- High Chemoselectivity in the Construction of Aryl Methyl Sulfones via an Unexpected C-S Bond Formation between Sulfonylhydrazides and Dimethyl Phosphite
-
A highly chemoselective route to aryl methyl sulfones via an unexpected C S bond formation between sulfonylhydrazides and dimethyl phosphite catalyzed by NaI under mild conditions has been established. This transformation provides an alternative and metal-free pathway to acquire various aryl methyl sulfones in good to excellent yields. Notably, dimethyl phosphite was employed as a stable and readily available alkyl source.
- Liu, Teng,Yu, Shiwen,Shen, Xiang,Li, Yixian,Liu, Jianjun,Huang, Chao,Cheng, Feixiang
-
p. 153 - 160
(2021/10/04)
-
- Polyoxometalate-Based Organic-Inorganic Hybrids as Heterogeneous Catalysts for Cycloaddition of CO2with Epoxides and Oxidative Desulfurization Reactions
-
Self-assembly of polyoxometalates, transition metal salts, and 2,6-bis(2′-pyridyl)-4-hydroxypyridine (LOH) obtained four organic-inorganic hybrids [Co2.5(LOH)(LO)2(H2O)2(PW12O39)]·3CH3CN·2OH (1), [Zn1.5(LOH)3]·(PMo12O40)·CH3OH·2H2O (2), [Cd1.5(LOH)3]·(PW12O40)·2CH3OH·1.5H2O (3), and [Mn(LOH)2]·(PW12O40)·2CH3CN·H3O (4). Hybrid 1 exhibits an extended chain, which could be further connected into a 3D supramolecular architecture by H-bonds. Hybrids 2-4 feature monomolecular structures, which are further bridged via H-bonds to yield charming 3D supramolecular structures. Noteworthy, 1 and 2 can be employed as recyclable and highly efficient heterogeneous catalysts. The activated 1 displays a high catalytic activity for the cycloaddition reaction of CO2 and epoxides. Hybrid 2 exhibits an excellent catalytic performance for the oxidative desulfurization reaction.
- Zhao, Yu-Qing,Liu, Ying-Ying,Ma, Jian-Fang
-
p. 1019 - 1027
(2021/01/13)
-
- Self-Assembled Polyoxometalate-Based Metal-Organic Polyhedra as an Effective Heterogeneous Catalyst for Oxidation of Sulfide
-
Two polyoxovanadate-based metal-organic polyhedra with octahedral (oct) and rhombic dodecahedral (rdo) geometries have been constructed from a concave molecular building block and linear and triangular carboxylate ligands. VMOP-7 is constructed from {V5O9Cl} SBU and a linear anthracene-9,10-dicarboxylic acid ligand in which all the anthracene groups are perpendicular to the edge of the octahedron. Such an arrangement mode can effectively reduce the steric hindrance between ligands. VMOP-8 is constructed from {V5O9Cl} SBU and a triangular biphenyl 3,4,5-tricarboxylate ligand, which exhibits an elongated rhombic dodecahedral configuration due to the geometry of the ligand. Furthermore, VMOP-8 can serve as a heterogeneous catalyst and exhibits efficient and common catalytic activity for oxidative desulfurization.
- Gan, Hong-Mei,Qin, Chao,Zhao, Liang,Sun, Chunyi,Wang, Xing-Long,Su, Zhong-Min
-
p. 1028 - 1034
(2021/01/26)
-
- Synthesis of a light-harvesting ruthenium porphyrin complex substituted with BODIPY units. Implications for visible light-promoted catalytic oxidations
-
A light-harvesting ruthenium porphyrin substituted covalently with four boron-dipyrrin (BODIPY) moieties has been synthesized and studied. The resulting complex showed an efficient decarbonylation reaction predominantly due to a photo-induced energy transfer process. Chemical oxidation of the ruthenium(ii) BODIPY-porphyrin afforded a high-energytrans-dioxoruthenium(vi) species that is one order of magnitude more reactive towards alkene oxidation than those analogues supported by conventional porphyrins. In the presence of visible light, the ruthenium(ii) BODIPY-porphyrin displayed remarkable catalytic activity toward sulfide oxidation and alkene epoxidation using iodobenzene diacetate [PhI(OAc)2] and 2,6-dichloropyridineN-oxide (Cl2pyNO) as terminal oxidants, respectively. The findings in this work highlight that porphyrin-BODIPY conjugated metal complexes are potentially useful for visible light-promoted catalytic oxidations.
