Jun Wang

Directly transforming carbohydrates into high value-added chemicals provides an economic and sustainable path for the utilization of the renewable biomass resource. Herein, we fabricated an efficient catalytic system for the straightforward conversion of various carbohydrates into 2,5-diformylfuran (DFF) by using vanadium oxide supported on high-silica mordenite (MOR) zeolites in the presence of hydrochloric acid. The synthesis of high-silica MOR zeolites was achieved in a template-free dense system featuring energy savings and environmental friendliness, delivering the SiO2/Al2O3 ratio up to 80. The conversion of fructose into DFF reached a high yield of 96.0% in a one-pot and one-step reaction by oxidation with atmospheric O2 (balloon), with facile recovery and good reusability of the catalyst. Good yields were also obtained in the direct synthesis of DFF from other carbohydrates including glucose, sucrose, inulin, raffinose, maltose, and starch. The high performance relied on the unique high-silica MOR skeleton, which (1) endowed the highly dispersed V species mainly in the form of isolated tetrahedrally coordinated [V2O8]6– species as the active oxidative sites and (2) provided satisfactory acidity for the formation of intermediate 5-hydroxymethylfurfural (HMF) and sufficient resistance to corrosion under an acid environment for good stability.Keywords: 2,5-Diformylfuran (DFF); 5-Hydroxymethylfurfural (HMF); Biomass conversion; Carbohydrates; Heterogeneous catalysis; Hydrothermal synthesis; Zeolite;

Synergistic Catalysis of Fe2O3 Nanoparticles on Mesoporous Poly(ionic liquid)-Derived Carbon for Benzene Hydroxylation with Dioxygen

Co-reporter:Qin Qin, Yangqing Liu, Wanjian Shan, Wei Hou, Kai Wang, Xingchen Ling, Yu Zhou, and Jun Wang

Industrial & Engineering Chemistry Research November 1, 2017 Volume 56(Issue 43) pp:12289-12289

Publication Date(Web):October 3, 2017

DOI:10.1021/acs.iecr.7b02566

Carbon-supported ferric oxide nanoparticles (Fe2O3 NPs) were constructed via directly carbonizing mesoporous poly(ionic liquid) with [Fe(CN)6]3– anions, which was prepared through the free-radical self-polymerization of ionic liquid monomer 1-allyl-3-vinylimidazolium chloride in a soft-template route and successive ion exchange with potassium ferricyanide. The unique mesoporous ionic networks enabled the molecular dispersion of ferric precursors and therefore resulted in highly dispersed Fe2O3 NPs on carbon. The catalyst exhibited high yield, remarkable turnover number, and good reusability in the reductant-free aerobic oxidation of benzene to phenol with O2. The synergistic effect of Fe2O3 NPs and carbon accounted for the high performance. This work delivered the first efficient and environmentally friendly heterogeneous catalyst for reductant-free benzene hydroxylation with O2.

Imidazolinium based porous hypercrosslinked ionic polymers for efficient CO2 capture and fixation with epoxides

Co-reporter:Jing Li;Degong Jia;Zengjing Guo;Yangqing Liu;Yinong Lyu;Yu Zhou

Green Chemistry (1999-Present) 2017 vol. 19(Issue 11) pp:2675-2686

Publication Date(Web):2017/06/06

DOI:10.1039/C7GC00105C

The efficient capture and chemical conversion of carbon dioxide (CO2) requires a solid simultaneously with a large surface area and highly effective active sites. Herein, imidazolinium based porous hypercrosslinked ionic polymers (HIPs) with a high surface area, rich micro/mesoporosity and abundant ionic sites were constructed via the hypercrosslinkage of 2-phenylimidazoline and benzyl halides, in which quaternization and Friedel–Crafts alkylation happened simultaneously to afford ionic polymeric networks. The obtained HIPs were efficient in the selective capture of CO2 and cycloaddition of CO2 with epoxides. High yield, stable reusability and good substrate compatibility were achieved under mild conditions (down to ambient conditions), dramatically outperforming the homogeneous ionic liquid monomer and post-modified analogues. The synergistic adsorption and conversion enabled the efficient low-temperature conversion of diluted CO2 (0.15 bar CO2 and 0.85 bar nitrogen, the simulation of flue gas) catalyzed by HIPs in the presence of co-catalyst ZnBr2. The in situ formed ionic sites with a high leaving ability being homogeneously embedded in the hypercrosslinked polymeric skeleton responded to the high adsorption and catalysis performance. This work highlights the functional HIPs as a versatile platform to reach efficient CO2 capture and conversion under mild conditions.

Direct aerobic oxidative homocoupling of benzene to biphenyl over functional porous organic polymer supported atomically dispersed palladium catalyst

Co-reporter:Yangqing Liu, Yu Zhou, Jing Li, Qian Wang, Qin Qin, Wei Zhang, Hiroyuki Asakura, Ning Yan, Jun Wang

Applied Catalysis B: Environmental 2017 Volume 209(Volume 209) pp:

Publication Date(Web):15 July 2017

DOI:10.1016/j.apcatb.2017.03.029

•Heterogeneous catalysis for benzene coupling with O2 into biphenyl is achieved.•It is achieved on the porous organic polymer (POP) supported Pd(II) sites.•Novel specific POP material is designed for single-atom dispersion of Pd(II) sites.•Atomically dispersed, highly electrophilic Pd(II) sites account for its activity.Synthesis of biphenyl directly from the oxidative coupling of benzene with O2 as the sole oxident is an atom-efficiency and environmental-friendly route, which is however unattainable as yet due to the most inert nature of sp2 CH bond in benzene ring, especailly for recyclable heterogeneous catalysis. In this work, single atomic dispersed palladium(II)-porous organic polymer (POP) catalyst with a high loading (>2 wt%) was constructed by anchoring Pd(II) species on the task-specifically designed POP support tethered with carboxyl acid and sulfonic acid groups. It exhibited efficient activity in the heterogeneous aerobic oxidative coupling of benzene with O2, giving the highest biphenyl yield of 26.1% so far. The high electrophilicity of thus anchored single atomic Pd(II) species is demonstrated, endowing the unprecedentedly maximum turnover number (TON) of 487 and turnover frequency (TOF) of 352 h−1 that expletively exceeds 15 and 88 times of previous heterogeneous catalyst. The catalyst can be facilely recycled and reused, and readily extendable to the conversion of other nonactivated arenes into corresponding biaryls. The designing strategy of POP materials developed in the study may provide a platform towards stable single atomic dispersed noble metal species with desirable electrophilicity as efficient catalysts for more sustainable CC formation-involved organic transformations.Download high-res image (216KB)Download full-size image

