Mononuclear palladium(I) and palladium(III) coordination compounds

Coordination Chemistry Reviews, Год журнала: 2025, Номер 535, С. 216605 - 216605

Опубликована: Март 17, 2025

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Radicalizing CO by Mononuclear Palladium(I)

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(19)

Опубликована: Март 18, 2024

Abstract A mononuclear, T‐shaped palladium(I) d 9 metalloradical ( 3 ), stabilized by a bulky carbazole‐based PNP‐ligand, was obtained reduction of palladium chloride or thermal Pd−C bond homolysis the corresponding neopentyl complex. Pressurizing with CO gave Pd(I) carbonyl complex, which structurally characterized X‐ray diffraction. Delocalization unpaired electron to carbon detected EPR spectroscopy and theoretically modeled DFT ab initio methods. The partially reduced radicalized slowly reacts di( tert ‐butyl) disulfide under homolytic S−S cleavage C−S formation give metallathioester.

Язык: Английский

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Stability and C–H Bond Activation Reactions of Palladium(I) and Platinum(I) Metalloradicals: Carbon-to-Metal H-Atom Transfer and an Organometallic Radical Rebound Mechanism

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(25), С. 14087 - 14100

Опубликована: Июнь 15, 2023

One-electron oxidation of palladium(0) and platinum(0) bis(phosphine) complexes enables isolation a homologous series linear d9 metalloradicals the form [M(PR3)2]+ (M = Pd, Pt; R tBu, Ad), which are stable in 1,2-difluorobenzene (DFB) solution for >1 day at room temperature when partnered with weakly coordinating [BArF4]- (ArF 3,5-(CF3)2C6H3) counterion. The exhibit reduced stability THF, decreasing order palladium(I) > platinum(I) PAd3 PtBu3, especially case [Pt(PtBu3)2]+, is converted into 1:1 mixture platinum(II) [Pt(PtBu2CMe2CH2)(PtBu3)]+ [Pt(PtBu3)2H]+ upon dissolution temperature. Cyclometalation [Pt(PtBu3)2]+ can also be induced by reaction 2,4,6-tri-tert-butylphenoxyl radical DFB, common rebound mechanism involving carbon-to-metal H-atom transfer formation an intermediate platinum(III) hydride complex, [Pt(PtBu2CMe2CH2)H(PtBu3)]+, has been substantiated computational analysis. Radical C-H bond oxidative addition correlated resulting MII-H dissociation energy Pt Pd), reactions 9,10-dihydroanthracene DFB provide experimental evidence proposed activation manifold platinum, although conversion derivatives considerably faster (t1/2 1.2 h) than [Pt(PAd3)2]+ ∼ 40 days).

Язык: Английский

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Dithiocarbamate-mediated thioamidation of arylglyoxylic acids by decarboxylative–decarbonylative C–C bond formation reactions

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(7), С. 1686 - 1693

Опубликована: Янв. 1, 2023

Dithiocarbamates are explored in decarboxylative–decarbonylative thioamidation of arylglyoxylic acids the presence Pd-catalyst. Cleavage two C–C bonds and one C–S bond occurs along with formation a new single strategy.

Язык: Английский

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An open-shell Ir(II)/Ir(IV) redox couple outperforms an Ir(I)/Ir(III) pair in olefin isomerization

Nature Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 20, 2025

Язык: Английский

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Synthesis and Characterization of Bimetallic Copper(I) Complexes Supported by a Hexadentate Naphthyridine-Based Macrocycle Ligand

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Апрель 22, 2025

Herein, we report the synthesis, characterization, and binding properties of a new ligand, N,N'-di-tert-butyl-3,7-diaza-1,5(2,7)-1,8-naphthyridinacyclooctaphane (tBuN6), with copper (I), CuI, centers. We demonstrate flexibility ability tBuN6 to adopt various conformations in solution when coordinated CuIcenters. NMR studies exhibit labile coordination nature CuI. However, lability complexes is blocked by counterion exchange, which enables use less coordinating solvents such as tetrahydrofuran (THF) avoids using acetonitrile. Thus, exchange [BF4]- tetrakis 3,5-bis(trifluoromethyl)phenyl borate, [B(ArF)4]-, 1·BF4, [Cu2(MeCN)2(tBuN6)][BF4], generates 1·B(ArF)4, stable THF reacts under CO atmosphere generate syn,syn bis(carbonyl) complex. This complex sufficiently Ar be characterized IR spectroscopy, latter revealing two stretching bands for bound CuI-centers at 2102 2088 cm-1.