- Malone, Jonathan,Klaine, Seth,Alcantar, Christian,Bratcher, Fox,Zhang, Rui
-
p. 4977 - 4985
(2021/03/26)
-
- Assembly of polyoxometalate-thiacalix[4]arene-based inorganic-organic hybrids as efficient catalytic oxidation desulfurization catalysts
-
Self-assembly of polyoxometalates, Ni(ii)/Ag(i) cations and tetra-[5-(mercapto)-1-methyltetrazole]-thiacalix[4]arene (L) yielded three inorganic-organic hybrids, namely, [Ni3L2(CH3OH)6(H2O)4][PMo12O40]2·3CH3OH·2H2O (1), [Ni3L2(CH3OH)6(H2O)4][PW12O40]2·3CH3OH·2H2O (2) and [Ag3L(PMo12O40)] (3). In hybrids (1) and (2), Ni(ii) cations are linked by L ligands to produce layered frameworks, and H bonds among the [PMo12O40]3?/[PW12O40]3?anions and L ligands lengthen the structures to form 3D supramolecular architectures. Hybrid (3) exhibits a 3D architecture, of which Ag(i) cations not only coordinated with the N and O atoms of L ligands and [PMo12O40]3?anions simultaneously, but also connected each other by Ag-Ag interactions. It is worth mentioning that1and3as recyclable catalysts show excellent heterogeneous catalytic activity in oxidation desulfurization reactions.
- Li, Jie,Du, Peng,Liu, Ying-Ying,Ma, Jian-Fang
-
supporting information
p. 1349 - 1356
(2021/02/09)
-
- Air atmospheric photocatalytic oxidation by ultrathin C,N-TiO2nanosheets
-
Herein, we demonstrate the highly efficient photocatalytic sulfide oxidation reaction under mild conditions,i.e.in air, at room temperature and in the absence of a sacrificial reagent, co-catalyst or redox mediator, by using ultrathin C,N-TiO2nanosheets as a photocatalyst.
- Cheng, Xiuyan,Zhang, Jianling,Liu, Lifei,Zheng, Lirong,Zhang, Fanyu,Duan, Ran,Sha, Yufei,Su, Zhuizhui,Xie, Fei
-
supporting information
p. 1165 - 1170
(2021/02/26)
-
- Magneli-type tungsten oxide nanorods as catalysts for the selective oxidation of organic sulfides
-
Selective oxidation of thioethers is an important reaction to obtain sulfoxides as synthetic intermediates for applications in the chemical industry, medicinal chemistry and biology or the destruction of warfare agents. The reduced Magneli-type tungsten oxide WO3?xpossesses a unique oxidase-like activity which facilitates the oxidation of thioethers to the corresponding sulfoxides. More than 90% of the model system methylphenylsulfide could be converted to the sulfoxide with a selectivity of 98% at room temperature within 30 minutes, whereas oxidation to the corresponding sulfone was on a time scale of days. The concentration of the catalyst had a significant impact on the reaction rate. Reasonable catalytic effects were also observed for the selective oxidation of various organic sulfides with different substituents. The WO3?xnanocatalysts could be recycled at least 5 times without decrease in activity. We propose a metal oxide-catalyzed route based on the clean oxidant hydrogen peroxide. Compared to other molecular or enzyme catalysts the WO3?xsystem is a more robust redox-nanocatalyst, which is not susceptible to decomposition or denaturation under standard conditions. The unique oxidase-like activity of WO3?xcan be used for a wide range of applications in synthetic, environmental or medicinal chemistry.
- D?ren, René,Hartmann, Jens,Leibauer, Benjamin,Panth?fer, Martin,Mondeshki, Mihail,Tremel, Wolfgang
-
p. 14027 - 14037
(2021/10/19)
-
- Synergistic cooperative effect of CF3SO2Na and bis(2-butoxyethyl)ether towards selective oxygenation of sulfides with molecular oxygen under visible-light irradiation
-
A safe, practical and eco-friendly method for the switchable synthesis of sulfoxides and sulfones through visible-light-initiated oxygenation of sulfides at ambient temperature under transition-metal-, additives-free and minimal solvent conditions. The synergistic catalytic efforts between CF3SO2Na and 2-butoxyethyl ether represents the key promoting factor for the reaction. This journal is
- Liu, Kai-Jian,Wang, Zheng,Lu, Ling-Hui,Chen, Jin-Yang,Zeng, Fei,Lin, Ying-Wu,Cao, Zhong,Yu, Xianyong,He, Wei-Min
-
supporting information
p. 496 - 500
(2021/01/28)
-
- Electrochemical oxygenation of sulfides with molecular oxygen or water: Switchable preparation of sulfoxides and sulfones
-
A practical and eco-friendly method for the controllable aerobic oxygenation of sulfides by electrochemical catalysis was developed. The switchable preparation of sulfoxides and sulfones was effectively controlled by reaction time, in which both molecular oxygen and water can be used as the oxygen source under catalyst and external oxidant-free conditions. The electrochemical protocol features a broad substrate scope and excellent site selectivity and is successfully applied to the modification of some sulfide-containing pharmaceuticals and their derivatives. This journal is
- Li, Jin-Heng,Li, Yang,Sun, Qing,Xue, Qi,Zhang, Ting-Ting
-
supporting information
p. 10314 - 10318
(2021/12/17)
-
- Flow Electrosynthesis of Sulfoxides, Sulfones, and Sulfoximines without Supporting Electrolytes
-
An efficient electrochemical flow process for the selective oxidation of sulfides to sulfoxides and sulfones and of sulfoxides toN-cyanosulfoximines has been developed. In total, 69 examples of sulfoxides, sulfones, andN-cyanosulfoximines have been synthesized in good to excellent yields and with high current efficiencies. The synthesis was assisted and facilitated through a supporting electrolyte-free, fully automated electrochemical protocol that highlights the advantages of flow electrolysis.