Hydrophilic mesoporous poly(ionic liquid)-supported Au–Pd alloy nanoparticles towards aerobic oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid under mild conditions

Co-reporter:Qian Wang;Wei Hou;Shuai Li;Jingyan Xie;Jing Li;Yu Zhou

Green Chemistry (1999-Present) 2017 vol. 19(Issue 16) pp:3820-3830

Publication Date(Web):2017/08/14

DOI:10.1039/C7GC01116D

Design of stable high-performance heterogeneous catalysts has become crucial for efficient catalytic conversion of renewable biomass into high value-added chemicals. Noble metal alloy nanoparticles (NPs) are of great interest due to their unique tunable structures and high activity. In this study, Au–Pd alloy NPs supported on hydrophilic mesoporous poly(ionic liquid) (MPIL) exhibited encouragingly high performance in the aerobic oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) in water under mild conditions. Nearly complete conversion of HMF is attained at a low temperature of 90 °C under atmospheric O2, resulting in 99% FDCA yield and high turnover number (TON) of up to 350. After reaction, the catalyst can be facilely recovered and reused with stable activity. Surface wettability plays a dominant role in the oxidation of HMF to FDCA, and synergistic alloy effect accounts for high activity. The results also show that MPILs are a promising support platform to achieve stable and efficient metal NPs through task-specific design of functional monomers.

Nanobelt α-CuV2O6 with hydrophilic mesoporous poly(ionic liquid): a binary catalyst for synthesis of 2,5-diformylfuran from fructose

Co-reporter:Wei Hou;Qian Wang;Zengjing Guo;Jing Li;Yu Zhou

Catalysis Science & Technology (2011-Present) 2017 vol. 7(Issue 4) pp:1006-1016

Publication Date(Web):2017/02/20

DOI:10.1039/C6CY02561G

Direct transformation of renewable biomass-derived carbohydrates into value-added chemicals usually involves a tandem reaction, and therefore demands catalysts with different versatile isolated active sites that can independently take action in each step. In this work, the task-specific binary catalyst nanobelt α-CuV2O6 with the mesoporous poly(ionic liquid) (MPIL) derived solid acid P(EVPI-Br) was constructed for the direct synthesis of 2,5-diformylfuran (DFF) from fructose. α-CuV2O6 gave a >99.9% DFF yield in the aerobic oxidation of 5-hydroxymethyl furfural (HMF) under atmospheric O2 (130 °C, 3 h). The binary catalyst α-CuV2O6 with P(EVPI-Br) afforded a 63.1% DFF yield in the one-pot and one-step conversion of fructose into DFF (O2, 135 °C, 3.5 h). Stepwise addition of the two catalyst units further increased the DFF yield to 76.1%. The hydrophilic surface of P(EVPI-Br) enabled the preferential adsorption of fructose on the acid sites whereas α-CuV2O6 showed strong adsorption of HMF but weak affinity to fructose. Such surface wettability-controlled adsorption features inhibited the oxidation of fructose and facilitated the transfer of HMF to the oxidative sites on α-CuV2O6 and its timely conversion into the final product, thanks to the high activity of α-CuV2O6. Moreover, facile catalyst recovery and good reusability were observed in the synthesis of DFF from both HMF and fructose. This work highlights the potential of manipulating the surface wettability of a binary catalyst towards an efficient multifunctional catalysis system for biomass-related tandem reactions.

Direct synthesis of V-containing all-silica beta-zeolite for efficient one-pot, one-step conversion of carbohydrates into 2,5-diformylfuran

Co-reporter:Wei Zhang;Wei Hou;Tongsuo Meng;Wenxia Zhuang;Jingyan Xie;Yu Zhou

Catalysis Science & Technology (2011-Present) 2017 vol. 7(Issue 24) pp:6050-6058

Publication Date(Web):2017/12/11

DOI:10.1039/C7CY01834G

Vanadium (V)-containing all-silica beta-zeolites (VSi-Beta) were directly synthesized using a dry-gel-conversion route, in which the gel was prepared from the acid-catalysed co-hydrolysis of a silica precursor and ammonium metavanadate. Besides the framework isolated V species, VSi-Beta contained tetrahedral [V2O7]4− and (VO3)nn− species that were bonded to the framework with a high dispersion. These V species resisted the over-oxidation of fructose and efficiently catalyzed the oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-diformylfuran (DFF). As a result, VSi-Beta demonstrated high activity in the one-pot and one-step conversion of fructose into DFF using atmospheric oxygen (O2) in the presence of sulfuric acid, affording a high yield of 86.3% and a maximum turnover number (TON) of 270. The catalyst can be easily recovered by filtration and exhibits good reusability. Various other carbohydrates (glucose, sucrose, inulin, raffinose, maltose and starch) were also effectively converted into DFF using VSi-Beta.

One-Pot Template-Free Synthesis of Cu–MOR Zeolite toward Efficient Catalyst Support for Aerobic Oxidation of 5-Hydroxymethylfurfural under Ambient Pressure

Co-reporter:Wei Zhang, Jingyan Xie, Wei Hou, Yangqing Liu, Yu Zhou, and Jun Wang

ACS Applied Materials & Interfaces 2016 Volume 8(Issue 35) pp:23122

Publication Date(Web):August 13, 2016

DOI:10.1021/acsami.6b07675

Supported catalysts are widely studied, and exploring new promising supports is significant to access more applications. In this work, novel copper-containing MOR-type zeolites Cu–MOR were synthesized in a one-pot template-free route and served as efficient supports for vanadium oxide. In the heterogeneous oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) with molecular oxygen (O2) under ambient pressure, the obtained catalyst demonstrated high yield (91.5%) and good reusability. Even under the ambient air pressure, it gave a DFF yield of 72.1%. Structure–activity relationship analysis indicated that the strong interaction between the framework Cu species and the guest V sites accounted for the remarkable performance. This work reveals that the Cu–MOR zeolite uniquely acts as the robust support toward well-performed non-noble metal heterogeneous catalyst for biomass conversion.Keywords: 5-hydroxymethylfurfural; biomass conversion; copper-containing zeolite; heterogeneous catalysis; hydrothermal synthesis

Hydroxyl-Exchanged Nanoporous Ionic Copolymer toward Low-Temperature Cycloaddition of Atmospheric Carbon Dioxide into Carbonates

Co-reporter:Zengjing Guo, Xiaochun Cai, Jingyan Xie, Xiaochen Wang, Yu Zhou, and Jun Wang

