Contorting the Hetero Phosphaquinoid: Synthesis and Electronic Insights into a Non-planar, Ferrocenyl Phosphaquinoid

Dalton Transactions, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

We report the synthesis of an ambient-stable, ferrocene-embedded, anthraquinodimethane-based phosphaquinoid. The compound exhibits a pronounced butterfly-like distortion anthrylene core adopting highly contorted geometry in solid-state.

Language: Английский

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Reliable Diradical Characterization via Precise Singlet–Triplet Gap Calculations: Application to Thiele, Chichibabin, and Müller Analogous Diradicals

Journal of Chemical Theory and Computation, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 30, 2025

Accurately calculating the diradical character (y0) of molecular systems remains a significant challenge due to scarcity experimental data and inherent multireference nature electronic structure. In this study, various quantum mechanical approaches, including broken symmetry density functional theory (BS-DFT), spin-flip time-dependent (SF-TDDFT), mixed-reference (MRSF-TDDFT), complete active space self-consistent field (CASSCF), second-order perturbation (CASPT2), multiconfigurational pair-density (MCPDFT), are employed compute singlet–triplet energy gaps (EST) y0 values in Thiele, Chichibabin, Müller analogous diradicals. By systematically comparing results from these computational methods, we identify optimally tuned long-range corrected CAM-B3LYP BS-DFT framework as most efficient method for accurately affordably predicting both EST values. Additionally, our demonstrate that (i) MRSF-TDDFT performs much better than SF-TDDFT; (ii) MCPDFT is robust determining with minimal dependence on choice space. These findings provide insight into structure investigated molecules highlight effective strategies future studies domain. Thus, work not only advances understanding but also offers practical guidelines their investigation.

Language: Английский

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Dicationic Boron Derivatives of Schlenk’s and Thiele’s Hydrocarbon

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

Published: March 19, 2025

In recent years, neutral NHC-stabilized boryl radicals have been investigated as reactive species in various organic transformations. However, cationic boron significantly less explored. addition, boron-centered open-shell with S > 1/2 emerged attractive synthetic targets. this study, we provide a route to an radical cation salt of the weakly coordinating [Al(ORF)4]- (RF = C(CF3)3) anion. The procedure was extended dicationic diboron derivatives Schlenk's and Thiele's hydrocarbons meta- para-phenylene coupling units between spin centers. While most known isolable biradicals singlet ground-state thermally accessible triplet state, version hydrocarbon occupies spin-state, shown by combined electron paramagnetic resonance spectroscopy density functional theory studies. Furthermore, initial reactivity studies dications elemental sulfur diphenyldiselenide are presented.

Language: Английский

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Crystalline Boron‐Centered Analogues of Müller's Hydrocarbon

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: June 16, 2024

Comprehensive Summary Müller's hydrocarbon is a well‐known open‐shell singlet diradicaloid, yet its structural determination and redox property remain elusive due to extremely high reactivity. Herein, we report the successful synthesis full characterizations of first neutral boron‐centered analogue ( 4 ) hydrocarbon, along with dianionic 5 2− featuring three isolable states. In presence two equivalents N‐heterocyclic carbene (NHC), reduction 4,4”‐bis(triisopropylphenylbromoboryl)terphenyl 3 potassium graphite afforded NHC‐stabilized boryl diradicaloid near‐pure diradical character y 0 = 0.93). Stepwise reductions 4,4”‐bis(dimesitylboryl)terphenyl in THF yielded monoradical anion ·− dianion , respectively, accompanied by decreasing aromaticity within conjugated spacer. Experimental studies theoretical analyses revealed that both exhibit large spin distributions at boron atoms, ground states, small singlet‐triplet energy gaps.

Language: Английский

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Crystalline Radical Anion of a Diboratriazole and Its Conversion to a Neutral Radical Driven by a Carbene

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(30), P. 20945 - 20950

Published: July 21, 2024

One-electron reduction of diboratriazole

Language: Английский

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