What Distinguishes the Strength and the Effect of a Lewis Acid: Analysis of the Gutmann–Beckett Method

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(4)

Published: Nov. 10, 2021

IUPAC defines Lewis acidity as the thermodynamic tendency for pair formation. This strength property was recently specified global (gLA), and is gauged example by fluoride ion affinity. Experimentally, usually evaluated effect on a bound molecule, such induced

Language: Английский

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An easy-to-perform evaluation of steric properties of Lewis acids

Chemical Science, Journal Year: 2023, Volume and Issue: 14(9), P. 2275 - 2288

Published: Jan. 1, 2023

An easy-to-perform approach to assess and quantify steric properties of Lewis acids is reported. The novel LAB-Rep model (Lewis acid/base repulsion model) introduced, which judges in pairs.

Language: Английский

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Modular Design and Bonding Mechanism of Internal Boron–Nitrogen Coordinated Boronic Ester Hydrogels with Alkaline pH Responsiveness and Tunable Gelation pH

Chemistry of Materials, Journal Year: 2023, Volume and Issue: 35(6), P. 2408 - 2420

Published: March 6, 2023

Boronic ester hydrogels have been widely used in biomedical fields for their stimuli responsiveness to multiple disease-related triggers. However, the restricted pH gelation and poor hydrolysis stability limit application variable physiological microenvironments. Here, we report a modular conjugation method designing internal boron–nitrogen coordinated boronic (IBNCB) by constructing polymers with phenylboronic acid or N,N-bis(2-hydroxyethyl) moieties based on amides. Eight distinct IBNCB hydrogel models composed of polymer/polymer polymer/micromolecule were prepared, exhibiting unique alkaline environment, an enhanced stability, bidirectional pH-tunable mechanical properties, lowered tunable gelation. In addition, maintained sol–gel transitional reactive oxygen species (ROS), glucose, temperature. Especially, found that required form ideal should be greater than pKa but lower N,N-bis(2-hydroxyethyl), reducing could pH. The tertiary amine was shown important creation B–N coordination bond, which influenced formation bond. Finally, explored effect main chain's charge gelability proposed dynamic equilibrium mechanism bonds hydrogel. We expect multi-stimuli-responsive will provide new strategy smart materials sensitive physicochemical signals. Furthermore, amide-based exploited generate theoretically limitless number novel including microgels, polymer vesicles, micro–nano particles.

Language: Английский

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Nature and Strength of Lewis Acid/Base Interaction in Boron and Nitrogen Trihalides

Chemistry - An Asian Journal, Journal Year: 2020, Volume and Issue: 15(23), P. 4043 - 4054

Published: Oct. 5, 2020

We have quantum chemically investigated the bonding between archetypical Lewis acids and bases. Our state-of-the-art computations on X3 B-NY3 pairs revealed origin behind systematic increase in B-N bond strength as X Y are varied from F to Cl, Br, I, H. For H3 , trend is driven by commonly accepted mechanism of donor-acceptor [HOMO(base)-LUMO(acid)] interaction. Interestingly, for B-NH3 determined energy required deform BX3 pyramidal geometry it adopts adduct. Thus, that can more easily pyramidalize form stronger bonds with The decrease strain pyramidalization going BF3 BI3 directly caused weakening B-X strength, which stems primarily plane molecule (σ-like) not π system, at variance currently mechanism.

Language: Английский

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The Field of Main Group Lewis Acids and Lewis Superacids: Important Basics and Recent Developments

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 30(1)

Published: Sept. 27, 2023

New developments in the field of Lewis acidity are highlighted, with focus novel acids and superacids group 2, 13, 14, 15 elements. Several important basics, illustrated by modern examples (classification Donor-Acceptor (DA) complexes, amphoteric nature any compound terms DA interactions, reorganization energies main role frontier orbitals) presented discussed. It is emphasized that phenomena general play vital different areas chemistry: from weak "atomophilic" interactions to complexes superacids.

Language: Английский

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Predicting Lewis Acidity: Machine Learning the Fluoride Ion Affinity of p‐Block‐Atom‐Based Molecules

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(17)

Published: March 7, 2024

Abstract “How strong is this Lewis acid?” a question researchers often approach by calculating its fluoride ion affinity (FIA) with quantum chemistry. Here, we present FIA49k, an extensive FIA dataset 48,986 data points calculated at the RI‐DSD‐BLYP‐D3(BJ)/def2‐QZVPP//PBEh‐3c level of theory, including 13 different p ‐block atoms as accepting site. The FIA49k was used to train FIA‐GNN, two message‐passing graph neural networks, which predict gas and solution phase values molecules excluded from training mean absolute error 14 kJ mol −1 ( r 2 =0.93) SMILES string acid only input. accuracy notable, given wide energetic range 750 spanned FIA49k. model's value demonstrated four case studies, predictions for extracted Cambridge Structural Database reproducing results catalysis research available in literature. Weaknesses model are evaluated interpreted chemically. FIA‐GNN can be reached via free web app www.grebgroup.de/fia‐gnn ).