ACS Applied Materials & Interfaces 2016 Volume 8(Issue 20) pp:12812-12821

Publication Date(Web):May 4, 2016

DOI:10.1021/acsami.6b02461

An ionic copolymer catalyst with nanopores, large surface area, high ionic density, and superior basicity was prepared via the radical copolymerization of amino-functionalized ionic liquid bromide and divinylbenzene, followed with a hydroxyl exchange for removing bromonium. Evaluated in chemical fixation of CO2 with epoxides into cyclic carbonates in the absence of any solvent and basic additive, the nanoporous copolymer catalyst showed high and stable activity, superior to various control catalysts including the halogen-containing analogue. Further, high yields were obtained over a wide scope of substrates including aliphatic long carbon-chain alkyl epoxides and internal epoxide, even under atmospheric pressure and less than 100 °C for the majority of the substrates. On the basis of in situ Fourier transform infrared (FT-IR) investigation and density functional theory (DFT) calculation for the reaction intermediates, we proposed a possible reaction mechanism accounting for the superior catalytic activity of the ionic copolymer. The specifically prepared ionic copolymer material of this work features highly stable, noncorrosive, and sustainable catalysis and, thus, may be a new possibility for efficient chemical fixation of CO2 since it is an environmentally friendly, metal-free solid catalyst.

Hybrid of Polyoxometalate-Based Ionic Salt and N-Doped Carbon toward Reductant-Free Aerobic Hydroxylation of Benzene to Phenol

Co-reporter:Xiaochun Cai, Qian Wang, Yangqing Liu, Jingyan Xie, Zhouyang Long, Yu Zhou, and Jun Wang

ACS Sustainable Chemistry & Engineering 2016 Volume 4(Issue 9) pp:4986

Publication Date(Web):July 26, 2016

DOI:10.1021/acssuschemeng.6b01357

A novel carbon-based hybrid is composed of N-doped ordered mesoporous carbon (NC) and polyoxometalate (POM) based ionic salt (IL-POM), constructing the first efficient non-noble metal heterogeneous catalyst for reductant-free hydroxylation of benzene to phenol with molecular oxygen. Enhanced activity and reusability were achieved and were even better than the previous noble metal involved system. The newly task-specifically designed dicationic ionic liquid tethered with the nitrile group contributed to the high efficiency and heterogeneous property. Systematic structure–activity analysis revealed that the superior activity for this difficult reaction came from the simultaneous activation of benzene by NC and O2 by V species of IL-POM. This work suggests a new green reaction pathway toward heterogeneous aerobic hydroxylation of the Csp2-H bond in π-conjugated aromatic molecules.Keywords: Heterogeneous catalysis; Hydroxylation of benzene; Ionic liquid; Mesoporous carbon materials; Polyoxometalate

Fully-occupied Keggin type polyoxometalate as solid base for catalyzing CO2 cycloaddition and Knoevenagel condensation

Co-reporter:Weilin Ge, Xiaochen Wang, Lingyu Zhang, Lei Du, Yu Zhou and Jun Wang

Catalysis Science & Technology 2016 vol. 6(Issue 2) pp:460-467

Publication Date(Web):15 Oct 2015

DOI:10.1039/C5CY01038A

The highly negatively charged alkaline Keggin type polyoxometalate (POM) Na16[SiNb12O40]·xH2O (NaSiNb12) was synthesized and used as an efficient solid base catalyst for CO2 cycloaddition and Knoevenagel condensation reactions. This is the first report of the basicity of a fully-occupied POM with the Keggin type structure. Theoretical calculations by the density functional theory (DFT) method revealed the high negative NBO (natural bond orbital) charges (−0.919–−1.029) of the oxygen atoms in [SiNb12O40]16−, suggesting the existence of basicity, which was confirmed by CO2-TPD and the in situ FT-IR spectra of methanol absorbed on the POM solid. Catalysis tests indicated that the POM solid base was very efficient in catalyzing the heterogeneous Knoevenagel condensation, giving high conversion and selectivity for several substrates. The catalyst NaSiNb12 also presented high activity in the cycloaddition of CO2 to epichlorohydrin under relatively mild conditions (120 °C, 1 MPa) in the absence of any solvent or co-catalyst. This solid base catalyst could be reused five times without an obvious decrease in the conversion and selectivity.

Mg2+-derived mesoporous ultra-high silica twelve-membered-ring basic zeolites: straightforward synthesis and catalytic performance

Co-reporter:Jingyan Xie, Haimeng Wen, Wei Zhang, Yu Zhou and Jun Wang

CrystEngComm 2016 vol. 18(Issue 7) pp:1164-1173

Publication Date(Web):25 Jan 2016

DOI:10.1039/C5CE02075A

Mg2+-derived mesoporous ultra-high silica twelve-membered-ring zeolites with multiple topologies (MOR, BEA and MTW) were straightforwardly synthesized by a one-pot route, where the crucial step was the co-hydrolysis/condensation of silica source and magnesium salt under moderate acidic conditions. SiO2/Al2O3 ratios can be adjusted from ∼30 to as high as 410, thus generating superior basicity that was further improved by the incorporation of Mg species. A mesoporous structure was self-formed without the assistance of any template or special strategy. Catalysis tests showed high activity of these zeolites in a typical base reaction, Knoevenagel condensation, even for the bulky substrates due to the enhanced mass transfer arising from the mesopores. This methodology provides a promising approach towards target synthesis of valuable Mg2+-derived mesoporous ultra-high silica zeolites with tunable acid/base properties, which can even act as an efficient mesoporous zeolitic solid base.

Ionic self-assembly affords mesoporous ionic networks by crosslinking linear polyviologens with polyoxometalate clusters

Co-reporter:Guojian Chen, Wei Hou, Jing Li, Xiaochen Wang, Yu Zhou and Jun Wang

Dalton Transactions 2016 vol. 45(Issue 11) pp:4504-4508

Publication Date(Web):16 Feb 2016

DOI:10.1039/C6DT00070C

Ionic-bonded mesoporous ionic networks were prepared by the ionic self-assembly of polyoxometalate (POM) clusters with linear cationic polyviologens in water. The POM-enriched PMIN-2(V) possesses a high surface area up to 120 m2 g−1, exhibiting superior non-noble metal heterogeneous catalytic performance in the ambient aerobic selective oxidation of 5-hydroxymethylfurfural.