Язык: Английский

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Reversible Single-Electron-Transfer to Oxygen in a Stable N-Heterocyclic Carbene Palladium(I) Metalloradical

Inorganic Chemistry, Год журнала: 2023, Номер 62(49), С. 19838 - 19842

Опубликована: Ноя. 22, 2023

The chemical and electrochemical one-electron oxidation of [Pd(IPr)2] (1) leads to the formation mononuclear palladium(I) complex [Pd(IPr)2][PF6] (2). This bench-stable metalloradical has been fully characterized its structure confirmed by X-ray diffraction analysis. EPR DFT studies confirm localization unpaired electron onto metal center. Low temperature NMR measurements reveal ability 2 reversibly coordinate reduce dioxygen molecule, leading a three-coordinate complex, [PdII(IPr)2(η1-O2)]+ (4), in which transferred superoxido ligand.

Язык: Английский

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Pd^II/Cu^I-Cocatalyzed Radical Arylation of gem-Difluoroalkenes Using Arylsulfonyl Chlorides

The Journal of Organic Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 8, 2024

A Pd

Язык: Английский

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Mononuclear Palladium(I) Aryl Complexes Performs Cross-Coupling Reactions with Organic Halides

Опубликована: Апрель 22, 2024

Mononuclear Pd(I) species represent the least understood Pd intermediates in Pd-catalyzed reactions and isolable complexes of type are exceedingly rare. Herein, we report synthesis characterization mononuclear bear-ing aryl ligands, namely [(IPr)Pd(ArTrip-R-p)] (ArTrip-R-p = 4-R-2,6-bis(2’,4’,6’-triisopropylphenyl)phenyl, R H, CF3), as well their with organic halides. The were prepared from [(IPr)PdCl2]2 corresponding lithium salts have been characterized by various spectroscopic methods. EPR spectroscopy calculation studies suggest nature. Reactivity using [(IPr)Pd(ArTrip-CF3-p)] representative revealed capability complex activating carbon-halogen bonds iodide benzyl In para-substituted bromides, C(aryl)-C(benzyl) cross-coupling products formed moderate to good yields. Kinetic studies, radical trapping experiments, theoretical calculations point out that likely sequential steps stepwise oxidative addition reaction bromide involving Pd(II) intermediate followed reductive elimination resulting Pd(III) intermediates.

Язык: Английский

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An Open-Shell IrII/IrIV Redox Couple Outperforms the Conventional IrI/IrIII Pair for the Catalytic Isomerization of Olefins

Опубликована: Май 9, 2024

The chemistry of mononuclear open-shell complexes precious transition metals is largely underdeveloped, which contrasts with that first-row and their catalytic applications. This particularly true for IrII its almost inexistent participation in catalysis. Here we report the synthesis characterization a small family metalloradicals constructed around POCOP pincer ligand (POCOP = C6H3-2,6-(OP(tBu)2)2) explore performance as catalysts olefin isomerization, fundamental process alkane metathesis. These paramagnetic species are up to 20 times more active than diamagnetic IrI analogues. Strikingly, elementary steps involved action both virtually identical according our computational investigations. However, proposed unprecedented IrII/IrIV redox cycle presents faster kinetics traditional IrI/IrIII route due much lower barriers key oxidative addition reductive elimination events, feature rationalize by means Activation Strain Model-Energy Decomposition Analysis-approach. In essence, first example system based on couple, contribution underexplored compounds stresses necessity broaden catalyst search design guidelines beyond conventional cycles, including those platinum-group metals.

Язык: Английский

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