- Amri, Nasser,Wirth, Thomas
-
p. 15961 - 15972
(2021/07/20)
-
- Electrochemical Scalable Sulfoxidation of Sulfides with Molecular Oxygen and Water
-
An efficient and chemoselective synthesis of sulfoxides through the electrooxidation of sulfides has been well developed. This protocol takes advantage of electricity as the terminal oxidant and of molecular oxygen and water as the oxygen atom sources. A variety of structurally diverse sulfoxide compounds are assembled in moderate to excellent yields. The scaled-up reactions at 6–20 mmol show the good practicability and application potential of this methodology. A possible free radical mechanism has been proposed to rationalize the reaction procedure.
- Cheng, Zhen,Gao, Xinglian,Yao, Lingling,Wei, Zhaoxin,Qin, Guohui,Zhang, Yonghong,Wang, Bin,Xia, Yu,Abdukader, Ablimit,Xue, Fei,Jin, Weiwei,Liu, Chenjiang
-
p. 3743 - 3747
(2021/07/26)
-
- Modulation of photochemical oxidation of thioethers to sulfoxides or sulfones using an aromatic ketone as the photocatalyst
-
We have developed an eco-friendly and chemo-selective photocatalytic synthesis of sulfoxides or sulfones via oxidation of sulfides (thioethers) at ambient temperature using air or O2 as the oxidant. An inexpensive thioxanthone was used as the photocatalyst. Our method offers excellent chemical yields and good functional group tolerance. The hydrogen bonding between hexafluoro-2-propanol (HFIP) and sulfoxides may play an important role in minimizing the over-oxidization of sulfoxides.
- Zhao, Bin,Hammond, Gerald B.,Xu, Bo
-
supporting information
(2021/09/13)
-
- Sulfoxide and Sulfone Synthesis via Electrochemical Oxidation of Sulfides
-
The oxidation of diaryl sulfides and aryl alkyl sulfides to the corresponding sulfoxides and sulfones under electrochemical conditions is reported. Sulfoxides are selectively obtained in good yield under a constant current of 5 mA for 10 h in DMF, while sulfones are formed as the major product under a constant current of 10 or 20 mA for 10 h in MeOH. The oxygen of both the sulfoxide and sulfone function is derived from water.
- Lee, Sunwoo,Park, Jin Kyu
-
p. 13790 - 13799
(2021/10/12)
-
- Tetrameric Lanthanide-Substituted Silicotungstate {Ln8Si4W40} Nanoclusters: Synthesis, Structural Characterization, Electrochemistry, and Catalytic Application for Oxidation of Thioethers
-
All the title nanoclusters 1–10 with the molecular formula [(Ln2SiW10O38)4(W3O8)(OH)4(H2O)2]26? [LnIII =Sm (1), Eu (2), Gd (3), Tb (4), Dy (5), Ho (6), Er (7), Tm (8), Yb (9), and Y (10)] have been synthesized and isolated as mixed sodium and potassium salts. These nanoclusters are characterized by various analytical techniques such as FT-IR, UV/Vis, Photoluminescence, Single crystal X-ray diffraction, Electrochemistry, ICP-AES and Thermogravimetric analysis, and Powder X-ray diffraction. The {Ln8Si4W40} complexes show high efficiency and selectivity for the oxidation of thioethers using H2O2 as green oxidant. It is worth mentioning that the catalyst can be recovered even after five cycles of reaction with only a slight loss in its activity.
