Main Group Redox Catalysis of Organopnictogens: Vertical Periodic Trends and Emerging Opportunities in Group 15

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(4), С. 1699 - 1721

Опубликована: Янв. 19, 2021

A growing number of organopnictogen redox catalytic methods have emerged-especially within the past 10 years-that leverage plentiful reversible two-electron chemistry Group 15. The goal this Perspective is to provide readers context understand dramatic developments in catalysis over decade with an eye toward future development. An exposition fundamental differences atomic structure and bonding pnictogens, thus molecular electronic compounds, presented establish backdrop against which reactivity-and ultimately catalysis-is framed. deep appreciation these underlying periodic principles informs understanding differing modes evokes key challenges field moving forward. We close by addressing forward-looking directions likely animate area years come. What new manifolds can be developed through creative catalyst reaction design that take advantage intrinsic reactivity pnictogens drive discoveries catalysis?

Язык: Английский

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Bismuth Redox Catalysis: An Emerging Main-Group Platform for Organic Synthesis

ACS Catalysis, Год журнала: 2022, Номер 12(2), С. 1382 - 1393

Опубликована: Янв. 7, 2022

Bismuth has recently been shown to be able maneuver between different oxidation states, enabling access unique redox cycles that can harnessed in the context of organic synthesis. Indeed, various catalytic Bi platforms have discovered and revealed emerging opportunities field main group catalysis. The goal this perspective is provide an overview synthetic methodologies developed date, which capitalize on cycling. Recent methods via low-valent Bi(II)/Bi(III), Bi(I)/Bi(III), high-valent Bi(III)/Bi(V) couples are covered as well their underlying mechanisms key intermediates. In addition, we illustrate design strategies stabilizing bismuth species, highlight characteristic reactivity complexes, compared lighter p-block d-block elements. Although it not catalysis nature, also discuss a recent example non-Lewis acid, redox-neutral Bi(III) proceeding through organometallic steps. We close by discussing future directions hope Perspective will chemists with guiding principles for development transformations employing bismuth.

Язык: Английский

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Engineering Single‐Atom Nanozymes for Catalytic Biomedical Applications

Small, Год журнала: 2023, Номер 19(30)

Опубликована: Апрель 14, 2023

Abstract Nanomaterials with enzyme‐mimicking properties, coined as nanozymes, are a promising alternative to natural enzymes owing their remarkable advantages, such high stability, easy preparation, and favorable catalytic performance. Recently, the rapid development of nanotechnology characterization techniques, single atom nanozymes (SAzymes) atomically dispersed active sites, well‐defined electronic geometric structures, tunable coordination environment, maximum metal utilization developed exploited. With superior performance selectivity, SAzymes have made impressive progress in biomedical applications expected bridge gap between artificial enzymes. Herein, recent advances SAzyme preparation methods, mechanisms, systematically summarized. Their cancer therapy, oxidative stress cytoprotection, antibacterial biosensing discussed depth. Furthermore, appreciate these advances, main challenges, prospects for future also outlined highlighted this review.

Язык: Английский

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Metallomimetic Chemistry of a Cationic, Geometrically Constrained Phosphine in the Catalytic Hydrodefluorination and Amination of Ar–F Bonds

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(6), С. 3786 - 3794

Опубликована: Фев. 4, 2023

The synthesis, isolation, and reactivity of a cationic, geometrically constrained σ3-P compound in the hexaphenyl-carbodiphosphoranyl-based pincer-type ligand (1+) are reported. 1+ reacts with electron-poor fluoroarenes via an oxidative addition-type reaction C-F bond to PIII-center, yielding new fluorophosphorane-type species (PV). This was used catalytic hydrodefluorination Ar-F bonds PhSiH3, C-N bond-forming cross-coupling reactions between aminosilanes. Importantly, these closely mimics mode action transition metal-based catalysts.

Язык: Английский

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Cooperative Bond Activation and Catalytic CO₂ Functionalization with a Geometrically Constrained Bis(silylene)-Stabilized Borylene

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(12), С. 7011 - 7020

Опубликована: Март 20, 2023

Metal–ligand cooperativity has emerged as an important strategy to tune the reactivity of transition-metal complexes for catalysis and activation small molecules. Studies main-group compounds, however, are scarce. Here, we report synthesis, structural characterization, a geometrically constrained bis(silylene)-stabilized borylene. The one-pot reaction [(SiNSi)Li(OEt2)] (SiNSi = 4,5-bis(silylene)-2,7,9,9-tetramethyl-9H-acridin-10-ide) with 1 equiv [BBr3(SMe2)] in toluene at room temperature followed by reduction 2 potassium graphite (KC8) leads borylene [(SiNSi)B] (1), isolated blue crystals 45% yield. X-ray crystallography shows that (1) tricoordinate boron center distorted T-shaped geometry. Computational studies reveal HOMO represents lone pair orbital on is delocalized over Si–B–Si unit, while geometric perturbation significantly increases its energy. Borylene single electron transfer toward tris(pentafluorophenyl)borane (B(C6F5)3), forming frustrated radical [(SiNSi)B]•+[B(C6F5)3]•–, which can be trapped PhSSPh, affording ion [(SiNSi)BSPh][PhSB(C6F5)3] (3). Remarkably, cooperation between silylene allows facile cleavage N–H bond aniline, P–P white phosphorus, C═O ketones carbon dioxide, thus representing new type element-ligand In addition, strikingly effective catalyst dioxide reduction. plays key role catalytic chemical process.

