Counterintuitive Chemistry: Carbene Stabilization of Zero-Oxidation State Main Group Species

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(10), P. 5592 - 5612

Published: March 6, 2023

Carbenes have evolved from transient laboratory curiosities to a robust, diverse, and surprisingly impactful ligand class. A variety of different carbenes significantly contributed the development low-oxidation state main group chemistry. This Perspective focuses upon advances in chemistry carbene complexes containing element cores formal oxidation zero, including their diverse synthetic strategies, unusual bonding structural motifs, utility transition metal coordination activation small molecules.

Language: Английский

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Recent advances in the chemistry of isolable carbene analogues with group 13–15 elements

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(8), P. 3896 - 3951

Published: Jan. 1, 2024

This review provides an overview of main group carbene analogues, covering recent advancements, synthesis strategies, and the diverse reactivity elements in groups 13–15 based on their structural characteristics.

Language: Английский

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Molecular bismuth(iii) monocations: structure, bonding, reactivity, and catalysis

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(37), P. 4483 - 4495

Published: Jan. 1, 2021

Structurally defined, molecular bismuth(iii) cations show remarkable properties in coordination chemistry, Lewis acidity, and redox allowing for unique applications synthetic chemistry.

Language: Английский

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Charge Makes a Difference: Molecular Ionic Bismuth Compounds

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(24)

Published: Feb. 27, 2023

Key challenges in modern synthetic chemistry include the design of reliable, selective, and more sustainable methods, as well development promising candidates for new materials. Molecular bismuth compounds offer valuable opportunities they show an intriguing spectrum properties that is yet to be fully exploited: a soft character, rich coordination chemistry, availability broad variety oxidation states (at least +V -I) formal charges +3 -3) at Bi atoms, reversible switching between multiple states. All this paired with status non-precious (semi-)metal good tendency towards low toxicity. Recent findings some these only come into reach, or can substantially optimized, when charged are specifically addressed. In review, essential contributions synthesis, analyses, utilization ionic highlighted.

Language: Английский

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Isolation of an Annulated 1,4‐Distibabenzene Diradicaloid

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(19)

Published: Jan. 4, 2023

The first 1,4-distibabenzene-1,4-diide compound [(ADC)Sb]2 (5) based on an anionic dicarbene (ADC) (ADC=PhC{N(Dipp)C}2 , Dipp=2,6-iPr2 C6 H3 ) is reported as a bordeaux-red solid. Compound 5, featuring central six-membered C4 Sb2 ring with formally SbI atoms may be regarded base-stabilized cyclic bis-stibinidene in which each of the Sb bears two lone-pairs electrons. 5 undergoes 2 e-oxidation Ph3 C[B(C6 F5 )4 ] to afford [B(C6 ]2 (6) brick-red Each 6 has unpaired electron and lone-pair. broken-symmetry open-shell singlet diradical solution for (6)2+ calculated 2.13 kcal mol-1 more stable than closed-shell singlet. character according SS-CASSCF (state-specific complete active space self-consistent field) UHF (unrestricted Hartree-Fock) methods amounts 36 % 39 %, respectively. Treatments (PhE)2 yield [(ADC)Sb(EPh)]2 (7-E) (E=S or Se). Reaction (cod)Mo(CO)4 affords Mo(CO)4 (8).

Language: Английский

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Ligand Exchange at Carbon: Synthetic Entry to Elusive Species and Versatile Reagents

JACS Au, Journal Year: 2024, Volume and Issue: 4(5), P. 1709 - 1722

Published: April 15, 2024

How different is carbon compared to other elements in the periodic table? Can compounds be regarded as coordination complexes with central element undergoing a facile exchange of its ligands? Although clearly plays special role among table, recent studies have drawn parallels between bonding situation and reactivity transition metal complexes. This Perspective summarizes reports about ylidic zwitterionic that were shown exhibit ambiguous situations can interpreted donor–acceptor interactions similar bond neutral ligand. Based on this conception, ligand reactions prototypical realized at atoms, enabling new synthetic strategies for synthesis reactive species building blocks. In particular, N2, CO, phosphine ligands led development mild method accessing reagents unusual properties, such vinylidene ketenes or stable ketenyl anions, open up diverse but still poorly explored follow-up chemistry.

