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  1. Artikel: Highly efficient multi-site synergistic catalysis of a polyoxovanadate-based metal–organic framework for benzylic C–H bond oxidation

    Dang, Tian-Yi / Li, Run-Han / Tian, Hong-Rui / Guan, Wei / Lu, Ying / Liu, Shu-Xia

    Journal of materials chemistry A. 2022 Aug. 10, v. 10, no. 31

    2022  

    Abstract: The selective oxidation of C–H bonds of benzylic compounds to synthesize high-value-added ketones remains a challenge under mild conditions, and the ambiguity of its oxidation mechanism limits the further development of this field. In this work, we ... ...

    Abstract The selective oxidation of C–H bonds of benzylic compounds to synthesize high-value-added ketones remains a challenge under mild conditions, and the ambiguity of its oxidation mechanism limits the further development of this field. In this work, we construct a polyoxometalate-based metal–organic framework (POMOF), [CuI2Cuᴵᴵ(bix)₂]{V₄O₁₂} (1, bix = 1,4-bis(imidazole-1-ylmethyl)benzene), successfully achieving the efficient oxidation catalysis of various benzylic compounds with outstanding conversion, selectivity and durability under mild conditions. Our experimental studies suggest that the highly catalytic activity of 1 derives from its attractive structure with multiple active sites, which consists of Vⱽ centers in a unique U-type {V₄O₁₂}⁴⁻ ({V₄}) cluster and Cuᴵ and Cuᴵᴵ centers bridged to the {V₄} cluster. Importantly, further theoretical calculations indicate that there exists synergistic catalysis between Cuᴵ/{V₄} sites and Cuᴵᴵ/{V₄} sites for 1 as catalyst in the oxidation of benzylic compounds, where the {V₄} cluster mainly provides deprotonation and oxidation sites, and the Cuᴵ site plays a role in the reduction of the oxidant, while the Cuᴵᴵ site plays a role in the adsorption of the oxidant. This is the first POMOF whose catalytic mechanism towards the oxidation of benzylic C–H bonds is deeply studied through the combination of experiments and theoretical calculations, providing a new perspective for the design of related catalysts.
    Schlagwörter adsorption ; catalysts ; catalytic activity ; coordination polymers ; deprotonation ; durability ; oxidants ; oxidation
    Sprache Englisch
    Erscheinungsverlauf 2022-0810
    Umfang p. 16514-16523.
    Erscheinungsort The Royal Society of Chemistry
    Dokumenttyp Artikel
    ZDB-ID 2702232-8
    ISSN 2050-7496 ; 2050-7488
    ISSN (online) 2050-7496
    ISSN 2050-7488
    DOI 10.1039/d2ta03886b
    Datenquelle NAL Katalog (AGRICOLA)

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  2. Artikel ; Online: Hollow Lindqvist-like-Shaped {V

    Tian, Hong-Rui / Zhang, Zhong / Dang, Tian-Yi / Liu, Shu-Mei / Lu, Ying / Liu, Shu-Xia

    Inorganic chemistry

    2021  Band 60, Heft 2, Seite(n) 840–845

    Abstract: A polyoxovanadate-based nickel-organic framework, [Ni(bib) ...

    Abstract A polyoxovanadate-based nickel-organic framework, [Ni(bib)
    Sprache Englisch
    Erscheinungsdatum 2021-01-06
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 1484438-2
    ISSN 1520-510X ; 0020-1669
    ISSN (online) 1520-510X
    ISSN 0020-1669
    DOI 10.1021/acs.inorgchem.0c02890
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: A novel polyoxovanadate-based Co-MOF: highly efficient and selective oxidation of a mustard gas simulant by two-site synergetic catalysis

    Tian, Hong-Rui / Zhang, Zhong / Liu, Shumei / Dang, Tian-Yi / Li, Xiao-Hui / Lü, Ying / Liu, Shu-Xia

    Journal of materials chemistry A. 2020 June 30, v. 8, no. 25 p.12398-12405

    2020  

    Abstract: Two novel polyoxovanadate-based metal–organic frameworks (MOFs), [Co(bib)]{V₂O₆} (V–Co-MOF) and [Ni(en)(bib)]{V₂O₆}·2H₂O (V–Ni-MOF) (bib = 1,4-bis(1H-imidazoly-1-yl)benzene, en = ethylenediamine) were facilely synthesized under mild hydrothermal ... ...

