Applications of low-valent compounds with heavy group-14 elements

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(12), P. 6150 - 6243

Published: Jan. 1, 2024

We have compiled the recent progress of low-valent group-14 compounds in catalysis, polymerization, small molecule activation, thin film deposition, photophysical properties, and medicinal properties.

Language: Английский

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Unveiling Three Interconvertible Redox States of Boraphenalene

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(9), P. 6145 - 6156

Published: Feb. 21, 2024

Neutral 1-boraphenalene displays the isoelectronic structure of phenalenyl carbocation and is expected to behave as an attractive organoboron multi-redox system. However, isolation new redox states have remained elusive even though preparation neutral boron(III)-containing phenalene compounds been extensively studied. Herein, we adopted N-heterocyclic carbene ligand stabilization approach achieve first stable ambipolar 1-boraphenalenyl radical 1•. The cation 1+ anion 1– also electrochemically observed chemically isolated, representing forms boraphenalene for study non-Kekulé polynuclear benzenoid molecules. Experimental theoretical investigations suggest that interconvertible three-redox-state species undergo reversible electronic modifications, which primarily take place on polycyclic framework molecules, exhibiting atypical behavior compared known donor-stabilized compounds. Initial reactivity studies, aromaticity evaluations, photophysical studies show redox-state-dependent trends. While luminescent in both solution solid states, 1• exhibits boron-centered undergoes substitution chemistry boraphenalenyl skeleton serves a single-electron transfer reductant.

Language: Английский

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The influential IPr: 25 years after its discovery

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

25 Years after the discovery of most influential NHC ligand, we revisit and highlight studies involving IPr that have shaped field NHC-transition metal catalysis.

Language: Английский

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Recent Advances in the Synthesis of Heterocyclics via Cascade Cyclization of Propargylic Alcohols

Advanced Synthesis & Catalysis, Journal Year: 2020, Volume and Issue: 363(4), P. 852 - 876

Published: Nov. 18, 2020

Abstract Heterocyclic compounds are important organic and have emerged as key scaffolds in numerous drugs, natural products, vitamins, biologically pharmaceutically active compounds. Over the past few decades, development of versatile methodologies employing propargylic alcohols synthons for construction heterocyclic skeletons has attracted great attention from synthetic chemists. In this review, recent developments cascade cyclization with diverse nucleophiles to construct summarized. According types nucleophiles, these reactions can be divided into four categories: 1) Reactions involving C‐nucleophiles capture allenyl carbocation; 2) O, S‐nucleophiles 3) N, P‐nucleophiles 4) halo‐nucleophiles carbocation. magnified image

Language: Английский

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Hierarchical Porous Organometallic Polymers Fabricated by Direct Knitting: Recyclable Single‐Site Catalysts with Enhanced Activity

Advanced Materials, Journal Year: 2019, Volume and Issue: 32(6)

Published: Dec. 6, 2019

Porous organometallic polymers (POMPs) with hierarchical pore structures, high specific surface areas, and atomically dispersed metal (Ir, Pd, Ru) centers are successfully fabricated by a facile one-pot method through direct knitting of diverse N-heterocyclic carbene (NHC-M) complexes. These can function as recyclable solid single-site catalysts exhibit excellent catalytic activity selectivity in both dehydrogenation hydrogenation reactions even at ppm-level catalyst loadings. Remarkably, record turnover number (TON) 1.01 × 106 is achieved the levulinic acid to γ-valerolactone, which 750 times higher than that attained corresponding bis-NHC-Ir complex.