Language: Английский

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Access to Bis-Silylene-Stabilized Group 13 Cations

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 6, 2025

Herein, we report the isolation of pyridine moiety-functionalized SiNSi pincer-based bis-silylene ligand (1) and its reactivity toward various halide precursors (X = Br I) group 13 elements (M Al, Ga, In). This gave us straightforward access to pincer-coordinated cations (2–7). These complexes are duly characterized by single-crystal X-ray diffraction studies, multinuclear magnetic resonance spectroscopy (1H, 13C, 29Si), high-resolution mass spectrometry techniques. Their electronic properties were further analyzed with help quantum chemical calculations.

Language: Английский

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Carbodicarbene Bismaalkene Cations: Unravelling the Complexities of Carbene versus Carbone in Heavy Pnictogen Chemistry

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(12), P. 6682 - 6690

Published: Dec. 9, 2020

We report a combined experimental and theoretical study on the first examples of carbodicarbene (CDC)-stabilized bismuth complexes, which feature low-coordinate cationic centers with C=Bi multiple-bond character. Monocations [(CDC)Bi(Ph)Cl][SbF6 ] (8) [(CDC)BiBr2 (THF)2 ][SbF6 (11), dications [(CDC)Bi(Ph)][SbF6 ]2 (9) [(CDC)BiBr(THF)3 ][NTf2 (12), trication [(CDC)2 Bi][NTf2 ]3 (13) have been synthesized via sequential halide abstractions from (CDC)Bi(Ph)Cl2 (7) (CDC)BiBr3 (10). Notably, exhibit C ⇉ Bi double dative bonds thus represent unprecedented bismaalkene cations. The synthesis these species highlights unique non-reductive route to C-Bi π-bonding CDC-[Bi] complexes (7-13) were compared related NHC-[Bi] (1, 3-6) show substantially different structural properties. Indeed, CDC ligand has remarkable influence overall stability resulting suggesting that is superior NHC in heavy pnictogen chemistry.

Language: Английский

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Air-Stable Thermoluminescent Carbodicarbene-Borafluorenium Ions

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(1), P. 590 - 598

Published: Jan. 4, 2022

Borenium ions, originally synthesized as fundamentally important laboratory curiosities, have attracted significant attention due to their applications in catalysis and frustrated Lewis pair chemistry. However, investigations of the materials properties these types compounds are exceptionally rare. Herein, we report synthesis, molecular structures, optical a new class air-stable borenium stabilized by strongly donating carbodicarbene (CDC) ligand (2, 3, 6). Notably, CDC-borafluorenium ions exhibit thermoluminescence solution, result twisted intramolecular charge transfer process. The temperature responsiveness, which is observable naked eye, assessed over 20 -60 °C range. Significantly, compound 2 emits white light at lower temperatures. In solid state, borocations increased quantum yields aggregation-induced emission. with two different counteranions (Br-, BPh4-) were investigated evaluate effect anion size on solution solid-state properties. addition, CDCs containing both symmetrical unsymmetrical N-heterocycles (bis(1-isopropyl-3-methylbenzimidazol-2-ylidene)methane bis(1,3-dimethyl-1,3-dihydro-2H-benzo[d]imidazol-2-ylidene)methane) tested understand implications free rotation about CDC carbon-carbon bonds. experimental work complemented comprehensive theoretical analysis excited-state dynamics.

Language: Английский

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

Inorganic Chemistry, Journal Year: 2022, Volume and Issue: 61(46), P. 18640 - 18652

Published: Nov. 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.

Language: Английский

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