as well as the proper choice of appended binding sites. Four macrocyclic salen-type ligands based on lower rim disubstituted thiacalix[4]arene derivatives, adopted in a cone conformation, bearing highly coordinating iminophenolic or catecholic groups and two -CH- moieties as spacers but presenting different abilities to form H-bonds, were chosen to elucidate the interplay between the conformational flexibility of the macrocyclic ligands, propensity to participate in the intermolecular H-bonding and the extraction ability of 3d-metal cations.
View Article and Find Full Text PDFA series of four new Dy dodecanuclear clusters based on azobenzene derivative ligands of salicylic acid (-) has been synthesized and characterized in the crystalline phase using X-ray diffraction on single crystal and powder, IR spectroscopy, elemental analysis, and DSC-TGA methods. It was revealed that all obtained clusters exhibit the formation of the similar metallic cluster nodes, as vertex-sharing heterocubanes, obtained from four Dy cations, three bridging hydroxyl groups, and O atoms from the salicylic ligands. The coordination geometry around the Dy(III) centers has been carefully analyzed.
View Article and Find Full Text PDFContext: The molecular design of spatially preorganized molecules is one of the critical issues in organic chemistry. Molecular recognition and multipoint binding define them. They organize nanoscale assemblies and devices and stably form host-guest inclusion complexes.
View Article and Find Full Text PDFA series of new 2-hydroxy-3-methoxybenzylidenethiazolo[3,2-]pyrimidines with different aryl substituents at the 5 position are synthesized and characterized by H/ C NMR and IR-spectroscopy and mass-spectrometry, as well as single crystal X-ray diffraction (SCXRD). It was demonstrated that the type of hydrogen bonding can play a key role in the chiral discrimination of these compounds in the crystalline phase. The hydrogen bond of the O-H.
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