Reversible Oxidative Addition of Nonactivated C–H Bonds to Structurally Constrained Phosphenium Ions DOI
Daniel Roth, Alexander T. Radosevich, Lutz Greb

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(44), P. 24184 - 24190

Published: Oct. 25, 2023

A series of structurally constrained phosphenium ions based on pyridinylmethylamidophenolate scaffolds are shown to undergo P(III)/P(V) oxidative addition with C-H bonds alkynes, alkenes, and arenes. Nonactivated substrates such as benzene, toluene, deactivated chlorobenzene phosphorylated in quantitative yields. Computational spectroscopic studies suggest a low-barrier isomerization from bent T-shaped isomer that initiates phosphorus-ligand-cooperative pathway subsequent ring-chain tautomerism. Remarkably, bond activations occur reversibly, allowing for reductive elimination back P(III) at elevated temperatures or the exchange other substrates.

Language: Английский

Planar bismuth triamides: a tunable platform for main group Lewis acidity and polymerization catalysis DOI Creative Commons

Tyler J. Hannah,

W. Michael McCarvell,

Tamina Kirsch

et al.

Chemical Science, Journal Year: 2023, Volume and Issue: 14(17), P. 4549 - 4563

Published: Jan. 1, 2023

Geometric deformation in main group compounds can be used to elicit unique properties including strong Lewis acidity. Here we report on a family of planar bismuth(iii) complexes (cf. typically pyramidal structure for such compounds), which show geometric acidity that further tuned by varying the steric and electronic features triamide ligand employed. The structural dynamism bismuth was probed both solid solution phase, revealing at least three distinct modes intermolecular association. A modified Gutmann-Beckett method assess their electrophilicity employing trimethylphosphine sulfide addition triethylphosphine oxide as probes, providing insights into preference binding hard or soft substrates. Experimental studies were complemented computational assessment affinities dissection latter intrinsic bond strength energy components. results comparable triarylboranes, with added ability bind two bases simultaneously, reduced discrimination against We also study catalytic efficacy these ring opening polymerization cyclic esters ε-caprolactone rac-lactide. polymers obtained excellent dispersity values high molecular weights low catalyst loadings used. retain performance under industrially relevant conditions, suggesting they may useful less toxic alternatives tin catalysts production medical grade materials. Collectively, establish not only novel neutral platform acidity, but potentially valuable one catalysis.

Language: Английский

Citations

19
Combining geometric constraint and redox non-innocence within an ambiphilic PBiP pincer ligand DOI Creative Commons
Peter Coburger, Ana Guilherme Buzanich, Franziska Emmerling

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(16), P. 6036 - 6043

Published: Jan. 1, 2024

The first pincer ligand featuring a strictly T-shaped pnictogen donor moiety was synthesised. PBiP ligand's redox activity facilitates unprecedented ambiphilic bonding of the Bi centre with transition metals through Bi(6p) orbital.

Language: Английский

Citations

8
Hydrogen splitting at a single phosphorus centre and its use for hydrogenation DOI
Deependra Bawari, Donia Toami, Kuldeep Jaiswal

et al.

Nature Chemistry, Journal Year: 2024, Volume and Issue: 16(8), P. 1261 - 1266

Published: June 27, 2024

Language: Английский

Citations

8
Exploring Singlet Carbyne Anions and Related Low-Valent Carbon Species Utilizing a Cyclic Phosphino Substituent DOI
Chaopeng Hu, Xin‐Feng Wang, Chenyang Hu

et al.

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

Published: Jan. 22, 2025

ConspectusThe advancement of synthetic methodologies is fundamentally driven by a deeper understanding the structure–reactivity relationships reactive key intermediates. Carbyne anions are compounds featuring monovalent anionic carbon possessing four nonbonding valence electrons, which were historically confined to theoretical constructs or observed solely within environment gas-phase studies. These species possess potential for applications across diverse domains chemistry and ancillary fields. This Account details our focused efforts isolate singlet carbyne explores isolation range related low-valent species. Our achievements include synthesis characterization, under normal laboratory conditions, gold-substituted free carbenes, copper anion complexes, ketenyl anions, keteniminyl stannyne. have been accomplished using bulky cyclic phosphino substituent, effectively stabilizes these species.Our journey commenced with phosphinocarbenes, characterized robust carbon–gold covalent single bond, progressed complexes carbon–copper ionic bond. was realized through synergistic combination group closed-shell electron-rich late transition metal. The robustness bond contrasts markedly susceptibility imparts behavior characteristic phosphinocarbyne coordination sphere copper, thereby enabling unique transfer reactions. tri-active ambiphilic nature in enables formation three chemical bonds at center one-pot Subsequent investigations unveiled ligand exchange reactions site, leading generation stable crystalline anions. emerge as potent synthons capable producing array derivatives. In addition, we isolated phosphinostannyne, rare carbon–tin multiple two adjacent centers. Collectively, demonstrated remarkable propensity engaging spectrum reactions, underscoring their versatility confirming utility synthesizing uncharted, main species.The insights derived from research contribute broader may provide platform future innovations chemistry, catalytic processes, novel materials. As continue explore develop this area study, hope that might follow footsteps potentially finding various fields future.