- Khan, Imran,Das, Vivek,Teillout, Anne-Lucie,Mbomekallé, Isra?l-Martyr,de Oliveira, Pedro,Sahoo, Subash Chandra,Hussain, Firasat
-
supporting information
p. 1071 - 1081
(2021/03/16)
-
- A μ-AsO4-Bridging Hexadecanuclear Ni-Substituted Polyoxotungstate
-
A novel tetrahedral μ-AsO4-bridging hexadecanuclear Ni-substituted silicotungstate (ST) Na21H10[(AsO4){Ni8(OH)6(H2O)2(CO3)2(A-α-SiW9O34)2}2]·60H2O (1) was made by the reactions of trivacant [A-α-SiW9O34]10- ({SiW9}) units with Ni2+ cations and Na3AsO4·12H2O and characterized by IR spectrometry, elemental analysis, thermogravimetric analysis (TGA), and powder X-ray diffraction (PXRD). 1 contains a novel polyoxoanion [(AsO4){Ni8(OH)6(H2O)2(CO3)2(A-α-SiW9O34)2}2]31- built by four trivacant Keggin [A-α-SiW9O34]10- fragments linked through an unprecedented [(AsO4){Ni8(OH)6(H2O)2(CO3)2}2]9+ cluster, where the tetrahedral AsO4 acts as an exclusively μ2-bridging unit to link multiple Ni centers; such a connection mode appears for the first time in polyoxometalate chemistry. Furthermore, the electrochemical and catalytic oxidation properties of compound 1 have been investigated.
- Lian, Chen,Li, Hai-Lou,Yang, Guo-Yu
-
p. 3996 - 4003
(2021/04/07)
-
- COMPOSITES, METHODS AND USES THEREOF
-
The present invention relates, in general terms, to methods of catalysing a reaction, including the steps of contacting a chemical entity comprising a sulphide moiety with a composite and an oxidant. The composite acts as a heterogeneous catalyst to oxidise the sulphide moiety. The present invention also relates to composites, methods of synthesising the composites and its use as a catalyst thereof.
- -
-
Page/Page column 26
(2021/06/04)
-
- A {Ti6W4}-Cluster-Substituted Polyoxotungstate: Synthesis, Structure, and Catalytic Oxidation Properties
-
A novel Ti-W-O-cluster-substituted tungstoantimonate (TA), [H2N(CH3)2]3Na4H9[{Ti6W4O18(OH)(H2O)3}(B-α-SbW9O33)3]·20H2O (1), has been made by hydrothermal reactions of trivacant [B-α-SbW9O33]9- units, Ti4+ cations, and WO42- anions in the presence of [H2N(CH3)2]·Cl and structurally characterized. Intriguingly, the polyoxoanion of 1 is constructed from three [B-α-SbW9O33]9- units and a previously unobserved decanuclear heterometallic Ti-W-O cluster [Ti6W4O18(OH)(H2O)3]11+ ({Ti6W4}) that is comprised of an octahedral [Ti6WO6(H2O)3]18+ cluster and an edge-sharing [W3O12(OH)]7- fragment via six W-O-Ti/W linkers. Furthermore, studies on the catalytic oxidation properties reveal that 1 possesses good catalytic activity toward the oxidation reactions of various sulfides and cyclooctene based on the environmentally friendly oxidant H2O2.
- Li, Hai-Lou,Lian, Chen,Yang, Guo-Yu
-
supporting information
p. 14622 - 14628
(2021/10/01)
-
- Single-Molecule Magnetic, Catalytic and Photoluminescence Properties of Heterometallic 3d–4f [Ln{PZn2W10O38(H2O)2}2]11? Tungstophosphate Nanoclusters
-
A series of eleven lanthanide containing di-Zinc (II) substituted heterometallic 3d–4f sandwich-type tungstophosphate nanoclusters [Ln{PZn2W10O38(H2O)2}2]11? (Ln=NdIII, SmIII, EuIII, GdIII, TbIII, DyIII, HoIII, ErIII, TmIII, YbIII, and LuIII) have been synthesized by a single step reaction procedure. These clusters were characterized by various analytical techniques such as single crystal X-ray diffraction (SC-XRD), fourier transform infrared (FT-IR) spectroscopy, high-resolution electro-spray ionization mass spectrometry (HR-ESI-MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), solid UV/Vis, photoluminescence spectroscopy, powder X-ray diffraction (P-XRD) and thermogravimetric analysis (TGA). All the polyanions are isostructural and consists of a lanthanide ion sandwiched between two units of (1,5) isomer of di-Zn substituted α-Keggin type tungstophosphate. The complexes Sm-2 a, Eu-3 a, Tb-5 a, and Dy-6 a show good photoluminescence behavior. The catalytic properties were examined for the oxidation of thioethers. The catalyst is stable with a high turn over frequency (TOF) of 6250 h?1 and can be recovered even after 5 consecutive cycles. Furthermore, magnetic properties revealed that Gd-4 a, Tb-5 a, Dy-6 a, Er-8 a, and Yb-10 a show single-molecule magnetic properties.