Mordenite zeolite with ultrahigh SiO2/Al2O3 ratio directly synthesized from ionic liquid-assisted dry-gel-conversion

Co-reporter:Zhipan Ma, Jingyan Xie, Jianlin Zhang, Wei Zhang, Yu Zhou, Jun Wang

Microporous and Mesoporous Materials 2016 Volume 224() pp:17-25

Publication Date(Web):April 2016

DOI:10.1016/j.micromeso.2015.11.007

•Direct synthesis of mordenite (MOR) zeolite with ultrahigh SiO2/Al2O3 is achieved.•Synthesis is carried out in ionic liquid assisted dry-gel-conversion route.•Tunable SiO2/Al2O3 ranging from 11 to as high as 263 is obtained on MOR zeolites.•Phase transition from MOR to MFI is observed in the synthesis.•The obtained high silica zeolites exhibit high thermal stability.SiO2/Al2O3 ratio (SAR) is one of the most important parameters for zeolite materials, and tuning of SAR towards required topology is crucial for applications of zeolites. Mordenite (MOR) zeolites normally possess the moderate SARs of about 4–32. In this work, a breakthrough for straightforward synthesis of high-silica MOR zeolites was achieved without using seed or fluoride additive, attaining well crystallized MOR with wide window of SARs in the range of 11–263, in which the ultrahigh SAR of 263 represented the highest value for MOR up to date. The synthesis relied on the gel preparation by acidic hydrolysis of the silica precursor with the ionic liquid (IL), 1-butyl-3-methylimidazolium bromide ([BMIm]Br), as the structure-direct-agent, followed by dry-gel-conversion (DGC). Besides mordenite, ZSM-5 could be also obtained from this route. Thermal stability tests demonstrated that the obtained ultrahigh-silica MOR zeolites preserved the crystalline structure up to 800 °C, and the higher SAR, the better thermal stability. Our synthesis largely expands the SAR range of MOR zeolites and provides a series of highly thermal stable high-silica MOR zeolites as promising catalyst supports.

Highly Active Palladium-Based Catalyst System for the Aerobic Oxidative Direct Coupling of Benzene to Biphenyl

Co-reporter:Yangqing Liu;Xiaochen Wang;Xiaochun Cai;Guojian Chen;Jing Li;Dr. Yu Zhou;Dr. Jun Wang

ChemCatChem 2016 Volume 8( Issue 2) pp:448-454

Publication Date(Web):

DOI:10.1002/cctc.201500951

Abstract

A highly efficient Pd-containing catalytic system for the intermolecular direct C−H homocoupling of benzene to biphenyl has been developed. The catalytic system was composed of Pd(OAc)₂ with trifluoromethanesulfonic acid (TfOH) as an additive and O₂ as the sole oxygen source in the absence of any metal-containing cocatalyst. An excellent efficiency of Pd^II with the acidic additive was attained in the aerobic oxidation of benzene to biphenyl. A high yield (25.3 %) and selectivity (98 %) were achieved by using a small amount of Pd(OAc)₂ (0.07 mol %) and TfOH, which gave a high turnover number (180) for Pd species. Theoretical calculation by DFT and UV/Vis absorption spectra illustrated that the formation of electropositive Pd^II species in the presence of TfOH contributed to the high efficiency of the catalytic system.

Heterogeneous conversion of CO2 into cyclic carbonates at ambient pressure catalyzed by ionothermal-derived meso-macroporous hierarchical poly(ionic liquid)s

Co-reporter:Xiaochen Wang, Yu Zhou, Zengjing Guo, Guojian Chen, Jing Li, Yuming Shi, Yangqing Liu and Jun Wang

Chemical Science 2015 vol. 6(Issue 12) pp:6916-6924

Publication Date(Web):27 Aug 2015

DOI:10.1039/C5SC02050F

Meso-macroporous hierarchical poly(ionic liquid)s (MPILs) with extremely high ionic site densities and tunable pore structures were ionothermally synthesized through the free radical self-polymerization of our newly designed rigid bis-vinylimidazolium salt monomer. The synthesis avoided the use of any templates, gave a high yield (>99%) and allowed recycling of the IL solvent; thus it is facile, atom-efficient, environmentally friendly and sustainable. The synthesized MPILs possessed distinctive features of polycation matrices, abundant halogen anions, and large surface areas. They not only presented enhanced CO2 capture, but led to breakthroughs in the heterogeneous catalytic conversion of CO2 into cyclic carbonates: (1) unprecedented high activity at atmospheric pressure and low temperature; (2) good substrate compatibility, even being active towards the extremely inert aliphatic long carbon-chain alkyl epoxides. This result renders the first occasion of a metal–solvent–additive free recyclable heterogeneous cycloaddition of CO2 at such mild conditions.

Direct Carbonization of Cyanopyridinium Crystalline Dicationic Salts into Nitrogen-Enriched Ultra-Microporous Carbons toward Excellent CO2 Adsorption

Co-reporter:Guojian Chen, Xiaochen Wang, Jing Li, Wei Hou, Yu Zhou, and Jun Wang

ACS Applied Materials & Interfaces 2015 Volume 7(Issue 33) pp:18508

Publication Date(Web):August 1, 2015

DOI:10.1021/acsami.5b04842

A family of nitrogen-enriched ultramicroporous carbon materials was prepared by direct carbonization of task-specifically designed molecular carbon precursors of cyanopyridinium-based crystalline dicationic salts (CISs). Varying the molecular structure of CISs, large surface area (918 m2 g–1), high N content (20.10 wt %), and narrow distributed ultramicropores (0.59 nm) can be simultaneously achieved on the sample PCN-14 derived from methyl-linked 4-cyanopyridinium D[4-CNPyMe]Tf2N. It therefore exhibited exceptional performance in greenhouse gas CO2 capture, i.e., simultaneously possessing (1) high CO2 adsorption uptakes: 5.33 mmol g–1 at 273 K, and 3.68 mmol g–1 at 298 K (both at 1.0 bar); (2) unprecedented selectivity of CO2 versus N2: 156; and (3) a high adsorption ratio of CO2 to N2: 148 (at 1.0 bar). This is the first time such a high selectivity and adsorption ratio over carbon materials has been achieved, which is among the highest values over solid adsorbents.Keywords: CO2 capture; ionic liquids; microporous materials; molecular precursors; porous carbon

A hierarchical meso-macroporous poly(ionic liquid) monolith derived from a single soft template

Co-reporter:Chenjue Gao, Guojian Chen, Xiaochen Wang, Jing Li, Yu Zhou and Jun Wang

Chemical Communications 2015 vol. 51(Issue 24) pp:4969-4972

Publication Date(Web):12 Jan 2015

DOI:10.1039/C4CC09091H

A hierarchical meso-macroporous poly(ionic liquid) monolith with tunable pore structure is synthesized through free radical self-polymerization of 1-allyl-3-vinylimidazolium ionic liquid by using the tri-block copolymer P123 as the soft template. The obtained polymeric matrix can highly disperse heteropolyanions through anion-exchange, exhibiting superior catalytic activity in cis-cyclooctene epoxidation with H2O2.

