A convenient method for the synthesis of silver alkynyl compounds containing different nuclearities has been developed. The reaction of AgC[triple bond, length as m-dash]CBu(t) and AgX (X = CF3CO2(-), C2F5CO2(-)) in the presence of auxiliary ligands L (L = bipyridine, bipy; 1,10-phenanthroline, phen; 2-(diphenylphosphino)pyridine, dppy) under different conditions afforded a family of new silver alkynyl compounds, namely, [Ag3(bipy)(C[triple bond, length as m-dash]CBu(t))(CF3CO2)2]n (), [Ag4(bipy)2(C[triple bond, length as m-dash]CBu(t))(CF3CO2)3]n (), [Ag6(phen)3(C[triple bond, length as m-dash]CBu(t))2(C2F5CO2)4(MeOH)(EtOH)] (), [Ag8L4(C[triple bond, length as m-dash]CBu(t))2(C2F5CO2)6] (L = bipy, ; L = phen, ), [Ag10(dppy)2(C[triple bond, length as m-dash]CBu(t))6X4] (X = CF3CO2(-), ; X = C2F5CO2(-), ), [Ag12(bipy)2(C[triple bond, length as m-dash]CBu(t))8(C2F5CO2)4] () and [Ag12(phen)4(C[triple bond, length as m-dash]CBu(t))6(CF3CO2)6]·2EtOH (). Single-crystal X-ray analysis revealed that compounds and display infinite-chain structures, while the other seven compounds are discrete molecules containing silver nuclearities varying from 6 to 12. The formation of various structural motifs depends on the reactant ratios and the ligands/anions with different nature.
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J Am Heart Assoc
January 2025
Department of Population Health Sciences Weill Cornell Medicine New York NY.
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View Article and Find Full Text PDFChemphyschem
January 2025
University of Namur, Department of Chemistry, Rue de Bruxelles, 61, 5000, Namur, BELGIUM.
The [4+2] Diels-Alder cycloaddition reaction between 2,5-DMF (1) and ethylene derivatives (2a-h) activated by electron-withdrawing groups has been studied at the density functional theory levels using a panoply of tools to unravel the reaction mechanisms. From the analysis of the reactivity indices, 2a-h behave as electrophiles while 1 as nucleophile, and the activation of the double bond of ethylene increases its electrophilicity, which is accompanied by an enhancement of the polarity of the reaction. The activation Gibbs free energy decreases linearly as a function of this increase of polarity, as estimated by the electrophilicity difference between the reactants.
View Article and Find Full Text PDFJ Org Chem
January 2025
Division of Theoretical Chemistry, IFM, Linköping University, 58183 Linköping, Sweden.
The harmonic oscillator model of aromaticity (HOMA) offers a straightforward route to quantifying aromaticity that requires no other information than the bond lengths of the conjugated ring in question. Given that such information is often readily obtainable from quantum-chemical calculations, it is pertinent to improve this parametrized model as much as possible. Here, a new version of HOMA is presented where, atypically, the corresponding parameters are derived from the actual bond lengths of both aromatic and antiaromatic (rather than nonaromatic) reference compounds, as calculated with a high-level method.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264000, China.
Constructing multifunctional phosphors grounded in the intricate relationship between energy level structures and luminescent properties has captivated researchers in the luminescent material field. Herein, using the embedded cluster multiconfigurational ab initio method, the energy levels of Bi in the SrLaGaO host at different geometries were calculated, which results in the establishment of complete configurational coordinate curves, yielding breathing mode vibrational frequencies and equilibrium bond lengths for all excited states. These curves supply deep insight into the luminescence properties of Bi-doped phosphors and highlight the impact of ions in the second coordination sphere on luminescence.
View Article and Find Full Text PDFJ Chem Phys
January 2025
Department of Chemistry and Biochemistry, University of Texas at El Paso, El Paso, Texas 79968, USA.
This study investigates the impact of structural isomerism on the excited state lifetime and redox energetics of heteroleptic [Ir(ppy)2(bpy)]+ and homoleptic Ir(ppy)3 photoredox catalysts using ground-state and time-dependent density functional theory methods. While the ground- and excited-state reduction potentials differ only slightly among the isomers of these complexes, our findings reveal significant variations in the radiative and non-radiative decay rates of the reactivity-controlling triplet 3MLCT states of these closely related species. The observed differences in radiative decay rates could be traced back to variations in the transition dipole moment, vertical energy gaps, and spin-orbit coupling of the isomers.
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