An intriguing tetranuclear Rh-based polyoxometalate for the reduction of nitroarene and oxidation of aniline

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(71), P. 9902 - 9905

Published: Jan. 1, 2022

An organic-inorganic hybrid polyoxometalate Na5H5.68 [Na0.17Rh0.83III(C6H8N2)2Cl2]2(C8H8N2)2[As4W40O140Rh4IV(C6H4N2S)2]·nH2O (1) containing 5.66 Rh atoms is prepared; to our knowledge, it owns the largest number of in Rh-POM family. Compound 1 demonstrates good catalytic performance reduction nitrobenzene aniline and oxidation azobenzene under mild conditions. Moreover, catalyst exhibits high activity, excellent stability recyclability.

Language: Английский

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Controllable redox reaction cycle enabled by multifunctional Ru-containing polyoxometalate-based catalysts

Journal of Materials Chemistry A, Journal Year: 2023, Volume and Issue: 11(20), P. 10813 - 10822

Published: Jan. 1, 2023

Multifunctional Ru-POM catalysts implement path loops for the first time with a high TON of 485, 490, 3520 and 1980 selective oxidation AN to AOB, AB, NSB NB, 2000 photocatalytic reduction NB AN, respectively.

Language: Английский

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Construction of Hexameric Ru-Substitution POMs to Improve Photocatalytic H₂ Evolution

Inorganic Chemistry, Journal Year: 2023, Volume and Issue: 62(44), P. 18079 - 18086

Published: Oct. 25, 2023

Converting solar energy into storable hydrogen by employing green photocatalytic technology offers a reliable alternative for meeting the crisis. The polyoxometalates are promising candidate production photocatalysts because of their unique electronic and structural properties controllable design at molecular level. Introducing noble metals was proven to be an effective method greatly enhance efficiency polyoxometalates. Herein, two unprecedented compounds hexameric Ru-POMs, Na4H10[As2RuIV2W11O18(OH)4(H2O)6{AsW8RuIVO31(OH)Cl}2(B-β-AsW9O33)4]·93H2O (1) Na2H19[AsRuIII2W11O20(OH)2(H2O)6(RuIIICl3)(B-β-AsW9O33)6]·90H2O (2), were successfully self-assembled. H2 evolution rates 1 2 under optimal conditions 3578.75 3027.69 μmol h-1 g-1 with TONs 255 205, respectively. stability demonstrated series characterizations. Besides, possible mechanism proposed.

Language: Английский

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Enhanced Oxidative Coupling of Thiols to Disulfides Using the Visible-Light-Responsive POM@MOF Constructed with Ru Metalloligands

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: March 27, 2025

The photocatalytic oxidative coupling of thiols to disulfides by using visible light represents an economically viable and environmentally sustainable strategy. A novel POM@MOF photocatalyst (Ru–CdS–SiW) was synthesized through the encapsulation Keggin-type [SiW12O40]4– within a MOF composed Ru metalloligands {Cd4S2O16} clusters. In this structure, incorporation POMs MOFs reduced charge transport distance, facilitated separation transfer photogenerated charges holes, prevented recombination electron–hole pairs. Ru–CdS–SiW catalyst demonstrated exceptional catalytic performance, achieving 98.1% yield in S–S bond formation from 4-methylthiophenol with apparent quantum 4.8% at 440 nm. Through comprehensive exploratory experiments electron paramagnetic resonance (EPR) measurements, we elucidated mechanism underlying photoinduced thiols. Notably, reaction operates under mild visible-light conditions exhibits remarkable recyclability, presenting significant potential for applications sensitive systems, such as protein disulfide formation.

Language: Английский

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{Ti₆}/{Ti₁₀} Wheel Cluster Substituted Silicotungstate Aggregates

Inorganic Chemistry, Journal Year: 2021, Volume and Issue: 60(21), P. 16852 - 16859

Published: Oct. 21, 2021

Two novel Ti-oxo wheel cluster substituted silicotungstates (STs) [H2N(CH3)2]9H9[Ti6O6(SiW10O37)3]·11H2O (1) and [H2N(CH3)2]16H10[Ti10O11(SiW10O37)2(SiW9O35)2]·14H2O (2) have been made by hydrothermal reactions. The polyoxoanion of 1 is a ring-shaped trimer where Ti6O6 ({Ti6}) encapsulated three divacant [SiW10O37]10- (SiW10O37) fragments. However, 2 built two SiW10O37 units rare trivacant [SiW9O35]12- (SiW9O35) fragments further installs an unprecedented Ti10O11 ({Ti10}) double-wheel cluster. To the best our knowledge, in POM chemistry. Studies on catalytic oxidation properties reveal that exhibits high activity toward various sulfides using H2O2 as oxidant. Furthermore, can be facilely recycled reused for at least five cycles without obvious loss activity.