- Das, Vivek,Khan, Imran,Hussain, Firasat,Sadakane, Masahiro,Tsunoji, Nao,Ichihashi, Katsuya,Kato, Chisato,Inoue, Katsuya,Nishihara, Sadafumi
-
p. 3819 - 3831
(2021/09/22)
-
- Highly efficient and selective aqueous aerobic oxidation of sulfides to sulfoxides or sulfones catalyzed by tungstate-functionalized nanomaterial
-
A Br?nsted acidic ionic solid comrising tungstate-functionaized polyorganosiloxane framework (PMO-IL-WO42?) efficiently catalysed aerobic oxidation of sulfides in aqueous medium. The catalyst can selectively produce sulfoxides or sulfones by running the reaction at room temperature or 50 °C, respectively. Because of the ionic liquid-based charged surface containing hydrophobic organic functional groups and hydrophilic sulfonic acid group, the synergestic hydrophobic/hydrophilic and redox effect of PMO-IL-WO42- as water-friendly interfacial nanocatalyst simplifies and enhances the activity and selectivity toward the target sulfoxides or sulfones in water. Moreover, the PMO-IL-WO42- nanocatalyst exhibited outstanding stability and activity and can be recycled eight reaction runs without any significant activity and selectivity loss.
- Luque, Rafael,Rajabi, Fatemeh,Vessally, Esmail,Voskressensky, Leonid
-
-
- {Ti6}/{Ti10} Wheel Cluster Substituted Silicotungstate Aggregates
-
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 a Ti6O6 ({Ti6}) wheel cluster is encapsulated by three divacant [SiW10O37]10- (SiW10O37) fragments. However, 2 is built by two divacant SiW10O37 units and two rare trivacant [SiW9O35]12- (SiW9O35) fragments and further installs an unprecedented Ti10O11 ({Ti10}) double-wheel cluster. To the best of our knowledge, 2 is rare in POM chemistry. Studies on the catalytic oxidation properties reveal that 1 exhibits high catalytic activity toward the oxidation of various sulfides using H2O2 as an oxidant. Furthermore, 1 can be facilely recycled and reused for at least five cycles without obvious loss of catalytic activity.
- Li, Hai-Lou,Lian, Chen,Yang, Guo-Yu
-
p. 16852 - 16859
(2021/11/13)
-
- Niobium(V) oxido tris-carbamate as easily available and robust catalytic precursor for the selective sulfide to sulfone oxidation
-
The oxidation of the sulfide function promoted by a variety of vanadium compounds has been largely explored, whereas the use of homogeneous catalytic systems based on the heavier group 5 metals remains less explored. We report the use of easily available niobium and tantalum carbamates, i.e. [M(O2CNMe2)5] (M = Nb, 1; M = Ta, 2), [Nb(O2CNMe2)4], 3, [NbO(O2CNEt2)3], 4, and [NbCl3(O2CNEt2)2], 5, as effective catalysts for the conversion of a series of alkyl aryl and aromatic sulfides into the corresponding sulfones. NMR investigations on the performant niobium catalyst 4 unexpectedly revealed the substantial stability of this compound in the protic catalytic environment, and a plausible catalytic cycle was obtained by DFT studies. The two active catalytic species, i.e. 4 and its minor mono-methoxide derivative, presumably interconvert to each other exploiting the versatile coordination of the carbamato ligand.
- Bresciani, Giulio,Ciancaleoni, Gianluca,Crucianelli, Marcello,Gemmiti, Mario,Marchetti, Fabio,Pampaloni, Guido
-
-
- Method for synthesizing aryl alkyl sulfone compound by promoting oxidation of aryl alkyl thioether compound through visible light
-
The invention discloses a method for synthesizing an aryl alkyl sulfone compound by promoting oxidation of an aryl alkyl thioether compound through visible light. The method comprises the following steps of: performing one-pot reaction on an aryl alkyl thioether compound and sodium trifluoromethanesulfinate in a diethylene glycol dibutyl ether solution system under the conditions of oxygen-containing atmosphere and 385-390 nm purple light irradiation to generate the aryl alkyl sulfone compound. The method has the advantages of mild conditions, simple operation, environmental protection, easilyavailable raw materials, excellent compatibility of substrate functional groups, high reaction yield and the like.
- -
-
Paragraph 0049-0052; 0057-0064
(2021/02/13)
-
- Copper-Catalyzed Methoxylation of Aryl Bromides with 9-BBN-OMe
-
A Cu-catalyzed cross-coupling reaction between aryl bromides and 9-BBN-OMe to provide aryl methyl ethers under mild conditions is reported. The oxalamide ligand BHMPO plays a key role in the transformation. Various functional groups on bromobenzenes are well tolerated, providing the desired anisole products in moderate to high yields.
