Triplet State‐Promoted Kumada‐Corriu Coupling Catalyzed by Hydrotris(3,5‐diisopropylpyrazolyl)boratocobalt(III)diiodide DOI Creative Commons
Zekun Wang, Yann Cornaton, Jean‐Pierre Djukic

et al.

European Journal of Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 27(34)

Published: Sept. 4, 2024

Abstract The Kumada‐Corriu hetero‐coupling between an halogeno‐arene and arylmagnesiumbromide can be catalyzed with yields >80 % by the new hydrotris(3,5‐diisopropylpyrazolyl)boratocobalt(III)diiodide, i. e. Tp iPr CoI 2 . catalysis, which is significantly improved upon exposure to light as compared darkness, determined coexistence of low high spin states in a respective ratio ~3 : for crucial “Tp CoAr ” intermediate. pivotal cobalt(I) Co (I) ( thf ) n intermediate shown exclusively triplet state ground measured μ eff value 3.08 B at 293 K C 6 D DFT investigations confirm key role bisaryl‐cobalt(III) intermediates that they provide reaction pathway much lower activation barriers singlet state. low‐to‐high transition THF enhances reactivity intermediate, changes its coordination geometry from 18 electron OC ‐6 16 SPY ‐5 where ligand adopts nearly κ bonding mode. quantitative Independent Gradient Model analysis noncovalent interactions prefigure C−C covalent bond Co(Ar) informs peculiar importance crossover catalysis.

Language: Английский

Theoretical Mechanistic Study of C(sp3)−C(sp2) Cross‐Coupling by Photoredox‐Mediated Iridium(III)/Nickel(II)/Quinuclidine Triple Catalysis DOI
Shuang Wang, Run‐Han Li, Zhong‐Min Su

et al.

Chemistry - An Asian Journal, Journal Year: 2023, Volume and Issue: 18(11)

Published: April 15, 2023

The photoredox-mediated iridium(III)/nickel(II)/3-acetoxyquinuclidine triple-synergistic catalysis was comprehensively investigated by taking a C(sp3 )-C(sp2 ) bond cross-coupling as reaction model using density functional theory (DFT) calculations. synergistic mechanism of the triple catalytic system includes reductive quenching cycle (IrIII -*IrIII -IrII -IrIII ), an organocatalytic cycle, and nickel (NiII -NiI -NiIII -[NiIII ]⊖ -NiII ). Electronic process analysis shows that 3-acetoxyquinuclidine acts hydrogen atom transfer (HAT) catalyst to regioselectively provide α-carbon centered radical. Due more favorable oxidative addition C-Br Ni(I) than HAT avoid formation stable Ni(II) species, generated radical prefers be captured product Ni(III) form unusual [NiIII C⊕ species when employed. These theoretical insights not only deep electronic understanding iridium(III)/nickel(II) catalysis, but also clarify electron-withdrawing group effect quinuclidine, which has potential guiding role for further development new reactions.

Language: Английский

Citations

3
Indolyl Phosphine Nickel(II) Fluorido Complexes: Synthesis and Intermediates in Suzuki–Miyaura Cross‐Coupling Reactions DOI Creative Commons
Ouchan He, Beatrice Cula, Thomas Braun

et al.

Helvetica Chimica Acta, Journal Year: 2022, Volume and Issue: 106(2)

Published: Dec. 8, 2022

Abstract The C−F bond activation of pentafluoropyridine and 2,3,5,6‐tetrafluoropyridine at [Ni(cod) 2 ] (cod=1,5‐cyclooctadiene) in the presence phosphine PPh (Ind) (Ind=3‐methyl‐2‐indolyl) led to formation nickel(II) fluorido bis(phosphine) complexes trans ‐[Ni(F)(2‐C 5 NF 4 ){PPh (Ind)} HNF 3 ]. are characterized by intramolecular hydrogen bonds between NH group ligands ligand. Stochiometric model reactions with PhB(OH) revealed that former can be considered as intermediates Suzuki–Miyaura cross coupling reactions. Catalytic experiments were attempted using 10 mol‐% catalyst activities complex compared ones an analogous complex, bearing instead ligands. latter exhibited a somewhat lower catalytic activity suggesting slight influence H‐bonds outer coordination sphere.

Language: Английский

Citations

4
C–H and C–F bond activation of fluorinated propenes at Rh: enabling cross-coupling reactions with outer-sphere C–C coupling DOI Creative Commons
María Talavera, Soodeh Mollasalehi, Thomas Braun

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(22), P. 8472 - 8477

Published: Jan. 1, 2024

The reaction of [Rh{(E)-CF[double bond, length as m-dash]CHCF3}(PEt3)3] with Zn(CH3)2 results in the methylation alkenyl ligand to give [Rh{(E/Z)-C(CH3)[double m-dash]CHCF3}(PEt3)3]. Variable temperature NMR studies allowed identification a heterobinuclear rhodium-zinc complex an intermediate, for which structure [Rh(CH3)(ZnCH3){(Z)-C(CH3)[double m-dash]CHCF3}(PEt3)2] is proposed. Based on these stoichiometric reactions, unique Negishi-type catalytic cross-coupling reactions fluorinated propenes by consecutive C-H and C-F bond activation steps at room were developed. provide Rh deliver product, whereas C-C coupling occur via outer-sphere nucleophilic attack ligand.

Language: Английский

Citations

0
Rational Design to Activate Tetrafluoromethane by Two-Coordinate Borinium DOI
Shiqing Huang, Xiaoyu Yan

Inorganic Chemistry, Journal Year: 2023, Volume and Issue: 62(8), P. 3518 - 3524

Published: Feb. 16, 2023

The activation of tetrafluoromethane (CF4) is quite challenging. current methods have a high decomposition rate but are expensive, and therefore, their widespread use limited. Here, inspired by the successful C–F within saturated fluorocarbons, we designed rational approach based on two-coordinate borinium for activating CF4 using density functional theory (DFT) calculations. Our calculations predict that this both thermodynamically kinetically favorable.

Language: Английский

Citations

1
Triplet State‐Promoted Kumada‐Corriu Coupling Catalyzed by Hydrotris(3,5‐diisopropylpyrazolyl)boratocobalt(III)diiodide DOI Creative Commons
Zekun Wang, Yann Cornaton, Jean‐Pierre Djukic

et al.

European Journal of Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 27(34)

Published: Sept. 4, 2024

Abstract The Kumada‐Corriu hetero‐coupling between an halogeno‐arene and arylmagnesiumbromide can be catalyzed with yields >80 % by the new hydrotris(3,5‐diisopropylpyrazolyl)boratocobalt(III)diiodide, i. e. Tp iPr CoI 2 . catalysis, which is significantly improved upon exposure to light as compared darkness, determined coexistence of low high spin states in a respective ratio ~3 : for crucial “Tp CoAr ” intermediate. pivotal cobalt(I) Co (I) ( thf ) n intermediate shown exclusively triplet state ground measured μ eff value 3.08 B at 293 K C 6 D DFT investigations confirm key role bisaryl‐cobalt(III) intermediates that they provide reaction pathway much lower activation barriers singlet state. low‐to‐high transition THF enhances reactivity intermediate, changes its coordination geometry from 18 electron OC ‐6 16 SPY ‐5 where ligand adopts nearly κ bonding mode. quantitative Independent Gradient Model analysis noncovalent interactions prefigure C−C covalent bond Co(Ar) informs peculiar importance crossover catalysis.

Language: Английский

Citations

0