Language: Английский

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Controlled Assembly of Ru-Containing Polyoxometalates for Photocatalytic Activity of the Primary Amine Coupling Reaction

Inorganic Chemistry, Journal Year: 2022, Volume and Issue: 61(26), P. 9935 - 9945

Published: June 16, 2022

Three Ru-induced structural interconversion polyoxometalates (POMs), Na13H5[Ru4(H2O)2(Cl)2(WO2)4(AsW9O33)4]·43H2O (1), K5Na9H8[Ru2(WO2)4(AsW9O33)4]·50H2O (2), and KNa13H14[(WO2)4(AsW9O33)4]·34H2O (3), were successfully synthesized thoroughly characterized. Interconversion of structures was accomplished by changing the number active sites for compounds 1-3. All three contain one {As4W40O140} unit, showing similar characteristics except center (Ru). Interestingly, compound 1 [turnover (TON)= 486; turnover frequency (TOF)= 20 h-1] showed highly efficient photocatalysis in achieving oxidative coupling primary amines. Compound 2 (TON = 406, TOF 17 h-1) also found to promote with relatively poor efficiency; however, 3 178; 7.4 had no obvious contribution reaction system, a chain evidence indicates that catalytic performances are strongly dependent on element contents sites. Furthermore, Ru-containing POM-based photocatalysts conveniently recyclable reusable during photocatalytic processes. This study demonstrates possibility tuning efficiency stability well designing controlling their structures. The possible mechanism synthesis imine product is proposed based experimental studies.

Language: Английский

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Quinoline-polyoxometalate conglomerate as efficient heterogeneous catalysts for visible-light-mediated Minisci reactions

Journal of Organometallic Chemistry, Journal Year: 2023, Volume and Issue: 996, P. 122757 - 122757

Published: May 17, 2023

Language: Английский

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Synthesis, Structure, and Catalytic Activities of Two Multi-Rh-Decorated Polyoxometalates

Inorganic Chemistry, Journal Year: 2022, Volume and Issue: 61(39), P. 15310 - 15314

Published: Sept. 21, 2022

Two multi-Rh-incorporated polyoxometalates [NH2(CH3)2]10[Na4(H2O)8]H3[As4W42O142(OH)4(CH3COO)2Rh3(H2O)4]·13H2O·4[NH(CH3)2] (1) and [K4Na(H2O)6]KH10[As4W40O140Rh4(H2O)4]·34H2O (2) have been synthesized in acetate buffer solution. Polyanion 1a is built up atop of an acetate-modified rectangular framework [As4W42O142(OH)4(CH3COO)2]26-, while polyanion 2a contains a pure inorganic cryptand [As4W40O140]28-. All Rh atoms these two compounds share the same hexa-coordinate distorted-octahedral geometry are embedded into their cavities through As-Rh bonding with bond length around 2.304(4)-2.436(5) Å. Besides, they not only represent structural novelty but also demonstrate controllable proton conduction properties. Catalysts 1 2 can catalyze cycloaddition epoxides CO2 solvent-free system conjunction 1-ethyl-1-methylpyrrolidinium bromide.

Language: Английский

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Enhanced C(sp³)–H Selective Oxidation Using Efficient Polyoxometalate-Based Metal–Organic Framework Photocatalysts Synergized with Ir Metalloligands and Polyoxometalates

Chemistry of Materials, Journal Year: 2024, Volume and Issue: 36(22), P. 11150 - 11159

Published: Nov. 9, 2024

Achieving efficient selective visible light-induced oxidation of benzyl C(sp3)–H to more valuable double-bonded compounds holds significant promise for organic synthesis. In this work, we fabricated an example Ir metalloligand-modified POMOF crystalline material, CI-SiW, which is noteworthy as the first POM immobilized in a MOF via coordination bonding. Under excitation light (10 W, λ = 410 nm), CI-SiW can catalyze isochromane with turnover number and frequency 954 1740 h–1, respectively. Excitingly, displays best TOF compared previous photocatalysts under same conditions, realizing maximum yield minimum amount photocatalyst. Furthermore, had good cyclic structural stability, 90.4% was still obtained after three reaction cycles.

Language: Английский

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Ru Metalloligands Participate in the Construction of POM@MOF for Enhancing the Visible Photoinduced Baeyer–Villiger Oxidation Reaction

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(52), P. 24506 - 24516

Published: Dec. 17, 2024

Directed synthesis of high-efficiency visible photoinduced Baeyer–Villiger oxidation catalysts is primary significance. Here, the isopolymolybdate anion [β-Mo8O26]4– for first time encapsulated with photosensitive metalloligand [Ru(bpy)2(H2dcbpy)]2+ (bpy = 2,2′-bipyridine; H2dcbpy 2,2′-bipyridine-5,5′-dicarboxylic acid) to synthesize polyoxometalate@metal–organic frameworks, {(CdDMF)2[Ru(bpy)2(dcbpy)]3([β-Mo8O26])}·5DMF (Ru–Mo8). The composite photocatalyst Ru–Mo8 not only has a light absorption 700 nm but also shortens photogenerated electron transfer distances and accelerates charge proton transfer. can perform high selectivity up 96.7% yield under (λ > 400 nm) irradiation. turnover number frequency reaction were computed be 967 548 h–1, respectively, apparent quantum was 6.84% by 425 nm. Simultaneously, radical mechanism in O2/benzaldehyde system irradiation proposed.

Language: Английский

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