We have quantum chemically investigated the bonding between archetypical Lewis acids and bases. Our state-of-the-art computations on the X B-NY Lewis pairs have revealed the origin behind the systematic increase in B-N bond strength as X and Y are varied from F to Cl, Br, I, H. For H B-NY , the bonding trend is driven by the commonly accepted mechanism of donor-acceptor [HOMO(base)-LUMO(acid)] interaction. Interestingly, for X B-NH , the bonding mechanism is determined by the energy required to deform the BX to the pyramidal geometry it adopts in the adduct. Thus, Lewis acids that can more easily pyramidalize form stronger bonds with Lewis bases. The decrease in the strain energy of pyramidalization on going from BF to BI is directly caused by the weakening of the B-X bond strength, which stems primarily from the bonding in the plane of the molecule (σ-like) and not in the π system, at variance with the currently accepted mechanism.
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http://dx.doi.org/10.1002/asia.202001127 | DOI Listing |
J Am Chem Soc
January 2025
School of Chemistry and Chemical Engineering, Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, Shandong University, Jinan 250100, P. R. China.
Herein, we describe a hexavalent tellurium-based chalcogen bonding catalysis platform capable of addressing reactivity and selectivity issues. This research demonstrates that hexavalent tellurium salts can serve as a class of highly active chalcogen bonding catalysts for the first time. The tellurium centers in these hexavalent catalysts have only one exposed interaction site, thus providing a favorable condition for the controlling of reaction selectivity.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Texas A&M University, Department of Chemistry, Texas A&M University, 77842, College Station, UNITED STATES OF AMERICA.
Lewis acids play a central role in a large variety of chemical transformations. The reactivity of the strongest Lewis acids is typically studied in the context of affinity towards hard bases, such as fluoride or oxygenous species. Carbocations can be viewed as soft Lewis acids, possessing significant affinity for softer bases, such as hydride.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
USTC: University of Science and Technology of China, Department of Chemistry, No. 96 Jinzhai Road, 230026, Hefei, CHINA.
The synthesis of metal-organic frameworks (MOFs) by low energy input has been a long-term target for practical applications yet remains a great challenge. Herein, we developed a low-energy MOF growth strategy at a temperature down to 50 °C by simply introducing seeds into the reaction system. The MOFs are continuously grown on the surface of the seeds at a growth rate dozens of times higher than that of conventional solvothermal synthesis at low temperature, while the resulting MOFs possess high crystallinity, porosity, and stability similar to solvothermal seeds.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Western University, Chemistry, 1151 Richmond Street, N6A3K7, London, CANADA.
This work addresses fundamental questions that deepen our understanding of secondary coordination sphere effects on carbon dioxide (CO2) reduction using derivatized hydride analogues of the type, [Cp*Fe(diphosphine)H] (Cp* = C5Me5-) - a well-studied family of organometallic complex - as models. More precisely, we describe the general reactivity of [(Cp*-BR2)Fe(diphosphine)H], which contains an intramolecularly positioned Lewis acid, and its cooperative reactivity with CO2. Control experiments underscore the critical nature of borane incorporation for CO2 to reduced products, a reaction that does not occur for unfunctionalized [Cp*Fe(diphosphine)H]).
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, United States.
The viability of the P═Se bond to serve as a monitor of the strength of a noncovalent bond was tested in the context of the (CH)PSe molecule. Density functional theory (DFT) computations paired this base with a collection of Lewis acids that spanned hydrogen, halogen, chalcogen, pnicogen, and tetrel bonding interactions and covered a wide range of bond strengths. A very strong linear correlation was observed between the interaction energy and the nuclear magnetic resonance (NMR) J(PSe) coupling constant, which could serve as an accurate indicator of bond strength.
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