    Abstract Two novel polyoxovanadate-based metal–organic frameworks (MOFs), [Co(bib)]{V₂O₆} (V–Co-MOF) and [Ni(en)(bib)]{V₂O₆}·2H₂O (V–Ni-MOF) (bib = 1,4-bis(1H-imidazoly-1-yl)benzene, en = ethylenediamine) were facilely synthesized under mild hydrothermal conditions. Single-crystal X-ray diffraction analysis shows that the V sites in both compounds adopt {VO₄} tetrahedral coordination geometries, and the Co center in the V–Co-MOF presents a four-coordinated distorted tetrahedron configuration (coordinatively unsaturated metal sites, CUMS), while the Ni center in the V–Ni-MOF exhibits six-coordinated octahedral geometry (coordinatively saturated metal sites, CSMS). Given that the CUMS can generally be used as active sites for catalytic reactions, we explored the catalytic activities of these two compounds for the oxidation of a mustard gas simulant, 2-chloroethyl ethyl sulfide (CEES). The experimental results indicate that they can catalyze the oxidation of CEES to give the only nontoxic product, 2-chloroethyl ethyl sulfoxide (CEESO). Significantly, the V–Co-MOF exhibits higher catalytic activity; it converts 100% of CEES in 10 min, whereas V–Ni-MOF converts only 47.5% of CEES under identical conditions. Researching the mechanism of the catalytic reaction revealed that the excellent catalytic performance of the V–Co-MOF was attributed to the two-site synergetic effect: (1) the oxidant H₂O₂ interacts with the V site to produce peroxovanadium with higher oxidation activity; (2) the S atom in CEES coordinates with the four-coordinated Co(ii) center to obtain 2-chloroethyl ethyl sulfonium cation (CEES+), which makes the CEES more easily oxidize to CEESO based on the oxidation mechanism of peroxovanadium and shortens the molecular size distance between CEES and the obtained peroxovanadium, thereby greatly improving the rate of the catalytic reaction. To our knowledge, this is the first dual-active-site polyoxometalate-based MOF catalyst for catalysing the oxidative detoxification of CEES.
    Schlagwörter X-ray diffraction ; active sites ; aromatic compounds ; catalysts ; catalytic activity ; cations ; cobalt ; coordination polymers ; ethylenediamines ; geometry ; hydrogen peroxide ; molecular weight ; nickel ; organic sulfur compounds ; oxidants ; oxidation
    Sprache Englisch
    Erscheinungsverlauf 2020-0630
    Umfang p. 12398-12405.
    Erscheinungsort The Royal Society of Chemistry
    Dokumenttyp Artikel ; Online
    ZDB-ID 2702232-8
    ISSN 2050-7496 ; 2050-7488
    ISSN (online) 2050-7496
    ISSN 2050-7488
    DOI 10.1039/d0ta00537a
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  4. Artikel ; Online: A highly stable polyoxovanadate-based Cu(i)–MOF for the carboxylative cyclization of CO₂ with propargylic alcohols at room temperature

    Tian, Hong-Rui / Zhang, Zhong / Liu, Shumei / Dang, Tian-Yi / Li, Zhuo / Lü, Ying / Liu, Shu-Xia

    Green chemistry. 2020 Nov. 2, v. 22, no. 21 p.7513-7520

    2020  

    Abstract: A novel polyoxovanadate-based copper(i)–organic framework, [Cuᴵ(bib)]₄{Vⱽ₄O₁₂} (V–Cu–MOF, bib = 1,4-bis(1H-imidazoly-1-yl)benzene), is facilely synthesized under mild hydrothermal conditions. The structure of the V–Cu–MOF is constructed from a cyclic {V₄ ... ...

    Abstract A novel polyoxovanadate-based copper(i)–organic framework, [Cuᴵ(bib)]₄{Vⱽ₄O₁₂} (V–Cu–MOF, bib = 1,4-bis(1H-imidazoly-1-yl)benzene), is facilely synthesized under mild hydrothermal conditions. The structure of the V–Cu–MOF is constructed from a cyclic {V₄O₁₂}⁴⁻ polyanion cluster and a 1D chain Cu(i)–MOF ([Cuᴵ(bib)]⁺). The presence of the {V₄O₁₂}⁴⁻ cluster stabilizes the Cu(i)–MOF with Cu(i) as the center, thereby improving the stability of the V–Cu–MOF and enabling it to stably exist in various solvents and pH = 2–12 solutions. Additionally, the V–Cu–MOF as a heterogeneous catalyst can catalyze the carboxylative cyclization of CO₂ and propargylic alcohols to high value-added α-alkylidene cyclic carbonates at room temperature, and the conversion and selectivity are almost 100%. More importantly, no obvious decrease in the yield of the α-alkylidene cyclic carbonate is observed after ten cycles. These results indicate the excellent catalytic activity and sustainability of the V–Cu–MOF. Research on the mechanism of the catalytic reaction suggests that the high-density Cu(i) sites in the V–Cu–MOF are the catalytically active centers for activating the CC bonds of propargylic alcohols. To the best of our knowledge, this is the first example of polyoxometalate-based metal–organic framework catalyst for catalyzing the conversion of CO₂ to value-added α-alkylidene cyclic carbonates at room temperature.
    Schlagwörter ambient temperature ; anions ; carbon dioxide ; carbonates ; catalysts ; catalytic activity ; coordination polymers ; copper ; green chemistry ; pH ; value added
    Sprache Englisch
    Erscheinungsverlauf 2020-1102
    Umfang p. 7513-7520.
    Erscheinungsort The Royal Society of Chemistry
    Dokumenttyp Artikel ; Online
    Anmerkung NAL-AP-2-clean
    ZDB-ID 2006274-6
    ISSN 1463-9270 ; 1463-9262
    ISSN (online) 1463-9270
    ISSN 1463-9262
    DOI 10.1039/d0gc02812f
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  5. Artikel: One-pot mechanochemical synthesis to encapsulate functional guests into a metal–organic framework for proton conduction

