Advances and Prospects in Understanding London Dispersion Interactions in Molecular Chemistry

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(12)

Published: Dec. 5, 2023

London dispersion (LD) interactions are the main contribution of attractive part van der Waals potential. Even though LD effects driving force for molecular aggregation and recognition, role these omnipresent in structure reactivity had been largely underappreciated over decades. However, recent years considerable efforts have made to thoroughly study their potential as a chemical design element structures catalysis. This was possible through fruitful interplay theory experiment. review highlights results advances utilizing structural motif understand utilize intra- intermolecularly LD-stabilized systems. Additionally, we focus on quantification fundamental reactions.

Language: Английский

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Quantifying interactions in the active encounter complex of frustrated Lewis pairs

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: April 17, 2025

Abstract Sustainable catalysts based on main-group elements, such as frustrated Lewis pairs (FLPs), have emerged alternatives to precious metal systems. The initial reaction of the acid, base and small molecule ( e.g . H 2 ) is formally termolecular, but rationalised by pre-association acid in an encounter complex. Here we show that charge-transfer band between P(mes) 3 B(C 6 F 5 can be analysed supramolecular UV-vis spectroscopic techniques provide key thermodynamic parameter, association constant K a ), for active complex, i.e pre-associated complex specifically correct orientation small-molecule activation. We also demonstrate higher concentration solution leads faster activation hydrogen. This method enables researchers directly probe underpins FLP subsequent catalysis, will aid design more sustainable catalysts.

Language: Английский

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Remote Back Strain: A Strategy for Modulating the Reactivity of Triarylboranes

Synlett, Journal Year: 2023, Volume and Issue: 34(18), P. 2187 - 2192

Published: June 14, 2023

Abstract A strategy for modulating the Lewis acidity of triarylboranes is proposed based on concept remote back strain. Steric repulsion and noncovalent interactions, both generated between aryl meta-substituents triarylboranes, are found to be critical determining strength Applying this concept, we synthesized B[2,6-F2-3,5-(TMS)2-C6H]3 liquid B[2,6-F2-3,5-(allyl)2-C6H]3 demonstrated their superior catalytic activity hydrogenation quinoline relative B(C6F5)3 or B(2,6-F2C6H3)3. Moreover, established first example by using in presence a gaseous 1:1:1 molar mixture H2, CO, CO2.

Language: Английский

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Recent Trends in Triarylborane Chemistry: Diversification of Structures and Reactivity via meta-Substitution of the Aryl Groups

Synthesis, Journal Year: 2024, Volume and Issue: 56(22), P. 3421 - 3430

Published: Aug. 19, 2024

Abstract This Short Review summarizes the synthesis and applications of triarylboranes (BAr3), including both homoleptic heteroleptic species, with a focus on modification their electronic structural properties via introduction meta-substituents respect to B atoms Ar groups. approach constitutes complementary alternative conventional strategies for design BAr3, which are usually based ortho- and/or para-substituents. An initial analysis revealed that CH3 F most common in hitherto reported BAr3 (apart from H atom). Thus, an extensive exploration other substituents, e.g., heavier halogens, longer or functionalized alkyl groups, aryl will increase our knowledge structure reactivity eventually lead range new applications. 1 Introduction 2 Scope this 2.1 The Electronic Steric Influence meta-Substituents 2.2 Molecular Transformations Mediated by meta-Substituted Boranes 2.3 Other Examples meta-Functionalization 3 Conclusions Perspectives

Language: Английский

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The Active Encounter Complex in Frustrated Lewis Pair Chemistry

Published: Aug. 30, 2023

Sustainable catalysts based on main-group elements have emerged as alternatives to expensive and environmentally unfriendly precious metal systems. Frustrated Lewis pairs (FLPs) are precluded from forming a classical adduct, displayed remarkably versatile reactivity in the fields of small-molecule activation catalysis. The initial reaction acid, base small molecule (e.g. H2) is formally termolecular, but viability this rationalised by pre-association acid an encounter complex. However, there no experimental methodology study active complex, i.e. pre-associated complex that correct orientation for activation. Here we show charge-transfer band between PMes3 B(C6F5)3 can be analysed supramolecular techniques provide key thermodynamic parameter, Ka, We also demonstrate higher concentration solution leads faster hydrogen. This method enables researchers directly probe underpins FLP subsequent catalysis, will aid design more sustainable catalysts.