Язык: Английский

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Ligand-enforced geometric constraints and associated reactivity in p-block compounds

Chemical Society Reviews, Год журнала: 2023, Номер 53(2), С. 764 - 792

Опубликована: Дек. 15, 2023

This review presents a group-wise summary of ligand enforced non-VSEPR geometries in compounds the p-block elements and discusses emergent consequences for reactivity.

Язык: Английский

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Metallomimetic C–F Activation Catalysis by Simple Phosphines

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(3), С. 2005 - 2014

Опубликована: Янв. 11, 2024

Delivering metallomimetic reactivity from simple p-block compounds is highly desirable in the search to replace expensive, scarce precious metals by cheap and abundant elements catalysis. This contribution demonstrates that catalysis, involving facile redox cycling between P(III) P(V) oxidation states, possible using only simple, cheap, readily available trialkylphosphines without need enforce unusual geometries at phosphorus or use external oxidizing/reducing agents. Hydrodefluorination aminodefluorination of a range fluoroarenes was realized with good very yields under mild conditions. Experimental computational mechanistic studies show phosphines undergo oxidative addition fluoroaromatic substrate via Meisenheimer-like transition state form fluorophosphorane. undergoes pseudotransmetalation step silane, initial fluoride transfer P Si, give experimentally observed phosphonium ions. Hydride hydridosilicate counterion then leads hydridophosphorane, which reductive elimination product reform phosphine catalyst. behavior analogous many classical transition-metal-catalyzed reactions so rare example both functional mechanistically catalysis main-group element system. Crucially, reagents used are commercially, easy handle, making these realistic prospect wide academic industrial settings.

Язык: Английский

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Free reactive oxygen species-independent dual enzymatic activity of iron single-atom catalyst for hydrogel-assisted portable visual analysis

Journal of Colloid and Interface Science, Год журнала: 2025, Номер 686, С. 420 - 429

Опубликована: Янв. 31, 2025

Язык: Английский

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Cooperative Heterobimetallic CO₂ Activation Involving a Mononuclear Aluminum(II) Intermediate

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Апрель 3, 2025

Molecular chemistry of aluminum most commonly involves AlIII ions due to their noble gas electronic configurations. In contrast, the AlII is underexplored and may contain undiscovered reaction manifolds. Here, we report CO2 activation a transient intermediate supported by chelating, dianionic ligand investigate structure details mechanisms required access this reactivity. We found that heterobinuclear complex, (NON)Al-FeCp(CO)2 (1), undergoes Al-Fe bond homolysis at ambient conditions reveal [(NON)Al]•/[CpFe(CO)2]• radical pair in situ. The presence predominantly Al-centered spin density (i.e., an ion) within was established quantum-chemical calculations with experiments which scavengers (TEMPO, benzophenone) induce homolysis. Exposure 1 atmosphere resulted insertion into bond. This net 2-electron reduction process computationally modeled using functional theory direct dynamics simulations, revealing two 1-electron steps and, thus, depends on stabilization high-energy [CO2]•- coordination aluminum. mechanism for unexpected given canonical predisposition multielectron processes demonstrates possibility discovering new profiles earth-abundant elements unusual oxidation states.

Язык: Английский

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Lewis Superacidic Heavy Pnictaalkene Cations: Comparative Assessment of Carbodicarbene-Stibenium and Carbodicarbene-Bismuthenium Ions

Inorganic Chemistry, Год журнала: 2022, Номер 61(46), С. 18640 - 18652

Опубликована: Ноя. 9, 2022

We report a comprehensive assessment of Lewis acidity for series carbone-stibenium and -bismuthenium ions using the Gutmann-Beckett (GB) method. These new antimony bismuth cations have been synthesized by halide abstractions from (CDC)PnBr3 [(pyCDC)PnBr2][Br] (CDC = carbodicarbene; Pn Sb or Bi; py pyridyl). The reaction (CDC)SbBr3 (1) with one two equivalents AgNTf2 (NTf2 bis(trifluoromethanesulfonyl)imide) AgSbF6 gives stibaalkene mono- dications form [(CDC)SbBr3-n][A]n (2-4; n 1,2; A NTf2 SbF6). trication [(CDC)2Sb][NTf2]3 (5) was also isolated collectively these molecules fill gap among cationic pnictaalkenes. are compared to related CDC-bismaalkene complexes 6-9. With goal preparing highly acidic compounds, tridentate bis(pyridine)carbodicarbene (pyCDC) used as ligand access (10, 12) trications [(pyCDC)Pn][NTf2]3 (Pn (11), Bi (13)), forgoing need second CDC in synthesis 5. bonding situation is elucidated through electron density energy decomposition analyses combination natural orbital chemical valence theory. In each complex, there exists CDC-Pn double interaction, consisting strong σ-bond weaker π-bond, whereby π-bond gradually strengthens increase charge complex. Notably, [(CDC)SbBr][NTf2]2 (4) has an acceptor number (AN) (84) that comparable quintessential acids such BF3, tricationic pnictaalkene 11 13 exhibit ANs 109 Sb) 84 Bi), respectively, which highest values reported any cation. Moreover, calculated fluoride ion affinities (FIAs) 99.8 94.3 kcal/mol, larger than SbF5 (85.1 kcal/mol), suggest superacids.

Язык: Английский

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