- Li, Chen,Song, Zhi-Qiang,Wang, Dong-Hui,Wang, Jing-Ru
-
supporting information
p. 8450 - 8454
(2021/11/17)
-
- Primary Sulfonamide Functionalization via Sulfonyl Pyrroles: Seeing the N?Ts Bond in a Different Light
-
Despite common occurrence in molecules of value, methods for transforming sulfonamides are distinctly lacking. Here we introduce easy-to-access sulfonyl pyrroles as synthetic linchpins for sulfonamide functionalization. The versatility of the sulfonyl pyrrole unit is shown by generating a variety of products through chemical, electrochemical and photochemical pathways. Preliminary results on the direct functionalization of primary sulfonamides are also provided, which may lead to new modes of activation.
- Ozaki, Tomoya,Yorimitsu, Hideki,Perry, Gregory J. P.
-
p. 15387 - 15391
(2021/10/04)
-
- Preparation method of methyl sulfone compound
-
The invention discloses a synthesis method of a methyl sulfone compound, which comprises the following steps: by using an iodinated compound as a substrate, adding a sulfite compound into the substrate, and using a 1, 4-dioxane solution as a solvent, heating under the protection of nitrogen under the actions of a silicon reagent, a phase transfer catalyst and a palladium catalyst to obtain a crudeproduct; then purifying the crude product, firstly filtering the crude product, and removing the solvent to obtain residues; carrying out silica gel column chromatography on the residues, leaching with eluent, and collecting effluent; combining the effluent containing the product; and concentrating the combined effluent to remove the solvent, and finally carrying out vacuum drying to obtain the target product. The method has the advantages of simple process flow, easiness in product purification, environmental safety and high yield.
- -
-
Paragraph 0005; 0017
(2021/02/24)
-
- A highly stable all-in-one photocatalyst for aryl etherification: The NiIIembedded covalent organic framework
-
The efficient conversion of aryl bromides to the corresponding aryl alkyl ethers by dual nickel/photocatalysis has seen great progress, but difficulties of recycling the photosensitizer or nickel complexes cause problems of sustainability. Here, we report the design of a novel, highly stable vinyl bridge 2D covalent organic framework (COF) containing Ni, which combines the role of photosensitizer and reactive site. The as-prepared sp2c-COFdpy-Ni acts as an efficient heterogeneous photocatalyst for C-O cross coupling. The sp2c-COFdpy-Ni can be completely recovered and used repeatedly without loss of activity, overcoming the limitations of the prior methods. Preliminary studies reveal that strong interlayer electron transfer may facilitate the generation of the proposed intermediate sp2c-COFdpy-NiI in a bimolecular and self-sustained manner. This all-in-one heterogeneous photocatalyst exhibits good compatibility of substrates and tolerance of functional groups. The successful attempt to expand the 2D COFs with this new catalyst into photocatalytic organic transformation opens an avenue for photoredox/transition metal mediated coupling reactions.
- Chen, Hao,Dong, Wenbo,Hu, Jianxiang,Rao, Li,Wang, Pei,Wang, Shengyao,Xiang, Yonggang,Yang, Yi
-
p. 5797 - 5805
(2021/08/23)
-
- Visible-Light Promoted C–O Bond Formation with an Integrated Carbon Nitride–Nickel Heterogeneous Photocatalyst
-
Ni-deposited mesoporous graphitic carbon nitride (Ni-mpg-CNx) is introduced as an inexpensive, robust, easily synthesizable and recyclable material that functions as an integrated dual photocatalytic system. This material overcomes the need of expensive photosensitizers, organic ligands and additives as well as limitations of catalyst deactivation in the existing photo/Ni dual catalytic cross-coupling reactions. The dual catalytic Ni-mpg-CNx is demonstrated for C–O coupling between aryl halides and aliphatic alcohols under mild condition. The reaction affords the ether product in good-to-excellent yields (60–92 %) with broad substrate scope, including heteroaryl and aryl halides bearing electron-withdrawing, -donating and neutral groups. The heterogeneous Ni-mpg-CNx can be easily recovered from the reaction mixture and reused over multiple cycles without loss of activity. The findings highlight exciting opportunities for dual catalysis promoted by a fully heterogeneous system.