Language: Английский

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Molecular Wind-Up Meter for the Quantification of London Dispersion Interactions

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 57(2), P. 257 - 266

Published: Dec. 22, 2023

ConspectusThe experimental quantification of interactions on the molecular level provides necessary basis for design functional materials and chemical processes. The interplay multiple parameters small quantity individual pose a special challenge such endeavors. common method is use balances, which can exist in two different states. Thereby, stabilizing interaction occur one states, favoring its formation thus affecting thermodynamic equilibrium system. One determining change this since various analytical methods could not be applied to fast-changing equilibria. A new promising quantifying Molecular Wind-up Meters (MWM) kinetics, rather than effect thermodynamics, investigated. An MWM transformed with an energy input (e.g. irradiation) into metastable state. Then, rate thermal transformation back ground state measured. strength present controls kinetics reactions, allowing direct correlation. advantage approach lies high sensitivity (energy differences larger by 1 order magnitude) and, general, allows broader range solvents methods. Azobenzene-based has been established as powerful tool quantify London dispersion interactions. (LD) represents attractive part van der Waals potential. Although neglected past due weak character, it shown that influence LD structure, stability, reactivity matter decisive. Especially molecules, contribution increases overproportionately number atoms, sparked increasing interest so-called donors (DED) structural element. Application azobenzene-based only allowed differentiation bulkiness, but also systematically addressed length n-alkyl chains. Additionally, solvent was studied. Based azobenzene MWM, increment system proposed, rough estimate specific DED.

Language: Английский

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A crystallized view of acid-base chemistry

Science, Journal Year: 2024, Volume and Issue: 385(6714), P. 1165 - 1166

Published: Sept. 12, 2024

The structural relationship between Lewis adduct isomers is resolved

Language: Английский

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Triarylborane Catalysis: From Hydrogenation of Unsaturated Molecules to H₂ Purification

Journal of Synthetic Organic Chemistry Japan, Journal Year: 2024, Volume and Issue: 82(11), P. 1097 - 1106

Published: Nov. 1, 2024

Herein we summarize our recent progress on the design, synthesis, and catalytic application of triarylboranes. We demonstrated that structurally well-characterized triarylboranes catalyzed hydrogenation N-heteroaromatics carbonyl compounds when crude H2 (a mixture H2, CO, CO2, CH4) was directly used as reductant. In addition, proposed a concept 'remote back strain' to finely tune Lewis acidity by regulating stability base-borane adducts via an intramolecular repulsion between meta-substituents aryl groups. Such approaches were eventually combined with machine learning efficiently assisted optimization boranes reductive alkylation multiply-substituted aniline derivatives, including amino acids peptides, using These results manifest new aspect main-group catalysis beyond its simple alternative well-established transition metal-catalyzed processes.

Language: Английский

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Advances and Prospects in Understanding London Dispersion Interactions in Molecular Chemistry

Angewandte Chemie, Journal Year: 2023, Volume and Issue: 136(12)

Published: Dec. 5, 2023

Abstract London dispersion (LD) interactions are the main contribution of attractive part van der Waals potential. Even though LD effects driving force for molecular aggregation and recognition, role these omnipresent in structure reactivity had been largely underappreciated over decades. However, recent years considerable efforts have made to thoroughly study their potential as a chemical design element structures catalysis. This was possible through fruitful interplay theory experiment. review highlights results advances utilizing structural motif understand utilize intra‐ intermolecularly LD‐stabilized systems. Additionally, we focus on quantification fundamental reactions.

Language: Английский

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