Language: Английский

Citations

1
Free reactive oxygen species-independent dual enzymatic activity of iron single-atom catalyst for hydrogel-assisted portable visual analysis DOI

Fangning Liu,

Fangwen Jiao,

Tingting Wang

et al.

Journal of Colloid and Interface Science, Journal Year: 2025, Volume and Issue: 686, P. 420 - 429

Published: Jan. 31, 2025

Language: Английский

Citations

1
Cooperative Heterobimetallic CO2 Activation Involving a Mononuclear Aluminum(II) Intermediate DOI
Roushan Prakash Singh, Kevin P. Quirion, Joshua Telser

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 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.

Language: Английский

Citations

1
Planar Tetracoordinated Silicon (ptSi): Room-Temperature Stable Compounds Containing Anti-van’t Hoff/Le Bel Silicon DOI
Priyabrata Ghana, Jens Rump, Gregor Schnakenburg

et al.

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 143(1), P. 420 - 432

Published: Dec. 21, 2020

While a variety of compounds containing planar tetracoordinated carbon (ptC), the so-called anti-van't Hoff/Le Bel carbon, are known experimentally, stable systems silicon (ptSi) barely known. As part our studies on application stereoelectronically well-defined transition-metal fragments to stabilize in unprecedented bonding modes, we report herein synthesis and full characterization series thermally complexes general formula [Tp′(CO)2MSiC(R1)C(R2)M(CO)2Tp′] (M = Mo, W; R1 R2 Me or H, SiMe3, Ph; Tp′ κ3-N,N′,N″-hydridotris(3,5-dimethylpyrazolyl)borate), which incorporate ptSi atom addition two ptC atoms. The were obtained by reacting metallasilylidyne [Tp′(CO)2M≡Si–M(CO)2(PMe3)Tp′] with alkynes R1C≡CR2 comprehensively analyzed experimental quantum chemical calculations. analyses revealed that is embedded tricyclic trapezoidal core featuring one internal SiC2 outer M–Si–C three-membered rings, fused via Si–C bonds. structural peculiarities evoked presence an center, such as short M–Si bonds, nearly linear M–Si–M spine, long M–C atoms elucidated detailed analysis electronic structure, suggesting factor for stabilization geometry aromaticity central ring having delocalized π electrons. Remarkably, results further indicate existence both centers next each other isolated complexes.

Language: Английский

Citations

46
Thermoneutral N−H Bond Activation of Ammonia by a Geometrically Constrained Phosphine DOI
Josh Abbenseth, Oliver P. E. Townrow, José M. Goicoechea

et al.

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(44), P. 23625 - 23629

Published: Sept. 3, 2021

A geometrically constrained phosphine bearing a tridentate NNS pincer ligand is reported. The effect of the geometric constraint on electronic structure was probed by theoretical calculations and derivatization reactions. Reactions with N-H bonds result in formation cooperative addition products. thermochemistry these transformations strongly dependent substrate, ammonia activation being thermoneutral. This represents first example molecular compound that reversibly activates via bond scission solution upon mild heating.

Language: Английский

Citations

38
Metal‐Free N−H Bond Activation by Phospha‐Wittig Reagents** DOI
Fabian Dankert,

Jan‐Erik Siewert,

Priyanka Gupta

et al.

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(32)

Published: May 20, 2022

N-containing molecules are mostly derived from ammonia (NH

Language: Английский

Citations

24
LNL-Carbazole Pincer Ligand: More than the Sum of Its Parts DOI Creative Commons
George Kleinhans, Aino J. Karhu, Hugo Boddaert

et al.

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(13), P. 8781 - 8858

Published: June 23, 2023

The utility of carbazole in photo-, electro-, and medicinal applications has ensured its widespread use also as the backbone tridentate pincer ligands. In this review, aim is to identify illustrate key features LNL-carbazolide binding transition metal centers (with L = flanking donor moieties, e.g., C, N, P, O-groups) a systematic bottom-up progression marked benefits attainable from (i) rigid aromatic scaffold (modulable both 1,8- 3,6-positions), (ii) significant electronic effect central carbazole-amido metal, tunable sterics electronics (iii) L-moieties (iv) wingtip R-groups on L-donors, with their corresponding influence coordination geometry, d-electron configuration, resultant reactivity. Systematic implementation ligand design strategies not isolation, but combinatorial approach, showcased demonstrate potential for functional molecules that are only modulable adaptable wide-ranging (e.g., stereoselective (photo)catalysis, challenging small molecule activation, SET redox applications, even chemotherapeutics) an indication future research efforts anticipated stem versatile assembly, metals s-, p-, f-block elements.

Language: Английский

Citations

15