Insights into Single-Electron-Transfer Processes in Frustrated Lewis Pair Chemistry and Related Donor–Acceptor Systems in Main Group Chemistry

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(15), P. 9653 - 9675

Published: July 11, 2023

The activation and utilization of substrates mediated by Frustrated Lewis Pairs (FLPs) was initially believed to occur solely via a two-electron, cooperative mechanism. More recently, the occurrence single-electron transfer (SET) from base acid observed, indicating that mechanisms proceed one-electron-transfer processes are also feasible. As such, SET in FLP systems leads formation radical ion pairs, which have recently been more frequently observed. In this review, we aim discuss seminal findings regarding established insights into chemistry as well highlight examples process. addition, applications reported main group radicals will be reviewed discussed context understanding systems.

Language: Английский

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Site‐Selective Pyridine C−H Alkylation with Alcohols and Thiols via Single‐Electron Transfer of Frustrated Lewis Pairs

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(51)

Published: Oct. 31, 2022

A unified strategy for the deoxygenative or desulfurative pyridylation of various alcohols and thiols has been developed through a single-electron transfer (SET) process frustrated Lewis pairs (FLPs) derived from pyridinium salts PtBu3 . Mechanistic studies revealed that N-amidopyridinium serve as effective acids formation FLPs with , generated phosphine radical cation ionically couples in situ xanthate, eventually affording alkyl facile β-scission under photocatalyst-free conditions. The reaction efficiency was further accelerated by visible-light irradiation. This method is conceptually appealing using encounter complexes FLP chemistry to promote SET, which provides previously unrecognized opportunity selective heteroarylation diverse range functional groups, even complex settings mild

Language: Английский

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Design of Frustrated Lewis Pair Catalysts for Direct Hydrogenation of CO₂

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(46)

Published: Sept. 16, 2022

Despite recent progress in the chemistry of frustrated Lewis pairs (FLPs), direct FLP-catalyzed hydrogenation CO2 remains elusive. From a near-infinite array plausible pairs, it is challenging to identify individual combinations that are appropriate for catalyzing this reaction. To end, we propose mapping chemical composition FLPs their activity towards catalytic into formate. The maps, built upon linear scaling relationships, pinpoint specific FLP with proper complementary acidity and basicity optimally balance energetics cycle. One such combination was experimentally validated achieve hitherto unreported turnover transformation.

Language: Английский

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Dihydrogen Activation with a Neutral, Intermolecular Silicon(IV)‐Amine Frustrated Lewis Pair

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 28(60)

Published: July 21, 2022

The heterolytic cleavage of dihydrogen constitutes the hallmark reaction frustrated Lewis pairs (FLP). While being well-established for planar acids, such as boranes or silylium ions, observation primary H

Language: Английский

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Dinitrogen Activation: A Novel Approach with P/B Intermolecular FLP

The Journal of Physical Chemistry A, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 18, 2025

This study explores the reactivity of a new intermolecular P/B frustrated Lewis pair in context dinitrogen activation through push-pull mechanism. The ab initio molecular dynamics model known as atom-centered density matrix propagation plays pivotal role elucidating weakly associated encounter complex. In-depth analysis, mainly intrinsic reaction coordinate calculations, supports single-step Notably, N2 is observed to proceed concerted mechanism, proving slightly endergonic solvents like toluene and hexane. Furthermore, functional theory calculations reveal that becomes kinetically thermodynamically favorable when it subjected moderately oriented external electric field 2.57 V nm-1 along axis. In addition, natural bonding orbital extended transition state-natural orbitals for chemical valence analyses contribute more profound comprehension electron-transfer processes integral reaction.

Language: Английский

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Heterogeneous Frustrated Lewis Pair Catalysts: Rational Structure Design and Mechanistic Elucidation Based on Intrinsic Properties of Supports

Accounts of Chemical Research, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

ConspectusThe discovery of reversible hydrogenation using metal-free phosphoborate species in 2006 marked the official advent frustrated Lewis pair (FLP) chemistry. This breakthrough revolutionized homogeneous catalysis approaches and paved way for innovative catalytic strategies. The unique reactivity FLPs is attributed to base (LB) acid (LA) sites either spatial separation or equilibrium, which actively react with molecules. Since 2010, heterogeneous FLP catalysts have gained increasing attention their ability enhance performance through tailored surface designs improved recyclability, making them promising industrial applications. Over past 5 years, our group has focused on investigating strategically modifying various types solid that are from classic FLPs. We explored systematic characterization techniques unravel underlying mechanisms between active reactants. Additionally, we demonstrated critical role catalysts' intrinsic electronic geometric properties promoting formation stimulating synergistic effects. been greatly enhanced by use advanced such as synchrotron X-ray diffraction, neutron powder photoelectron spectroscopy, extended absorption fine structure, elemental mapping scanning transmission electron microscopy, paramagnetic resonance diffuse-reflectance infrared Fourier transform solid-state nuclear magnetic spectroscopy. These provided deeper insights into structural systems future design catalysts.Understanding distribution overlapping orbitals LA LB pairs essential inducing operando target reallocation external stimuli. For instance, silicoaluminophosphate-type zeolites weak orbital overlap, adsorption polar gas molecules leads heterolytic cleavage Alδ+–Oδ− bond, creating unquenched LA–LB pairs. In a Ru-doped metal–organic framework, Ru–N bond can be polarized metal–ligand charge transfer under light, forming Ru+–N– activation framework represents groundbreaking innovation expands potential existing materials. already employing chemistry dynamically generate products substrates, complete mechanistic interpretation requires thorough examination surrounding environment. hydrogen spillover surfaces improves conversion efficiency suppressing poisoning at metal sites. situ H2–H2O conditions enable production organic chemicals excellent activity selectivity new bifunctional via By highlighting novel featuring induction effects selection elucidate reaction mechanisms, hope this Account will offer strategies designing characterizing research community.

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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Dispersion Energy‐Stabilized Boron and Phosphorus Lewis Pairs

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(35)

Published: July 10, 2023

An isostructural series of boron/phosphorus Lewis pairs was systematically investigated. The association constants the were determined at variable temperatures, enabling extraction thermodynamic parameters. stabilization adduct increased with increasing size dispersion energy donor groups, although and acceptor properties remained largely unchanged. This data utilized to challenge state-of-the-art quantum chemical methods, which finally led an enhanced workflow for determination thermochemical weakly bound within accuracy 0.6 1.0 kcal mol-1 computed free energies.

Language: Английский

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Use of Microwave Dielectric Spectroscopy for the In Actu Assessment of Frustrated Lewis Pair Encounter Complexes

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(29), P. 19809 - 19817

Published: July 16, 2024

Frustrated Lewis pairs (FLPs) offer an important and promising paradigm for main group catalysis. Reported here is the use of microwave dielectric spectroscopy

Language: Английский

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Enhancement of London Dispersion in Frustrated Lewis Pairs: Towards a Crystalline Encounter Complex

Synlett, Journal Year: 2022, Volume and Issue: 34(10), P. 1122 - 1128

Published: Aug. 22, 2022

Abstract The encounter complex, i.e., the pre-organized assembly consisting of a Lewis acid and base, is fundamental concept in frustrated pair (FLP) chemistry. However, this donor–acceptor complex challenging to study due its transient nature. Here, we present combined theoretical experimental investigation on potential isolation an enabled by enhancement London dispersion forces between sterically encumbered base pair. Guided computational analyses, FLP originating from bulky triarylamine N(3,5-tBu2C6H3)3 novel triarylborane B(3,5-tBu2C6H3)3 was investigated, leading 1:1 co-crystal both components.

Language: Английский

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