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            The title compound, C6H13N2+·Cl−, is as an amidinium salt that was isolated as unexpected product from the reaction between acetonitrile, chloroform and pyrrolidine under refluxing conditions. The packing features two N—H...Cl hydrogen bonds to generate centrosymmetric tetramers (two cations and two anions) and van der Waals interactions.more » « less
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            Bis(triphenylsulfonium) tetrachloridomanganate(II), (C18H15S)2[MnCl4] (I), triphenylsulfonium tetrachloridoferrate(III), (C18H15S)[FeCl4] (II), and bis(triphenylsulfonium) tetrachloridocobaltate(II), (C18H15S)2[CoCl4] (III), crystallize in the monoclinic space groupsP21/n[(I) and (III)] andP21/c[(II)]. Compounds (I) and (III) each contain two crystallographically independent triphenylsulfonium (TPS+) cations in the asymmetric unit, whereas (II) has one. In all three compounds, the sulfonium centers adopt distorted trigonal–pyramidal geometries, with S—C bond lengths falling roughly in the 1.78–1.79 Å range and C—S—C angles observed at about 101 to 106°. The [MCl4]n−anions (M= Mn2+, Fe3+, Co2+;n= 2,1,2) adopt slightly distorted tetrahedral geometries, withM—Cl bond lengths in the 2.19–2.38 Å range and Cl—M—Cl angles of approximately 104–113°. Hirshfeld surface analyses shows that H...H and H...C contacts dominate the TPS+cation environments, whereas H...Cl and shortM—S interactions link each [MCl4]n−anion to the surrounding cations. In (I) and (III), inversion-centered π–π stacking further consolidates the crystal packing, while in (II) no π–π interactions are observed.more » « lessFree, publicly-accessible full text available August 1, 2026
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            Bis(triphenylsulfonium) tetrachloridozinc(II), (C18H15S)2[ZnCl4] (I), bis(triphenylsulfonium) tetrachloridocadmium(II), (C18H15S)2[CdCl4] (II), and bis(triphenylsulfonium) tetrachloridomercury(II) methanol monosolvate, (C18H15S)2[HgCl4]·CH3OH (III), each crystallize in the monoclinic space groupP21/n. In all three structures, there are two crystallographically independent triphenylsulfonium (TPS) cations per asymmetric unit, each adopting a distorted trigonal–pyramidal geometry about the S atom (S—C bond lengths in the 1.77–1.80 Å range and C—S—C angles of 100–107°). The [MCl4]2–anions (M= Zn2+, Cd2+, Hg2+) are tetrahedral; their M—Cl bond lengths systematically increase from Zn2+to Hg2+, consistent with the larger ionic radius of the heavier metal. Hirshfeld surface analyses show that H...H and H...C contacts dominate the TPS cation environments, whereas H...Cl and S...Minteractions anchor each [MCl4]2–anion to two surrounding TPS cations. Weak C—H...Cl hydrogen bonds, as well as inversion-centered π–π stacking, generate layers in (I) and (II) and dimeric [(TPS)2–HgCl4]2assemblies in (III).more » « lessFree, publicly-accessible full text available April 1, 2026
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            The reactions of triphenylsulfonium chloride ([TPS][Cl]) with various acids in methanol yield the corresponding salts triphenylsulfonium triiodide, C18H15S+·I3−or [TPS][I3] (I), triphenylsulfonium perchlorate, C18H15S+·ClO4−or [TPS][ClO4] (II), and triphenylsulfonium hexafluorophosphate, C18H15S+·PF6−or [TPS][PF6] (III), as crystalline products. These crystals were structurally characterized by single-crystal X-ray diffraction. In all three compounds, the sulfur atom in the triphenylsulfonium cation adopts a distorted trigonal–pyramidal geometry. [TPS][I3] (I) and [TPS][PF6](III) both crystallize in the space groupP21/n, while [TPS][ClO4] (II) crystallizes inP21. The S—C bond lengths are comparable across the three salts, and the S—C—S bond angles are consistently between 102 and 106°. Hirshfeld surface analyses reveal that each structure is dominated by hydrogen-based intermolecular contacts, supplemented by anion-specific interactions such as I...H in (I), O...H in (II), and F...H in (III). These contacts organize the ions into mono-periodic ribbon- or chain-like arrangements. No significant π–π stacking is observed.more » « lessFree, publicly-accessible full text available February 1, 2026
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            The reaction of 2-(1H-pyrrol-1-yl)ethanol with 3-hydroxyflavone in the presence of copper(II) bromide yielded a dimeric copper(II) complex, [μ-O-(κ2-O,O-flav)(κ2-N,O-2PEO)Cu]2 (1) (flav = 3-hydroxyflavonolate; 2PEO = 2-(1H-pyrrol-1-yl)ethanolate) with both the flav and 2PEO ligands bound to the copper(II) atom in a κ2-bonding mode. The dimer is held electrostatically by bridging oxygen atoms between two copper atoms. Complex 1 was characterized by single-crystal X-ray diffraction, infrared, and UV-Vis spectroscopy, elemental analysis, and melting point determination. The complex crystallizes in the monoclinic space group P21/n (14) with cell values of a = 11.85340(10) Å, b = 8.51480(10) Å, c = 23.8453(2) Å; β = 99.3920(10)°.more » « less
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            Diisoamyl (1R,4S)-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate (2) was prepared by reacting exo-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride (1) with isoamyl alcohol in the presence of a sulfuric acid catalyst under sonication conditions. Compound 2 was characterized by 1H, 13C NMR, DEPT-135, infrared, and UV-vis spectroscopy. Gas chromatography–mass spectrometry, elemental analysis, and melting point determination were used to assess purity. The structure of compound 2 was also determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group P21/c (14) with cell values of a = 15.5647(3) Å, b = 12.8969(2) Å, c = 9.0873(2) Å; β= 99.3920(10)°.more » « less
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            A 1,2,3-triazole-based chemosensor is used for selective switching in logic gate operations through colorimetric and fluorometric response mechanisms. The molecular probe synthesized via “click chemistry” resulted in a non-fluorescent 1,4-diaryl-1,2,3-triazole with a phenol moiety (PTP). However, upon sensing fluoride, it TURNS ON the molecule’s fluorescence. The TURN-OFF order occurs through fluorescence quenching of the sensor when metal ions, e.g., Cu2+, and Zn2+, are added to the PTP-fluoride ensemble. A detailed characterization using Nuclear Magnetic Resonance (NMR) spectroscopy in a sequential titration study substantiated the photophysical characteristics of PTP through UV-Vis absorption and fluorescence profiles. A combination of fluorescence OFF-ON-OFF sequences provides evidence of 1,2,3-triazoles being controlled switches applicable to multimodal logic operations. The “INH” gate was constructed based on the fluorescence output of PTP when the inputs are F− and Zn2+. The “IMP” and “OR” gates were created on the colorimetric output responses using the probe’s absorption with multiple inputs (F− and Zn2+ or Cu2+). The PTP sensor is the best example of the “Write-Read-Erase-Read” mimic.more » « less
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