Combining geometric constraint and redox non-innocence within an ambiphilic PBiP pincer ligand

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

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Molecular-strain induced phosphinidene reactivity of a phosphanorcaradiene

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 29, 2024

Abstract Phosphanorcaradienes are an appealing class of phosphorus compounds that can serve as synthons transient phosphinidenes. However, the synthesis such species is a formidable task owing to their intrinsic high reactivity. Herein we report straightforward synthesis, characterization and reactivity studies phosphanorcaradiene, in which one benzene rings flanking fluorenyl substituents intramolecularly dearomatized through attachment atom. It facilely obtained by reduction phosphorus(III) dichloride precursor with potassium graphite. Despite being thermally robust, it acts synthetic equivalent phosphinidene. reacts trimethylphosphine isonitrile yield phosphanylidene-phosphorane 1-phospha-3-azaallene, respectively. When treated two molar equivalents azide, iminophosphane bis(imino)phosphane isolated, Moreover, capable activating ethylene alkyne afford [1 + 2] cycloaddition products, well oxidative cleavage Si–H N–H bonds secondary phosphines. All reactions proceed smoothly at room temperature without presence transition metals. The driving force for these most likely ring-constraint three-membered PC 2 ring recovery aromaticity ring.

Language: Английский

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Why Are Some Pnictogen(III) Pincer Complexes Planar and Others Pyramidal?

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(57)

Published: July 30, 2024

Geometrically-constrained pnictogen pincer complexes have emerged in recent years as platforms for unique stoichiometric and catalytic chemical transformations. These feature dynamic conformations ranging from fully planar at the centre to distorted-pyramidal geometries, well variation between phases. Although valued reactivity of is ascribed their there no unified model explain observed conformational outcomes across different ligands centres. Here we propose such a through computational analysis more than 1300 structures 64 (16 4 heavy pnictogens), explaining experimental observations making new predictions. By looking signatures bond stability (bond lengths, Wiberg indices) delocalization (NPA charges, Hirshfeld charges), our framework posits pnictogen-based σ-bonding effect that favours pyramidalization exists competition with ligand-based π-bonding planarity. Variations structure function identity, ligand tethering, electronics, aromaticity can be reconciled reference balance these two opposing forces. Careful consideration σ/π-bonding effects may aid rational design future predictable geometries reactivities.

Language: Английский

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A focus on phosphinophosphination of apolar bonds by a structurally constrained P–P bonded system

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

Published: Jan. 1, 2025

This article highlights recent work by Greb et al. on the phosphinophosphination of alkenes, alkynes, and carbonyls, with a focus how polarity P–P bond controls scope resulting reactivity.

Language: Английский

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Flash Communication: Ligand Centered Cooperative O–H Bond Splitting by a Mo(CO)₅(phosphine) Complex

Organometallics, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 22, 2025

The synthesis and reactivity of a molybdenum carbonyl complex ligated by geometrically constrained phosphorus trisamide are reported. Reaction with potassium tert-butoxide or methanol triggers ligand-centered substrate activation, leading to planarization the phosphine donor ligand. P–O bond formation, decarbonylation, insertion center into ligand P–N result in formation tetracarbonyl complexes rigid N,P-chelate ligands.

Language: Английский

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The Outstanding Ambiphilicity of Trialkylstibines among Trialkylpnictines: Power for Stepwise Deoxygenation and N–N Coupling of Nitroarenes

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

Published: March 12, 2025

The ongoing discovery of highly reactive ambiphilic main-group species has significantly advanced the development chemistry, particularly in realms small molecule activation and catalysis. Theoretically, compounds featuring smaller HOMO–LUMO gaps gain stronger ambiphilicity higher reactivity. In this work, we fundamentally demonstrate that Me3Sb holds smallest gap among trimethylpnictines, indicating its outstanding ambiphilicity. Correspondingly, superior reactivity toward deoxygenation electron-deficient nitroarenes been unambiguously revealed through control experiments. Furthermore, unprecedented SbIII/SbVO cycling between trialkylstibines their oxides established for catalytic transformation into azoxyarenes/azoarenes. This study opens a new chapter organoantimony derivatives fields redox

Language: Английский

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Meta-Xylene-Based Diamines with Protected Benzyl Sites: Potential NCN Pincer Ligands with Tunable Steric Profiles

Molecules, Journal Year: 2025, Volume and Issue: 30(6), P. 1331 - 1331

Published: March 16, 2025

Bulky NCN aryl-diamides featuring methyl groups in the benzyl positions were synthesized with aim of creating a new class meta-xylene-based trianionic pincer ligands where common decomposition pathway metal complexes via C-H activation is prevented. Sterically demanding substituents on furthermore provide steric protection centre and can help prevent dimerization complexes. While double deprotonation formation dilithium salt was straightforward, difficulties encountered when attempting to deprotonate ipso-CH proton central aryl ring yield ligands. This stands contrast related without benzylic positions. Experimental theoretical investigations led conclusion that challenges third are likely caused by an interplay increased electron density at nitrogen atoms hindrance. Both effects originate introduction positions, which make targeted less accessible. These results further insight into impact both electronic properties ligands, may find utility coordination chemistry applications metalation be achieved direct rather than requiring triple deprotonation.

Language: Английский

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

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

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Geometrically Constrained Bismuth Compounds

Structure and bonding, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Language: Английский

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Diverse Functionality of Molecular Germanium: Emerging Opportunities as Catalysts

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(35), P. 24209 - 24232

Published: Aug. 22, 2024

Fundamental research on germanium as the central element in compounds for bond activation chemistry and catalysis has achieved significant feats over last two decades. Designing strategies small molecule activations ultimate catalysts established capitalize orbital modalities of germanium, apparently imitating transition-metal frontier orbitals. There is a growing body examples contemporary implicating tunability orbitals through avant-garde approaches such geometric constrained empowered reactivity, bimetallic complementarity, cooperative etc. The goal this Perspective to provide readers with an overview emerging opportunities field germanium-based by perceiving underlying key principles. This will help convert discrete set findings into more systematic vision catalyst designs. Critical exposition germanium's participations evokes challenges involved innovative designs, wherein viewpoints are provided. We close addressing forward-looking directions catalytic manifold development. hope that be motivational applied constituent pragmatic catalysts.

Language: Английский

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