- Vijeta, Arjun,Casadevall, Carla,Roy, Souvik,Reisner, Erwin
-
supporting information
p. 8494 - 8499
(2021/03/08)
-
- Two polyoxometalate-based inorganic-organic hybrids and one coordination polymer assembled with a functionalized calix[4]arene: Catalytic and electrochemical properties
-
Self-assembly of 4-pyridyl-functionalized calix[4]arene ligand 5,11,17,23-tetrakis(1,1-dimethylethyl)-25,26,27,28-tetrakis[(4-pyridylmethyl)oxy]calix[4]arene (L), Ag(I)/Cd(II) cations and polyoxometalate obtained two inorganic-organic hybrids [Ag3(L)2][PMo12O40]·CH3CN·4H2O (1), [Ag3(L)2][PMo12O40]·2DMA·0.5EtOH (2) and one complex [Cd3(L)2Cl6]·4CH3CN·4H2O (3) (DMA = N,N-dimethylacetamide). Hybrids 1 and 2 have fascinating one-dimensional chains, which are linked by hydrogen bonds between the C atoms of L ligands and the O atoms of [PMo12O40]3? anions to generate supramolecular layers. 3 displays a thick layer containing trinuclear Cd(II) clusters. Noteworthy, hybrid 1 exhibits excellent heterogeneous catalytic activity for oxidative desulfurization reaction and obvious electrocatalytic activity for oxidize ascorbic acid and reduce NaBrO3. Complex 3 shows heterogeneous catalytic ability for Knoevenagel condensation reaction.
- Li, Zhuo,Liu, Ying-Ying,Xu, Guo-Hai,Ma, Jian-Fang
-
-
- Formation and kinetic studies of manganese(IV)-oxo porphyrins: Oxygen atom transfer mechanism of sulfide oxidations
-
Visible light irradiation of photo-labile porphyrin-manganese(III) chlorates or bromates (2) produced manganese(IV)-oxo porphyrins [MnIV(Por)(O)] (Por = porphyrin) (3) in three porphyrin ligands. The same oxo species 3 were also formed by chemical oxidation of the corresponding manganese(III) precursors (1) with iodobenzene diacetate, i.e. PhI(OAc)2. The systems under study include 5,10,15,20-tetra(pentafluorophenyl)porphyrin?manganese(IV)-oxo (3a), 5,10,15,20-tetra(2,6-difluorophenyl)porphyrin?manganese(IV)-oxo (3b), and 5,10,15,20-tetramesitylporphyrin?manganese(IV)-oxo (3c). As expected, complexes 3 reacted with thioanisoles to produce the corresponding sulfoxides and over-oxidized sulfones. The kinetics of oxygen atom transfer (OAT) reactions of these generated 3 with aryl sulfides were studied in CH3CN solutions. Second-order rate constants for sulfide oxidation reactions are comparable to those of alkene epoxidations and activated C[sbnd]H bond oxidations by the same oxo species 3. For a given substrate, the reactivity order for the manganese(IV)-oxo species was 3a > 3b > 3c, consistent with expectations on the basis of the electron-withdrawing capacity of the porphyrin macrocycles. Free-energy Hammett analyses gave near-linear correlations with σ values, indicating no significant positive charge developed at the sulfur during the oxidation process. The mechanistic results strongly suggest [MnIV(Por)(O)] reacts as a direct OAT agent towards sulfide substrates through a manganese(II) intermediate that was detected in this work. However, an alternative pathway that involves a disproportionation of 3 to form a higher oxidized manganese(V)-oxo species may be significant when less reactive substrates are present. The competition product studies with the Hammett correlation plot confirmed that the observed manganese(IV)-oxo species is not the true oxidant for the sulfide oxidations catalyzed by manganese(III) porphyrins with PhI(OAc)2.
- Klaine, Seth,Bratcher, Fox,Winchester, Charles M.,Zhang, Rui
-
-
- Visible light generation of chromium(V)-oxo salen complexes and mechanistic insights into catalytic sulfide oxidation
-
Visible light irradiation of the photo-labile salen-chromium(III) chlorate or bromate precursors produced salen-chromium(V)-oxo complexes that were spectroscopically and kinetically indistinguishable from those formed by chemical oxidation of chromium(III) salens with PhI(OAc)2. The photochemistry observed in this work is ascribed to the heterolytic cleavage of the O-X bond in the apical counterion that results in a two-electron oxidation of the metal to form the chromium(V)-oxo species. Second-order rate constants for oxidation reactions of 3 with organic substrates were determined under pseudo-first order condition, and particularly low level of reactivity for sulfide oxidations was observed. In this study, chromium(III) salen complexes effectively catalyzed the oxidation of aryl sulfides into sulfoxides with PhI(OAc)2 in the presence of a small amount of water. The competition product studies with the Hammett correlation plot indicated that the observed chromium(V)-oxo species is not likely to serve as the major oxidant for the sulfide oxidations catalyzed by chromium(III) salens with PhI(OAc)2.