Polyoxometalate-based phase transfer catalysis for liquid–solid organic reactions: a review

Co-reporter:Yu Zhou, Zengjing Guo, Wei Hou, Qian Wang and Jun Wang

Catalysis Science & Technology 2015 vol. 5(Issue 9) pp:4324-4335

Publication Date(Web):21 Jul 2015

DOI:10.1039/C5CY00674K

Phase transfer catalysis combines the advantages of homogeneous and heterogeneous catalysts and therefore attracts ever-growing interest for environmentally-friendly sustainable processes. Polyoxometalates (POMs) are a class of molecular metal oxides showing numerous applications in various catalytic processes due to their unique acid/base and redox features. The tunable molecular structures of POM anions and countercations bring about facile adjusting of POMs' physical and chemical properties including solubility, through which many POM-based phase transfer catalysts are fabricated, such as reaction-controlled, temperature-responsive and photo-sensitive phase transfer catalysts. This mini-review summarizes the recent progress in POM-based phase transfer catalysis for liquid–solid organic reactions.

Efficient and recyclable multi-cationic polyoxometalate-based hybrid catalyst for heterogeneous cyclohexane oxidation with H2O2

Co-reporter:Shuang Xue, Guojian Chen, Zhouyang Long, Yu Zhou and Jun Wang

RSC Advances 2015 vol. 5(Issue 25) pp:19306-19314

Publication Date(Web):09 Feb 2015

DOI:10.1039/C4RA15921G

A polyoxometalate-based organic–inorganic hybrid was prepared by ionic self-assembly of the ionic liquid precursor N,N′-bis-2-aminoethyl-4,4′-bipyridinium dibromide dihydrobromide ([DPyAM]Br2·2HBr) with the Keggin-structured V-substituted polyoxometalate H5PMo10V2O40 (H5PMoV2). The composition, electronic and porous structure of the resultant hybrid [DPyAM(H2)]1.25PMoV2 were demonstrated by CHN elemental analysis, 1H NMR, TG, SEM, XRD, FT-IR, UV-vis, ESR, and nitrogen sorption techniques. Catalytic tests showed that the hybrid was a highly active heterogeneous catalyst for cyclohexane oxidation with hydrogen peroxide, giving a yield of KA oil (a mixture of cyclohexanol and cyclohexanone) of ca. 29.4% with high turnover number (TON) of 2940 using very low catalyst dose (0.01 mol% vs. substrate). The catalyst can be conveniently separated by filtration and reused without observing a significant decrease in activity. The influences of reaction conditions were systematically investigated and a possible catalysis mechanism was proposed for understanding the highly efficient heterogeneous catalytic behavior.

Hydrophobic Mesoporous Poly(ionic liquid)s towards Highly Efficient and Contamination-Resistant Solid-Base Catalysts

Co-reporter:Xiaochen Wang;Jing Li;Guojian Chen;Zengjing Guo;Dr. Yu Zhou;Dr. Jun Wang

ChemCatChem 2015 Volume 7( Issue 6) pp:993-1003

Publication Date(Web):

DOI:10.1002/cctc.201402995

Abstract

Mesoporous poly(ionic liquid)s were synthesized by radical copolymerization of the ionic liquid 1-aminoethyl-3-vinylimidazolium bromide with divinylbenzene plus the ion exchange of bromide anions with hydroxyls. Characterizations revealed the high ionic liquid content, large surface area, and hydrophobicity for the sample prepared with equimolar amounts of ionic liquid and divinylbenzene, with good accessibility to organic compounds and resistance to CO₂/H₂O contamination. The mesoporous copolymer behaved as a superior and recyclable solid-base catalyst for solvent-free Knoevenagel condensation of benzaldehyde with ethyl cyanoacetate, giving the much higher turnover frequency of 304 h⁻¹ (yield 99 %, 0.5 h) than those of the nonporous analogues, commercial strong basic resins, and even homogeneous NaOH. The high activity was confirmed by Knoevenagel condensation with various substrates and Claisen–Schmidt condensation. A possible synergistic Lewis–Brønsted dual-base-center mechanism is proposed for understanding the catalytic behavior.

Back Cover: Hydrophobic Mesoporous Poly(ionic liquid)s towards Highly Efficient and Contamination-Resistant Solid-Base Catalysts (ChemCatChem 6/2015)

Co-reporter:Xiaochen Wang;Jing Li;Guojian Chen;Zengjing Guo;Dr. Yu Zhou;Dr. Jun Wang

ChemCatChem 2015 Volume 7( Issue 6) pp:

Publication Date(Web):

DOI:10.1002/cctc.201590035

One-Pot Synthesis of Zeolitic Strong Solid Bases: A Family of Alkaline-Earth Metal-Containing Silicalite-1

Co-reporter:Dr. Yu Zhou;Yanhua Jin;Meng Wang;Wei Zhang;Jingyan Xie;Dr. Jing Gu;Dr. Haimeng Wen; Jun Wang;Dr. Luming Peng

Chemistry - A European Journal 2015 Volume 21( Issue 43) pp:15412-15420

Publication Date(Web):

DOI:10.1002/chem.201501894

Abstract

Fabricating stable strong basic sites in well-preserved crystallized zeolitic frameworks still remains a difficult issue. Here, we reported a family of MFI-type metallosilicate zeolites, AeS-1 (Ae: alkaline-earth metal ions of Mg, Ca, Sr or Ba; S-1: silicalite-1) through a direct one-pot hydrothermal method involving the acidic co-hydrolysis/condensation of the silica precursor with the Ae salts. Step-by-step full characterizations were designed and conducted for in-depth discussion of the Ae status in AeS-1. Strong basicity (H_≈22.5–26.5) was detected in AeS-1. The basicity was further confirmed by CO₂ sorption measurements, ¹³C NMR spectra of chloroform-adsorbed samples, and ¹H¹³C and ¹H²⁹Si cross-polarization magic-angle spinning NMR spectra of ethyl cyanoacetate-adsorbed samples. The results of Knoevenagel condensations demonstrated the excellent solid base catalysis of AeS-1, which showed high activity, reusability, and shape-selectivity, all of which are explained by Ae-derived zeolitic intracrystalline strong basic sites.

