Functionalised [Ge₉Ni] Clusters as Homogeneous Single‐Site Catalysts for Olefin Isomerisation Reactions

ChemCatChem, Journal Year: 2023, Volume and Issue: 16(2)

Published: Nov. 6, 2023

Abstract Single‐site catalysis is an increasingly vital strategy to optimise heterogeneous catalytic reactions. In ideal case, the nature and population of catalytically active sites are all identical, which impossible realise on a solid support. The idea single site catalysts transferred from homogeneous by incorporation transition metal with oxidation state 0 in surface small, soluble, molecular, homoatomic germanium atom cluster that also comprises main group atoms close zero. An optimised synthetic protocol for four compounds Hyp 3 Et[Ge 9 Ni]PR (R=Ph, p tolyl, i Pr, Me) presented, embedded Ge polyhedral cluster. products were characterised NMR spectroscopy, LIFDI/MS elemental analysis structurally R= Pr Me crystal X‐ray structure determination comprising closo ‐[Ge Ni] core. potential investigated various olefin isomerisation formation realized ligand dissociation, observed PPh . DFT calculations Me), Ni](tolyl) Ni](C 6 H 12 ) show exchange substrate molecules occurs during reaction. Since same principle, namely bare at surface, applies as single‐site since contrast classical abbreviation SSHoC S ingle ite Ho mogeneous C atalyst proposed this catalyst type. each active, enable considerable increase efficiency thus allow sustainable use expensive less abundant metals.

Language: Английский

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Ruthenium Decorated Tris-Silylated Germanium Zintl Clusters Featuring an Unexpected Ligand Arrangement

Molecules, Journal Year: 2025, Volume and Issue: 30(6), P. 1247 - 1247

Published: March 11, 2025

The incorporation of transition metal atoms into [Ge9] clusters is a widely studied area Zintl-cluster chemistry. Recently, it was shown that comprising single in the cluster surface show catalytic properties. Here, we present synthetic approach to four new compounds silylated Ge9 with organometallic ruthenium complexes. [η5-Ge9Hyp3]RuCp* (1), [η1-Ge9(SitBu2H)3]RuCp(PPh3)2 (2), and [Hyp3Ge9][RuCp(PPh3)2(MeCN)] (3b) (Cp = cyclopentadienyl, Cp* pentamethylcyclopentadienyl, Hyp Si(SiMe3)3, Ph C6H5, tBu tert-butyl) were characterized by means NMR spectroscopy single-crystal structure determination. In case 2, isomer an approximated C4v symmetric monocapped square antiprism nine Ge unexpected ligand arrangement three ditertbutylsilane ligands attached open obtained. [Hyp3Ge9][RuCp(PPh3)2] (3a) via LIFDI mass spectrometry. Overall, able steric demand Cp vs. hypersilylchloride strongly influence on cluster. addition, solvent also affects cluster, as appears atom 3a dissociates from upon acetonitrile coordination form 3b. These results choosing right tools makes big difference outcome metalation reaction.

Language: Английский

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Unconventional Parahydrogen-Induced Hyperpolarization Effects in Chemistry and Catalysis: From Photoreactions to Enzymes

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 6386 - 6409

Published: April 4, 2025

Nuclear spin hyperpolarization utilizing parahydrogen has the potential for broad applications in chemistry, catalysis, biochemistry, and medicine. This review examines recent chemical biochemical insights gained using parahydrogen-induced polarization (PHIP). We begin with photoinduced PHIP, which allows investigation of short-lived photoactivated catalysis. Next, we partially negative line effect, distinctive shape helps to reveal information about rapid exchange role catalytic species. The NMR signal enhancement a single proton oneH-PHIP is discussed, challenging underpinning concept necessity pairwise hydrogenation. Furthermore, examine metal-free PHIP facilitated by frustrated Lewis pair molecular tweezers radicaloids, demonstrating alternative routes Although symmetric molecules incorporating are silent, showcase methods that hyperpolarized states through post-hydrogenation reactions. discuss processes mediate transfer between target, expanding reach without synthesizing specialized precursors. conclude this highlighting uncovering H2 activation mechanisms hydrogenases. By providing detailed these diverse phenomena, aim familiarize reader versatility its mechanistic studies analysis.

Language: Английский

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A Zintl Cluster for Transition Metal-Free Catalysis: C═O Bond Reductions

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(46), P. 21213 - 21223

Published: Nov. 9, 2022

The first fully characterized boron-functionalized heptaphosphide Zintl cluster, [(BBN)P7]2- ([1]2-), is synthesized by dehydrocoupling [HP7]2-. Dehydrocoupling a previously unprecedented reaction pathway to functionalize clusters. [Na(18-c-6)]2[1] was employed as transition metal-free catalyst for the hydroboration of aldehydes and ketones. Moreover, greenhouse gas carbon dioxide (CO2) efficiently selectively reduced methoxyborane. This work represents examples catalysis where transformation cluster noninnocent.