Language: Английский

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Quantifying the Electronic and Steric Properties of 1,3-Imidazole-Based Mesoionic Carbenes (iMICs)

Organometallics, Journal Year: 2020, Volume and Issue: 39(10), P. 1719 - 1729

Published: March 9, 2020

1,3-Imidazole-based mesoionic carbenes (iMICs) are a very promising class of carbon-donor ligands in synthesis and catalysis. However, systematic study the quantification stereoelectronic properties iMICs is lacking. This most likely due to absence rational synthetic routes suitable iMIC compounds. Herein, we report appropriate phosphinidene (iMICAr)PPh (iMICAr = :CCH(NDipp)2CAr; Ar Ph (5a), DMP (5b); 4-Me2NC6H4; Dipp 2,6-iPr2C6H3), selenium (iMICAr)Se (Ar (6a), (6b)), nickel carbonyl compounds (iMICAr)Ni(CO)3 (7a), (7b)). The π-accepting property iMICAr (2a), (2b)) has been evaluated by 31P 77Se NMR spectroscopic analyses 5 6, respectively. overall donor 2 assessed determining Tolman electronic parameter (TEP) 7. Studies suggest that (2) stronger σ donors weaker π acceptors compared classical N-heterocyclic (NHCs). steric profile obtained calculating percentage buried volume (%Vbur) for (iMICAr)CuX Ph, X I (8a); DMP, Br (8b)).

Language: Английский

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Systematic Design of a Frustrated Lewis Pair Containing Methyleneborane and Carbene for Dinitrogen Activation

Inorganic Chemistry, Journal Year: 2021, Volume and Issue: 60(8), P. 5598 - 5606

Published: March 31, 2021

Activation of atmospherically abundant dinitrogen (N2) by metal-free species under mild reaction conditions has been one the most challenging areas in chemistry for decades. Very recent but limited progress N2 activation boron species, including two-coordinated borylene and methyleneborane three-coordinated borole borane, made toward activation. Here, we systematically probe an experimentally viable frustrated Lewis pair (FLP) containing two moieties (methyleneborane carbene) via density functional theory (DFT) calculations, which proven to be efficient approach a thermodynamically kinetically favorable manner. Aromaticity is found play crucial role stabilization product. This study could valuable alternative development chemistry, highlighting great potential FLP functionalization.

Language: Английский

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Recent advances in organic synthesis applying elemental selenium

Tetrahedron, Journal Year: 2022, Volume and Issue: 112, P. 132752 - 132752

Published: March 31, 2022

Language: Английский

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Recent advances of mesoionic N-heterocyclic olefins

Dalton Transactions, Journal Year: 2022, Volume and Issue: 51(24), P. 9191 - 9198

Published: Jan. 1, 2022

This Perspective article highlights the recent development of mesoionic N-heterocyclic olefins (mNHOs), where exo-cyclic olefinic carbon is not bonded to strongly electron-withdrawing groups. The unquenched basicity and nucleophilicity make mNHOs strong σ-donors enable unique reactivity patterns.

Language: Английский

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1,3‐Imidazole‐Based Mesoionic Carbenes and Anionic Dicarbenes: Pushing the Limit of Classical N‐Heterocyclic Carbenes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(36)

Published: May 3, 2023

Classical N-heterocyclic carbenes (NHCs) featuring the carbene center at C2-position of 1,3-imidazole framework (i.e. C2-carbenes) are well acknowledged as very versatile neutral ligands in molecular materials sciences. The efficiency and success NHCs diverse areas is essentially attributed to their persuasive stereoelectronics, particular potent σ-donor property. with unusual C4 (or C5) position, so-called abnormal (aNHCs) or mesoionic (iMICs), however superior σ-donors than C2-carbenes. Hence, iMICs have substantial potential sustainable synthesis catalysis. main obstacle this direction rather demanding synthetic accessibility iMICs. aim review article highlight recent advances, particularly by author's research group, accessing stable iMICs, quantifying properties, exploring applications In addition, viability use vicinal C4,C5-anionic dicarbenes (ADCs), also based on an framework, presented. As will be apparent following pages, ADCs hold potentials pushing limit classical enabling access conceptually new main-group heterocycles, radicals, catalysts, sets, more.

Language: Английский

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