Mesoporous Polyoxometalate-Based Ionic Hybrid As a Triphasic Catalyst for Oxidation of Benzyl Alcohol with H2O2 on Water

Co-reporter:Guojian Chen, Yu Zhou, Zhouyang Long, Xiaochen Wang, Jing Li, and Jun Wang

ACS Applied Materials & Interfaces 2014 Volume 6(Issue 6) pp:4438

Publication Date(Web):March 6, 2014

DOI:10.1021/am5001757

A self-assembled mesoporous polyoxometalate-based ionic hybrid catalyst [TMGHA]2.4H0.6PW was prepared by combination of alcohol amino-tethered guanidinium ionic liquid [TMGHA]Cl with Keggin phosphotungstic acid H3PW12O40 (PW). Nitrogen sorption experiment validated the formation of mesostructure with moderate BET surface area, and scanning and transmission electron microscopy (SEM and TEM) showed a fluffy coral-shaped morphology for the hybrid. The contact angle test displayed that the hybrid owned hydrophilic–hydrophobic balanced surface that exhibited well wettability for both water and organic substrate like benzyl alcohol. Therefore, the hybrid can efficiently catalyze the water-mediated triphasic oxidation of benzyl alcohol with H2O2. During the reaction, the triphase catalytic system showed a special “on water” effect mainly due to the suitable mesostructure and surface wettability, thus providing some clues for the preparation of green heterogeneous catalyst.Keywords: ionic liquid; mesoporous; on water; oxidation of alcohols; polyoxomeatalate; triphase catalysis;

Amphiphilic Polyoxometalate-Paired Polymer Coated Fe3O4: Magnetically Recyclable Catalyst for Epoxidation of Bio-Derived Olefins with H2O2

Co-reporter:Yan Leng, Jiwei Zhao, Pingping Jiang, and Jun Wang

ACS Applied Materials & Interfaces 2014 Volume 6(Issue 8) pp:5947

Publication Date(Web):April 2, 2014

DOI:10.1021/am500987s

An amphiphilic composite with magnetic Fe3O4 core and dodecylamine-modified polyoxometalate-paired poly(ionic liquid) shell was synthesized and characterized by 1H NMR, thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, UV–vis spectroscopy, X-ray diffraction (XRD), and digital microscopy. Catalytic tests for H2O2-based epoxidation of bioderived olefins, along with comparisons to various counterparts, demonstrate well that this newly designed catalyst exhibits high activity and selectivity, coupled with convenient magnetic recovery, and effective regeneration. The unique amphiphilic catalyst structure and the intramolecular charge transfer between amino groups and heteropolyanions are revealed to be responsible for the catalyst’s excellent performances in epoxidation reactions.Keywords: amphiphilic composite; epoxidation; heterogeneous catalysis; poly(ionic liquid); polyoxometalate;

Morphology-Controlled Preparation of Heteropolyanion-Derived Mesoporous Solid Base

Co-reporter:Xiaochen Wang, Yu Zhou, Guojian Chen, Jing Li, Zhouyang Long, and Jun Wang

ACS Sustainable Chemistry & Engineering 2014 Volume 2(Issue 7) pp:1918

Publication Date(Web):June 11, 2014

DOI:10.1021/sc500259v

Heteropolyanion-derived mesoporous solid base catalysts were prepared by designing the basic ionic liquid (IL) N-3-[2-(2-aminoethylamino)ethylamino]-2-hydroxypropyl)pyridinium chloride ([TAHpy]Cl) to assemble with Keggin-structured sodium phosphotungstate (Na3PW12O40) in the aqueous solution containing organic base diethylenetriamine (DETA). The obtained hybrids were characterized by various techniques such as thermogravimetric analysis, elemental analysis, Fourier transform infrared spectroscopy, scanning electron microscope, and nitrogen adsorption experiments. In the synthesis, the concentration of DETA was adjusted to control the morphology and mesostructure of the obtained basic hybrids, and concentrated DETA caused the formation of the mesoporous solid base. The structure analysis indicated that the obtained hybrid demonstrated a piece-like shape in macroscopical size, and these species were assembled by relative uniform small nanoellipsoids with the diameter of ∼50 nm, which forms a loosely packed structure. Assessed in the liquid–solid heterogeneous Knoevenagel condensation, the mesoporous solid base with a morphology of loosely packed nanoparticles presented superior activity, which was about 14 times higher than the nonporous analogues with large block morphology. A possible catalytic mechanism is proposed to explain the efficient catalytic performance.Keywords: Heterogeneous catalyst; Ionic liquids; Mesoporous solid base; Morphology and pore control; Polyoxometalate;

(Ionic liquid)-derived morphology control of Nb2O5 materials and their photocatalytic properties

Co-reporter:Lei Du, Zhouyang Long, Haimeng Wen, Weilin Ge, Yu Zhou and Jun Wang

CrystEngComm 2014 vol. 16(Issue 38) pp:9096-9103

Publication Date(Web):31 Jul 2014

DOI:10.1039/C4CE00987H

Pseudo-hexagonal TT phase Nb2O5 with various uniform crystalline morphologies such as nanorods, fibers, flower-like clusters, bundles, and porous spheres are fabricated using a hydrothermal synthesis route with ionic liquids as guiding agents. Among these morphologies, nanorods, flower-like clusters and bundles are firstly observed for Nb2O5. The morphology control is easily achieved by variation of the ionic liquid concentration. A primary mechanism study indicates a similar variation regulation for morphologies of Nb2O5 from rods to fibers and then spheres, when the ionic liquid concentration increases independent of the kind of ionic liquids. The photocatalytic activities of the obtained Nb2O5 with various morphologies are evaluated using the photodegradation of methylene blue. The results indicate that the catalytic performance depends on the morphology, and nanorods, fibers and clusters show superior activities even in a concentrated methylene blue solution. This study develops a facile way to control the crystalline morphology of Nb2O5 over a wide range and provides efficient photocatalysts using morphology control.

Pure-silica ZSM-22 zeolite rapidly synthesized by novel ionic liquid-directed dry-gel conversion

Co-reporter:Haimeng Wen, Yu Zhou, Jingyan Xie, Zhouyang Long, Wei Zhang and Jun Wang

RSC Advances 2014 vol. 4(Issue 91) pp:49647-49654

Publication Date(Web):22 Sep 2014

DOI:10.1039/C4RA07627C

Shortening the crystallization process of zeolites is significant for their applications because of the energy savings. Here, we report a rapid synthetic route for pure-silica ZSM-22 zeolite with TON topology. The synthesis was achieved by dry-gel conversion, where the dry gel was prepared under an unusual acidic condition for hydrolyzing the silica precursor with 1,3-alkylimidazolium ionic liquid as the structure-directing agent (SDA). Highly crystallized pure-silica ZSM-22 can be synthesized within 2 days of crystallization, dramatically shorter than 10% of the conventional hydrothermal strategy. Using a similar procedure, Al-containing ZSM-22 can also be synthesized by simply adding aluminum salt in the initial gel. In addition, understanding of the structure-directing role of ionic liquids is attempted through characterizations of IR, TG, 1H and 13C NMR spectra.