Language: Английский

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Catalytic Alkyne Semihydrogenation with Polyhydride Ni/Ga Clusters

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(36)

Published: July 6, 2023

The bimetallic, decanuclear Ni3 Ga7 -cluster of the formula [Ni3 (GaTMP)3 (μ2 -GaTMP)3 (μ3 -GaTMP)] (1, TMP=2,2,6,6-tetramethylpiperidinyl) reacts reversibly with dihydrogen under formation a series (poly-)hydride clusters 2. Low-temperature 2D NMR experiments at -80 °C show that 2 consist mixture di- (2Di ), tetra- (2Tetra ) and hexahydride species (2Hexa ). structures 2Di 2Tetra are assessed by combination spectroscopy DFT calculations. cooperation both metals is essential for high hydrogen uptake cluster. Polyhydrides catalytically active in semihydrogenation 4-octyne to 4-octene good selectivity. example first its kind conceptually relates properties molecular, atom-precise transition metal/main group metal respective solid-state phase catalysis.

Language: Английский

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A robust Zintl cluster for the catalytic reduction of pyridines, imines and nitriles

Dalton Transactions, Journal Year: 2023, Volume and Issue: 52(38), P. 13787 - 13796

Published: Jan. 1, 2023

Despite p-block clusters being known for over a century, their application as catalysts to mediate organic transformations is underexplored. Here, the boron functionalized [P7] cluster [(BBN)P7]2- ([1]2-; BBN = 9-borabicyclo[3.3.1]nonane) applied in dearomatized reduction of pyridines, well hydroboration imines and nitriles. These afford amine products, which are important precursors pharmaceuticals, agrochemicals, polymers. Catalyst [1]2- has high stability these reductions: recycling nine times quinoline led virtually no loss catalyst performance. The can also be recycled between two different transformations, again with competency. mechanism pyridine was probed experimentally using variable time normalization analysis, computationally density functional theory. This work demonstrates that Zintl nitrogen containing substrates transition metal-free manner.

Language: Английский

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Insight into the formation of bismuth-tungsten carbonyl clusters

Communications Chemistry, Journal Year: 2023, Volume and Issue: 6(1)

Published: June 5, 2023

Multimetallic clusters play a key role as models to doped metals, candidates new types of superatomic catalysts and precursors multimetallic solids. Understanding formation pathways is an essential necessary step forward in the development cluster synthesis research, yet remains considerably lacking owing difficulty identification intermediates ill-defined nature common starting materials. Here we show progress this regard by investigating reactivity intermetallic solid nominal composition 'K5Ga2Bi4' with [W(cod)(CO)4] upon extraction ethane-1,2-diamine (en) 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane (crypt-222). Several polybismuthide by-products were identified along reaction pathway, ultimately forming salt [K(crypt-222)]3[µ:η3-Bi3{W(CO)3}2]∙en∙tol. DFT calculations revealed plausible schemes for transformations taking place mixture providing insight into complex on basis situ generation Bi22-.

Language: Английский

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Tuning the Inorganic Core of a reduced Ni₂Ge₂ Cluster

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(23)

Published: Feb. 13, 2024

Abstract Tetranuclear cores (M−E) 2 of transition metals (M) and tetrylenes (E II =Si, Ge, Sn) are key motifs in homogeneous heterogeneous catalysis. They exhibit a continuum M−M E−E bonding within the inorganic core that leads to variety structures for which there no specific synthetic methods. Herein, we report series highly reduced [Ni 0 Ge ] squares solely stabilized by bulky terphenyl (C 6 H 3 −2,6‐Ar ) ligands, provide complementary high‐yielding syntheses. Reactivity studies with common Lewis bases (carbene CO) evince structure can be transformed. We have investigated this modification computational means, offering rationale better understand across these clusters.

Language: Английский

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Zintl clusters as catalytic tools for synthesis

Trends in Chemistry, Journal Year: 2024, Volume and Issue: 6(7), P. 349 - 351

Published: April 29, 2024

Although known for over a century, only now are Zintl clusters being investigated as catalysts. These can serve intermediaries between discrete molecules and bulk solids, allowing them to act atom-precise models whose reactivity may map onto their heterogeneous counterparts. Key contributions in homogeneous catalysis discussed.

Language: Английский

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Mapping boron catalysis onto a phosphorus cluster platform

Dalton Transactions, Journal Year: 2022, Volume and Issue: 51(47), P. 18329 - 18336

Published: Jan. 1, 2022

Clusters of main group elements, such as phosphorus, arsenic, germanium, and tin - called Zintl clusters have been known for more than a century. However, their application in catalysis is largely unknown. Here, we tether boranes to seven-atom phosphorus cluster ({C8H14}BCH2CH2SiMe2)3P7 (2) demonstrate Lewis acid proof-of-principle that boron chemistry can be mapped onto using this method. Catalyst 2 was employed mediate key organic transformations, including the hydroboration carbodiimides, isocyanates, ketones, alkenes, alkynes, nitriles. To best our knowledge, first Zintl-based an innocent platform metal-free catalysis. By chaining boron, its treasure chest unlocked at these clusters. Hence, beyond method could find applications neutron capture therapy, stimuli responsive materials, cross-coupling, frustrated pair functional polymer chemistries.

Language: Английский

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