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Supramolecular self-assembly–directed two unique organogels were achieved by varying gel-immobilized solvents. One gel is comprised of adipic acid (ADP) and triethanolamine (TEA) in pure dimethylformamide medium (i.e., ADP-TEA-DMF), while the other is formed from the combination of adipic acid and triethanolamine in a 1 : 1 mixed solvent system of DMF and acetonitrile (i.e., ADP-TEA-DMF-MeCN). Furthermore, we observed robust crystallization behaviour under the different stoichiometric conditions of adipic acid with triethanolamine in pure dimethylformamide (i.e., Crystal-DMF) and in pure dimethyl sulfoxide (i.e., Crystal-DMSO). To evaluate the mechanical strength and viscoelastic attributes, rheological experiments were executed on these supramolecular organogels of ADP-TEA-DMF and ADP-TEA-DMF-MeCN. Additionally, comprehensive microstructural analyses were conducted in order to unravel the architectural variations arising from the involvement of different solvent-directed semi-solid gel-state. Scanning electron microscopy (FESEM) images of xerogel specimens obtained from the two organogels revealed distinctive morphological patterns. Notably, perceptible variations in the morphology were also observed in both the crystalline phases. The crystal structure of both the crystalline phases (i.e., Crystal-DMF and Crystal-DMSO) were explored using single crystal X-ray diffraction study at 296 K for Crystal-DMF and under liquid nitrogen atmosphere for Crystal-DMSO. Crystal-DMF and Crystal-DMSO have identical crystal structures that are composed of the adipate dianion (ADP2−) and the protonated triethanolamine (TEAH+). The crystal engineering pattern of Crystal-DMSO was elucidated through this study. These findings of versatile organogelation and robust crystallization emphasize the significance of solvent polarity and its diversity in attaining both the gel and crystalline phases. The organogel-formation strategy of ADP-TEA-DMF and ADP-TEA-DMF-MeCN was unravelled using infrared spectroscopic analyses. ESI-Mass spectral studies demonstrate the basic gel-constructing units, which are repeating to offer stable organogels. Thus, the solvent and the gelator concentration-directed organogelation process and the robust crystal-formation strategy are critically visualized in this study. [ABSTRACT FROM AUTHOR]

Four lead(II) complexes featuring pyrazoylisonicotinoylhydrazone ligand paired with various anionic co-ligands (azido, thiocyanato, nitrito, and nitrato) were synthesized and thoroughly examined using structural, analytical, and spectroscopic techniques. These ligands, in their mono-deprotonated state, bind to the lead(II) ion in a tridentate manner through two nitrogen atoms and one oxygen atom. Single-crystal X-ray crystallography revealed the capacity of these molecular complexes to form larger aggregates influenced by the nature of the anion attached to the metal center. In every complex, the lead atom adopts a hemidirectional coordination environment, making it geometrically suited for tetrel bond formation. The crystal structures demonstrate that lead atoms engage in notably short interactions with nitrogen atoms, distances that are shorter than the sum of their van der Waals radii yet exceed the sum of their covalent radii. These tetrel bonds play a pivotal role in weaving the monomeric into self-assembled dimers or extended supramolecular 1D polymers. The formation and characteristics of these intriguing supramolecular structures observed in the solid state of each complex were further explored and validated through density functional theory (DFT) calculations and several computational tools like MEP, NCIPlot, QTAIM, and ELF methods. [ABSTRACT FROM AUTHOR]

The title compound, C15H15NO·0.5H2O, was prepared from α-naphthylamine and 2,4-pentanedione in a 1:1 ratio. An intramolecular N—H...O hydrogen bond in the N-naphthylpent-3-en-2-one molecule involving the amine and carbonyl groups strengthens the structure. The water molecule interacts with two symmetry-related N-naphthylpent-3-en-2-one molecules viaby O—H...O hydrogen bonds.

Two newly designed ligands, [4-chloro-2-((((2-pyridyl)ethyl)imino)methyl)phenol] (HL1) and [4-bromo-2-((((2-pyridyl)ethyl)imino)methyl)phenol] (HL2), have been chosen to synthesize two Cu(II) dimeric Schiff base complexes, [CuL1Cl]2 (1) and [CuL2Cl]2 (2), with the aim of studying their catalytic activity towards oxidation of alcohols by using H2O2 as a terminal oxidant and reduction of nitroarenes by using NaBH4 as a reducing agent. The complexes have been characterized using physicochemical techniques and single crystal X-ray diffraction. DFT calculations of both the complexes have also been performed. Complex [CuL1Cl]2 (1) exhibited a higher catalytic efficiency in each reaction and therefore it was selected for building a magnetically separable catalyst by attaching it to surface modified magnetic nanoparticles. Then, our goal was to modify further complex 1 with iron oxide and isonicotinic acid (ISNA), for easy magnetic separation. The new Fe3O4@ISNA@CuL1 catalyst underwent comprehensive characterization, including FT-IR, SEM, TEM, and PXRD analyses, confirming successful copper complex immobilization on the magnetic nanoparticles. These catalysts maintained stability in aqueous and organic media, enabling alcohol oxidation with H2O2 in acetonitrile and nitroarene reduction with sodium borohydride in an aqueous environment. The surface modification with magnetic nanoparticles facilitated easy separation using an external magnet. The novelty of this work lies in its straightforward preparation, minimal time consumption, reduced use of hazardous chemicals, and cost-effectiveness. The catalysts showed recyclability up to five times without significant loss of activity. Furthermore, our synthesized catalysts demonstrated non-toxicity and environmental friendliness. [ABSTRACT FROM AUTHOR]

Three new PbII complexes [Pb(LI)(SCN)]n, {[Pb(LII)](SCN)}n and {[Pb(HLIII)(SCN)](SCN)}n (HLI = N′-phenyl(pyridin-2-yl)methylene-N-phenylthiosemicarbazide, HLII = N′-amino(pyrazin-2-yl)methylenethiosemicarbazide, HLIII = N′-amino(pyridin-2-yl)methylenethiosemicarbazide) have been synthesized and characterized by spectroscopic techniques and single crystal X-ray diffraction. In all complexes, the corresponding organic ligand behaves as a tridentate N,N′,S-chelating species. A 1D supramolecular polymeric aggregation in complex [Pb(LI)(SCN)]n is dictated by the Pb⋯NCS and Pb⋯S＝C tetrel bonds formed between the [Pb(LI)(SCN)] species. 1D cationic coordination polymers ([Pb(LII)])nn+ in the structure of complex {[Pb(LII)](SCN)}n are linked into a 2D supramolecular polymeric layer through the Pb⋯NCS tetrel bonds and Pb⋯π(NCS) interactions formed with the nitrogen atom and the conjugated system of the free SCN− anions, respectively. The cationic species [Pb(HLIII)(SCN)]+ in the structure of complex {[Pb(HLIII)(SCN)](SCN)}n produce a 1D supramolecular polymer due to the Pb⋯SCN and Pb⋯S＝C tetrel bonds, further stabilized by the Pb⋯π(NCS) interactions formed with the conjugated system of the coordinated NCS− anion. The latter anions also link these 1D chains through the Pb⋯SCN tetrel bonds, yielding 1D supramolecular polymeric ribbons. The energetic relevance of the Pb⋯S and Pb⋯N tetrel bonds has been studied by DFT calculations. The tetrel bonds have been characterized using QTAIM and NCIplot analysis and rationalized using molecular electrostatic potential surface calculations. [ABSTRACT FROM AUTHOR]