    Wang, Yang / Lu, Ying / Li, Zhuo / Sun, Xiu-Wei / Zhang, Wan-Yu / Zhang, Shan / Wang, Jie / Dang, Tian-Yi / Zhang, Zhong / Liu, Shu-Xia

    Chemical communications. 2021 Sept. 6, v. 57, no. 71

    2021  

    Abstract: Through one-pot mechanochemical synthesis, a series of guests [imidazole, (aminomethyl)phosphonic acid, urea and sulfamic acid] are rapidly encapsulated into the pores of MOF NENU-3 while the MOF is formed. The synthesis of a MOF loaded with functional ... ...

    Abstract Through one-pot mechanochemical synthesis, a series of guests [imidazole, (aminomethyl)phosphonic acid, urea and sulfamic acid] are rapidly encapsulated into the pores of MOF NENU-3 while the MOF is formed. The synthesis of a MOF loaded with functional guests that used to take several days and require a multistep procedure can now be completed in one step within several minutes. The proton conductivities of the obtained composites increased by 2–3 orders of magnitude compared with NENU-3.
    Schlagwörter coordination polymers ; imidazole ; mechanochemistry ; phosphorous acid ; urea
    Sprache Englisch
    Erscheinungsverlauf 2021-0906
    Umfang p. 8933-8936.
    Erscheinungsort The Royal Society of Chemistry
    Dokumenttyp Artikel
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/d1cc03482k
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  6. Artikel: Purely inorganic frameworks based on polyoxometalate clusters with abundant phosphate groups: single-crystal to single-crystal structural transformation and remarkable proton conduction

    Zhang, Shan / Lu, Ying / Sun, Xiu-Wei / Li, Zhuo / Dang, Tian-Yi / Zhang, Zhong / Tian, Hong-Rui / Liu, Shu-Xia

    Chemical communications. 2020 Jan. 2, v. 56, no. 3

    2020  

    Abstract: A pure-inorganic framework based on {P₄Moⱽ₄Moⱽᴵ₂} clusters with rich phosphate groups has been synthesized. It underwent a single crystal to single crystal conversion in air to form a new framework with changes both in the metal valent state and ... ...

    Abstract A pure-inorganic framework based on {P₄Moⱽ₄Moⱽᴵ₂} clusters with rich phosphate groups has been synthesized. It underwent a single crystal to single crystal conversion in air to form a new framework with changes both in the metal valent state and coordination environment. The new framework exhibits an ultra-high proton conductivity of 1.33 × 10⁻² S cm⁻¹ at 95 °C and 98% relative humidity and excellent stability.
    Schlagwörter air ; chemical reactions ; phosphates ; relative humidity
    Sprache Englisch
    Erscheinungsverlauf 2020-0102
    Umfang p. 391-394.
    Erscheinungsort The Royal Society of Chemistry
    Dokumenttyp Artikel
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/c9cc08696j
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  7. Artikel ; Online: A multicentre synergistic polyoxometalate-based metal–organic framework for one-step selective oxidative cleavage of β-O-4 lignin model compounds

    Tian, Hong-Rui / Liu, Yi-Wei / Zhang, Zhong / Liu, Shumei / Dang, Tian-Yi / Li, Xiao-Hui / Sun, Xiu-Wei / Lü, Ying / Liu, Shu-Xia

    Green chemistry. 2020 Jan. 2, v. 22, no. 1 p.248-255

    2020  

    Abstract: A novel mixed-valence polyoxovanadate-based copper–organic framework, [Cuᴵ(bbi)]₂{[Cuᴵ(bbi)]₂VIV2Vⱽ₈O₂₆}·2H₂O (NENU-MV-5, bbi = 1,1′-(1,4-butanediyl)bis(imidazole)), was facilely synthesized from routine reagents under mild hydrothermal conditions. Using ...