A new polyoxometalate-based Mo/V coordinated crystalline hybrid and its catalytic activity in aerobic hydroxylation of benzene

Co-reporter:Weilin Ge, Zhouyang Long, Xiaochun Cai, Qian Wang, Yu Zhou, Yan Xu and Jun Wang

RSC Advances 2014 vol. 4(Issue 86) pp:45816-45822

Publication Date(Web):08 Sep 2014

DOI:10.1039/C4RA06736C

A novel self-assembled polyoxometalate-based Mo/V coordinated crystalline organic–inorganic hybrid compound [Mo2V2O8(2,2′-bpy)6][HPMo10V2O40]·2H2O (bpy = bipyridyl) was hydrothermally synthesized by introducing polyoxometalate into a metal–organic unit containing metal nodes and 2,2′-bipyridyl ligands. The unit of the crystal consists of one Keggin-structure heteropolyoxoanion [HPMo10V2O40]4−, one tetranuclear organic–metal coordination cation [Mo2V2O8(2,2′-bpy)6]4+ and two water molecules. The crystalline hybrid presents heterogeneous catalytic performance and superior activity towards benzene hydroxylation with molecular oxygen as the oxidant and ascorbic acid as the sacrificial reducing agent, giving a phenol yield of 12.5% and a high TON (turnover number) of 41. The result indicates that the polyoxometalate-based crystalline organic–inorganic hybrid compound provides an efficient heterogeneous catalyst for the liquid-phase aerobic hydroxylation of benzene to phenol.

Recent advances in polyoxometalate-based heterogeneous catalytic materials for liquid-phase organic transformations

Co-reporter:Yu Zhou, Guojian Chen, Zhouyang Long and Jun Wang

RSC Advances 2014 vol. 4(Issue 79) pp:42092-42113

Publication Date(Web):12 Aug 2014

DOI:10.1039/C4RA05175K

Polyoxometalates (POMs) are a unique class of molecular metal oxides with a tunable structure at the atomic level. They have demonstrated various potential applications in various fields. In particular, POMs have been widely used as catalysts, due to their facilely modified acid–base properties and redox potential through molecular designing. Normally, POMs can be utilized as both homogeneous and heterogeneous catalysts, where the former favors high activity, while the latter benefits facile separation of the catalysts. Faced with the requirement for sustainable development, significant effort has been made in the preparation of POM-based heterogeneous catalysts. This review focuses on the recent developments in heterogeneous strategies of POM-based catalysts and their applications in liquid organic reactions.

Pore structure controllable synthesis of mesoporous poly(ionic liquid)s by copolymerization of alkylvinylimidazolium salts and divinylbenzene

Co-reporter:Xuping Feng, Chenjue Gao, Zengjing Guo, Yu Zhou and Jun Wang

RSC Advances 2014 vol. 4(Issue 45) pp:23389-23395

Publication Date(Web):15 May 2014

DOI:10.1039/C4RA03163F

By chain radical copolymerizations of imidazolium-type ionic liquids and divinylbenzene, mesoporous poly(ionic liquid)s with tunable pore structures were synthesized. The pore size and copolymer composition involving the ionic liquid and divinylbenzene can be controlled through varying the solvents. A series of 3-alkyl-1-vinylimidazolium bromide ionic liquids with different carbon chain lengths of 4, 6, 8, 12 and 16 in the alkyl groups were used in the synthesis, which is significant for the formation of pore structures. The obtained poly(ionic liquid)s were characterized by BET, CHN elemental analysis, FT-IR and UV-vis spectra. The results indicated that poly(ionic liquid)s with varied mesopores and compositions can be facilely achieved in this system. CO2 sorption capability and sorption–desorption cycling were tested, showing superior adsorption capability for CO2 and durable sorption properties.

Dual-sulfonated dipyridinium phosphotungstate catalyst for liquid-phase Beckmann rearrangement of cyclohexanone oxime

Co-reporter:Dan Mao, Zhouyang Long, Yu Zhou, Jing Li, Xiaochen Wang and Jun Wang

RSC Advances 2014 vol. 4(Issue 30) pp:15635-15641

Publication Date(Web):17 Mar 2014

DOI:10.1039/C4RA00552J

The heteropolyanion (HPA)-based ionic liquid (IL) hybrid was prepared by pairing Keggin-structured HPA of the phosphotungstate anion PW12O403− (PW) with dual-sulfonated 4,4′-dipyridinium IL-cation [DPySO3H]2+. The obtained powdered IL–HPA hybrid material [DPySO3H]1.5PW was characterized and catalytically assessed in Beckmann rearrangement of cyclohexanone-oxime to ε-caprolactam. Under the optimized reaction conditions: 10 mol% catalyst, 130 °C, 2 h, benzonitrile as the solvent, and without the environmentally harmful cocatalyst ZnCl2, [DPySO3H]1.5PW exhibits 100% conversion and 73.0% selectivity, remarkably higher than control catalysts involving other HPA-anions or the partially proton-substituted IL-cation. Moreover, the catalyst [DPySO3H]1.5PW can be isolated and reused via filtration from the liquid–solid heterogeneous reaction mixture demonstrated by the four-run recycling test.

Morphology-controlled synthesis of large mordenite crystals

Co-reporter:Yaming Mao, Yu Zhou, Haimeng Wen, Jingyan Xie, Wei Zhang and Jun Wang

New Journal of Chemistry 2014 vol. 38(Issue 7) pp:3295-3301

Publication Date(Web):08 May 2014

DOI:10.1039/C3NJ01601C

The morphology-controlled synthesis of mordenite (MOR) zeolites was achieved using the acidic hydrolysis route, which was started by acid-catalyzed hydrolysis of tetraethylorthosilicate (TEOS), followed by switching the synthetic gel to basic conditions for hydrothermal crystallization. The synthesis by using tetraethylammonium hydroxide as the template resulted in a series of large MOR crystals with different morphologies, such as bulky sphere, circular pie, flat prism, hexagonal star-like prism and ellipsoid. Moreover, column, elongated spindle, short spindle, petal and circular pie shaped MOR crystals could be obtained without using an organic template in the above synthetic route. Among these morphologies, the bulky sphere, hexagonal star-like prism and petal shaped crystals were generated on MOR zeolites for the first time. The obtained products were characterized by XRD, SEM and N2 adsorption experiments. Various synthetic parameters were systematically investigated, including hydrolysis conditions for TEOS, molar composition of the initial gel, crystallization time and temperature. The results demonstrated that MOR zeolites can be synthesized through the acidic hydrolysis route, and their morphology can be facilely controlled through tuning the elemental synthetic conditions.