Language: Английский

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In-silico-assisted derivatization of triarylboranes for the catalytic reductive functionalization of aniline-derived amino acids and peptides with H2

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 7, 2024

Cheminformatics-based machine learning (ML) has been employed to determine optimal reaction conditions, including catalyst structures, in the field of synthetic chemistry. However, such ML-focused strategies have remained largely unexplored context catalytic molecular transformations using Lewis-acidic main-group elements, probably due absence a candidate library and effective guidelines (parameters) for prediction activity elements. Here, construction triarylborane its application an ML-assisted approach reductive alkylation aniline-derived amino acids C-terminal-protected peptides with aldehydes H

Language: Английский

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Acidity of Isomorphic Substituted Zeolites with B, Al and Ga Revisited

ChemPhysChem, Journal Year: 2024, Volume and Issue: 25(9)

Published: Feb. 14, 2024

Abstract Isomorphic substitution of zeolites with B, Al and Ga is a widely used approach in catalysis. The experimentally reported trend their acidities decreases the order: Al>Ga>B. However, consistent explanation still lacking literature. To bring more understanding this trend, density functional theory computations were conducted on several model systems. First, acidity small clusters two (2T) five (5T) tetrahedral sites was analyzed. These systems then projected onto three large void structures: H‐[A]‐BEA (52T), H‐[A]‐FAU (84T) H‐[A]‐MOR (112T) A=B, Al, Ga. Our electron Interacting Quantum Atom analyses show that originates from much stronger O−Al bond, which dominated by electrostatic attraction. bridging hydroxyl therefore donates charge to metal, proton becomes positive consequently acidic. are acidic than B due greater covalent nature O−Ga bond. resulting acidity, as seen ammonia, depends both oxygen distribution surrounding oxygens exerted substituents.

Language: Английский

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Deciphering the Purification Additive Chemistries for Ultra‐Stable High‐Voltage Lithium‐Ion Batteries

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 25, 2025

Abstract Hydrogen fluoride (HF)‐induced degradation of electrode materials and interphases presents a significant challenge for high‐voltage Li‐ion batteries. However, progress in developing advanced HF‐scavenging additives is hindered by limited understanding HF‐elimination reactions the absence robust design principle. Herein, it proposed to analyze energy decomposition analysis 24 elucidate underlying mechanism identify key factors influencing HF‐additives reactions. The findings reveal that orbital contribution ratio (OCR) critical determinant chemical bonding HF‐additive Specifically, an 80% OCR H + 53% F − are essential completing HF elimination. Based on these insights, general principle designing effective heptamethyldisilazane as particularly well‐suited candidate, exhibiting optimal both ions identified. Remarkably, addition just 1 wt.% HMDS significantly eliminats HF, inhibiting cathode‐to‐anode crosstalk behaviors limiting interphase degradation. This guardian endows graphite/LiNi 0.8 Co 0.1 Mn O 2 pouch cells with performance improvement, achieving capacity retention over 2528 cycles, substantial improvement compared 1139 cycles observed without additive. study provides valuable insights electrolyte high‐performance

Language: Английский

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The Role of Donor Species and Heteroatom Electron Delocalization on Additive Interactions with Methylammonium Lead Iodide

ACS Omega, Journal Year: 2025, Volume and Issue: 10(16), P. 16705 - 16716

Published: April 18, 2025

Additive engineering-the incorporation of small organic molecules during film deposition or as a postfabrication step-is common strategy for regulating crystallization kinetics passivating defects the fabrication metal halide perovskite films. However, much these efforts have been based on chemical intuition, leaving limited understanding how molecular structure influences interactions with surfaces. This paper describes using heterocyclic model system to probe effects heteroatomic species (N, O, S, Se, and P) heteroatom electron delocalization additive PbI2-rich (100) surface MAPbI3 density functional theory (DFT) calculations. For all studied, we observe that adsorption energies (or interaction strength) surfaces increase (i.e., degree unsaturation) decreases. We are strongest N-donors weakest O-donors, P-, S-, Se-donors having in between, describable by correlation charge two different regimes. The electronegativity plays critical role, dictating extent transfer from Pb adsorbate, increasing correlated lower reduction possibly oxidation case O-donors). Heteroatom is also predictive band gap shifting, more electronegative donors gaps; conversely, low P-donors typically results reductions.

Language: Английский

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