    Abstract A novel mixed-valence polyoxovanadate-based copper–organic framework, [Cuᴵ(bbi)]₂{[Cuᴵ(bbi)]₂VIV2Vⱽ₈O₂₆}·2H₂O (NENU-MV-5, bbi = 1,1′-(1,4-butanediyl)bis(imidazole)), was facilely synthesized from routine reagents under mild hydrothermal conditions. Using NENU-MV-5 as a heterogeneous catalyst without any co-catalyst, one-step oxidative cleavage of β-O-4 lignin into phenols and aromatic acids with high catalytic activity and selectivity was realized under an oxygen atmosphere. No obvious decrease in activity was observed after five cycles, which indicates the excellent stability and sustainability of NENU-MV-5. The perfect catalytic performance of NENU-MV-5 can be attributed to the multi-site synergistic effect of the mixed-valence Vⱽ–O–Vᴵⱽ sites on polyoxovanadate for the oxidation of β-O-4 alcohol to β-O-4 ketone and the Cu(i) sites on the framework for the rapid cleavage of the Cα–Cᵦ bond of β-O-4 ketone. This system represented the first co-catalyst-free example for the one-step selective degradation of lignin catalyzed by a well-defined crystalline catalyst with definite composition and structure in a single solvent.
    Schlagwörter aromatic acids ; catalysts ; catalytic activity ; coordination polymers ; copper ; green chemistry ; imidazole ; lignin ; models ; oxidation ; oxygen ; phenols ; solvents ; synergism
    Sprache Englisch
    Erscheinungsverlauf 2020-0102
    Umfang p. 248-255.
    Erscheinungsort The Royal Society of Chemistry
    Dokumenttyp Artikel ; Online
    ZDB-ID 2006274-6
    ISSN 1463-9270 ; 1463-9262
    ISSN (online) 1463-9270
    ISSN 1463-9262
    DOI 10.1039/c9gc03626a
    Datenquelle NAL Katalog (AGRICOLA)

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  8. Artikel ; Online: One-pot mechanochemical synthesis to encapsulate functional guests into a metal-organic framework for proton conduction.

    Wang, Yang / Lu, Ying / Li, Zhuo / Sun, Xiu-Wei / Zhang, Wan-Yu / Zhang, Shan / Wang, Jie / Dang, Tian-Yi / Zhang, Zhong / Liu, Shu-Xia

    Chemical communications (Cambridge, England)

    2021  Band 57, Heft 71, Seite(n) 8933–8936

    Abstract: Through one-pot mechanochemical synthesis, a series of guests [imidazole, (aminomethyl)phosphonic acid, urea and sulfamic acid] are rapidly encapsulated into the pores of MOF NENU-3 while the MOF is formed. The synthesis of a MOF loaded with functional ... ...

    Abstract Through one-pot mechanochemical synthesis, a series of guests [imidazole, (aminomethyl)phosphonic acid, urea and sulfamic acid] are rapidly encapsulated into the pores of MOF NENU-3 while the MOF is formed. The synthesis of a MOF loaded with functional guests that used to take several days and require a multistep procedure can now be completed in one step within several minutes. The proton conductivities of the obtained composites increased by 2-3 orders of magnitude compared with NENU-3.
    Sprache Englisch
    Erscheinungsdatum 2021-09-06
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/d1cc03482k
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  9. Artikel ; Online: Purely inorganic frameworks based on polyoxometalate clusters with abundant phosphate groups: single-crystal to single-crystal structural transformation and remarkable proton conduction.

    Zhang, Shan / Lu, Ying / Sun, Xiu-Wei / Li, Zhuo / Dang, Tian-Yi / Zhang, Zhong / Tian, Hong-Rui / Liu, Shu-Xia

    Chemical communications (Cambridge, England)

    2019  Band 56, Heft 3, Seite(n) 391–394

    Abstract: A pure-inorganic framework based on {P4MoV4MoVI2} clusters with rich phosphate groups has been synthesized. It underwent a single crystal to single crystal conversion in air to form a new framework with changes both in the metal valent state and ... ...

    Abstract A pure-inorganic framework based on {P4MoV4MoVI2} clusters with rich phosphate groups has been synthesized. It underwent a single crystal to single crystal conversion in air to form a new framework with changes both in the metal valent state and coordination environment. The new framework exhibits an ultra-high proton conductivity of 1.33 × 10-2 S cm-1 at 95 °C and 98% relative humidity and excellent stability.
    Sprache Englisch
    Erscheinungsdatum 2019-12-09
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/c9cc08696j
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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