Ionic-Liquid-Functionalized Polyoxometalates for Heterogeneously Catalyzing the Aerobic Oxidation of Benzene to Phenol: Raising Efficacy through Specific Design

Co-reporter:Zhouyang Long;Dr. Yu Zhou;Weilin Ge;Guojian Chen;Jingyan Xie;Qian Wang ; Jun Wang

ChemPlusChem 2014 Volume 79( Issue 11) pp:1590-1596

Publication Date(Web):

DOI:10.1002/cplu.201402186

Abstract

By combining nitrile-tethered pyridinium-based ionic liquid dication with the polyoxometalate anion of Keggin H₅PMo₁₀V₂O₄₀ (PMoV₂) through precipitation in aqueous solution, an organic–inorganic hybrid catalyst 1,1′-(butane-1,4-diyl)-bis(3-cyanopyridine)–PMoV₂ was prepared for heterogeneous hydroxylation of benzene to phenol with O₂ and ascorbic acid as the oxidant and reductant, respectively. The hybrid catalyst not only gave the high phenol yield of 13.0 % under the optimized reaction conditions, but also exhibited high potential for reusability. The catalyst and its analogue samples were characterized by elemental analysis, Fourier transform infrared spectroscopy, electron spin resonance spectroscopy, X-ray diffraction, scanning electron microscopy, and nitrogen adsorption–desorption analysis. The structure–activity relationship is discussed according to the characterization and density functional theory calculation results.

Pd nanoparticles encapsulated into mesoporous ionic copolymer: Efficient and recyclable catalyst for the oxidation of benzyl alcohol with O2 balloon in water

Co-reporter:Qian Wang, Xiaochun Cai, Yangqing Liu, Jingyan Xie, Yu Zhou, Jun Wang

Applied Catalysis B: Environmental (15 July 2016) Volume 189() pp:242-251

Publication Date(Web):15 July 2016

DOI:10.1016/j.apcatb.2016.02.067

Direct synthesis of sulfonic group tethered mesoporous poly(ionic liquid) for catalyzing deoximation reactions

Co-reporter:Difan Li, Jing Li, Dan Mao, Haimeng Wen, Yu Zhou, Jun Wang

Materials Chemistry and Physics (1 March 2017) Volume 189() pp:118-126

Publication Date(Web):1 March 2017

DOI:10.1016/j.matchemphys.2016.12.067

A hierarchical meso-macroporous poly(ionic liquid) monolith derived from a single soft template

Co-reporter:Chenjue Gao, Guojian Chen, Xiaochen Wang, Jing Li, Yu Zhou and Jun Wang

Chemical Communications 2015 - vol. 51(Issue 24) pp:NaN4972-4972

Publication Date(Web):2015/01/12

DOI:10.1039/C4CC09091H

Heterogeneous conversion of CO2 into cyclic carbonates at ambient pressure catalyzed by ionothermal-derived meso-macroporous hierarchical poly(ionic liquid)s

Co-reporter:Xiaochen Wang, Yu Zhou, Zengjing Guo, Guojian Chen, Jing Li, Yuming Shi, Yangqing Liu and Jun Wang

Chemical Science (2010-Present) 2015 - vol. 6(Issue 12) pp:NaN6924-6924

Publication Date(Web):2015/08/27

DOI:10.1039/C5SC02050F

Ionic self-assembly affords mesoporous ionic networks by crosslinking linear polyviologens with polyoxometalate clusters

Co-reporter:Guojian Chen, Wei Hou, Jing Li, Xiaochen Wang, Yu Zhou and Jun Wang

Dalton Transactions 2016 - vol. 45(Issue 11) pp:NaN4508-4508

Publication Date(Web):2016/02/16

DOI:10.1039/C6DT00070C

Fully-occupied Keggin type polyoxometalate as solid base for catalyzing CO2 cycloaddition and Knoevenagel condensation

Co-reporter:Weilin Ge, Xiaochen Wang, Lingyu Zhang, Lei Du, Yu Zhou and Jun Wang

Catalysis Science & Technology (2011-Present) 2016 - vol. 6(Issue 2) pp:NaN467-467

Publication Date(Web):2015/10/15

DOI:10.1039/C5CY01038A

Polyoxometalate-based phase transfer catalysis for liquid–solid organic reactions: a review

Co-reporter:Yu Zhou, Zengjing Guo, Wei Hou, Qian Wang and Jun Wang

Catalysis Science & Technology (2011-Present) 2015 - vol. 5(Issue 9) pp:NaN4335-4335

Publication Date(Web):2015/07/21

DOI:10.1039/C5CY00674K

Nanobelt α-CuV2O6 with hydrophilic mesoporous poly(ionic liquid): a binary catalyst for synthesis of 2,5-diformylfuran from fructose

Co-reporter:Wei Hou, Qian Wang, Zengjing Guo, Jing Li, Yu Zhou and Jun Wang

Catalysis Science & Technology (2011-Present) 2017 - vol. 7(Issue 4) pp:NaN1016-1016

Publication Date(Web):2017/01/19

DOI:10.1039/C6CY02561G

CAS:1225386-49-1

CAS:948863-66-9

CAS:888502-48-5

1-(2-aminoethyl)-Pyridinium bromide

1,3-bis(3-cyanopropyl)-2,3-dihydro-1h-imidazol-1-ium Chloride

CAS:813458-73-0

1,3-bis(3-cyanopropyl)-2,3-dihydro-1h-imidazol-1-ium Chloride

1H-Imidazole, 1,1'-(1,3-phenylene)bis[2-methyl-

CAS:683786-06-3

1H-Imidazole, 1,1'-(1,3-phenylene)bis[2-methyl-

1H-Imidazolium, 1,1'-(1,4-butanediyl)bis[3-butyl-, dibromide

CAS:678138-62-0

1H-Imidazolium, 1,1'-(1,4-butanediyl)bis[3-butyl-, dibromide

1H-Imidazolium, 1-butyl-3-ethenyl-, chloride

CAS:657394-63-3

1H-Imidazolium, 1-butyl-3-ethenyl-, chloride

Cyclopentanone, 2-[hydroxy(4-nitrophenyl)methyl]-

CAS:205759-66-6

Cyclopentanone, 2-[hydroxy(4-nitrophenyl)methyl]-

CAS:184840-84-4

Benzene, 1-methoxy-4-methyl-2-(phenylmethyl)-

CAS:179308-40-8

Benzene, 1-methoxy-4-methyl-2-(phenylmethyl)-