- Dames, Angeline,Fung Lee, Ngo,Klaine, Seth,Zhang, Rui
-
-
- Efficient Catalytic Oxidative Desulfurization toward Thioether and Sulfur Mustard Stimulant by Polyoxomolybdate-Resorcin[4]arene-Based Metal-Organic Materials
-
The design and synthesis of effective and recyclable oxidative desulfurization catalysts is of great importance in view of environmental protection and human health. Herein, a family of polyoxomolybdate-based inorganic-organic hybrid materials, namely, [Mn(TMR4A)(H2O)4][Mo6O19]·0.5CH3CH2OH·H2O (1), [Ni(TMR4A)(H2O)4][Mo6O19]·0.5CH3CH2OH·H2O (2), [Zn(TMR4A)(H2O)4][Mo6O19]·0.5CH3CH2OH·H2O (3), and [Co2(TMR4A)2(H2O)4(β-Mo8O26)]·CH3CN·12H2O (4), were assembled by the functionalized resorcin[4]arene ligand (TMR4A) with polyoxomolybdate and metal ions under solvothermal conditions. In isostructural 1-3, the [M(TMR4A)(H2O)4]2+ species (M = MnII, NiII, ZnII) and [Mo6O19]2- anions are held together via C-H···O hydrogen bonds to give a 3D supramolecular architecture. In 4, two [Co(TMR4A)(H2O)2]2+ cations were linked by one [β-Mo8O26]4- anion to produce an attractive molecular dimer. Remarkably, 1-4, as recyclable heterogeneous catalysts, exhibit efficient catalytic oxidation desulfurization activities toward thioethers. Particularly, 1, as a representative example, features selective catalytic oxidation for sulfur mustard simulant. Moreover, their electrochemical properties were also studied.
- Guo, Ting-Ting,Ma, Jian-Fang,Yang, Jin,Yu, Ming-Yue
-
supporting information
(2020/04/02)
-
- Synthesis method of sulfone compound
-
The invention discloses a synthesis method of a sulfone compound. The synthesis method specifically comprises the following steps: taking a compound shown as formula (I) as a reaction raw material, Ru/C as a catalyst, NaIO4 as an oxidant and water as a solvent, reacting at room temperature, and after the reaction is finished, carrying out after-treatment on an obtained reaction solution to obtainthe sulfone compound shown as formula (II), wherein the use amount of Ru/C is 0.5-2% of the molar amount of the compound shown in the formula (I) in terms of the molar amount of Ru; the molar amount of NaIO4 is 50-150% of the molar amount of the compound represented by formula (I). Under normal temperature conditions, cheap ruthenium carbon is oxidized by sodium periodate to generate ruthenium tetroxide, so that a thioether compound is further oxidized to synthesize the sulfone compound, the yield is close to 100 %, the subsequent treatment is simple, and a pure product can be obtained withoutcomplex separation and purification. Therefore, the method is more efficient, faster, more environmentally friendly and milder.
- -
-
Paragraph 0055-0059
(2020/01/25)
-
- Copper(ii)-containing tungstotellurates(vi): Syntheses, structures and their catalytic performances in selective oxidation of thioethers
-
We report the syntheses and structures of two new copper(ii)-containing tungstotellurates(vi) Na12[TeVI2W8O38Cu2(H2O)2]·7H2O (Te2W8Cu2) and Na6[TeVIW6O24Cu(NH2CH2CO2)2]·6H2O (TeW6Cu). The two compounds were synthesized by a simple one-pot method and characterized by single-crystal X-ray diffraction (XRD), powder XRD, FT-IR spectroscopy, elemental analysis, and thermogravimetric analysis in the solid state. Furthermore, their catalytic properties for the selective oxidation of thioethers were also studied systematically. The catalytic experiment results indicate that the tungstotellurate(vi) Te2W8Cu2 is an effective heterogeneous catalyst for the selective oxidation of thioethers to sulfoxides or sulfones by an H2O2 oxidant at room temperature. Under the ambient conditions, Te2W8Cu2 can convert 99percent of methyl(phenyl)sulfane to sulfoxides or sulfones with 96percent or 99percent selectivity, respectively, and the utilization rate of H2O2 is up to 80percent. Furthermore, Te2W8Cu2 as a heterogeneous catalyst is stable in the reaction and could be reused at least five cycles with conserved activity.
- Hu, Changwen,Li, Peihe,Li, Xuanyao,Lin, Zhengguo,Liu, Jinghai
-
p. 22515 - 22521
(2020/07/03)
-
- Selective oxidation of (hetero)sulfides with molecular oxygen under clean conditions
-
The development of eco-friendly and switchable catalytic systems for the conversion of a sole raw-material into distinct high-value products is a particularly attractive concept and a daunting synthetic challenge. In the present work, the first example of efficient and selective oxidation of sulfides to sulfones and sulfoxides using molecular oxygen under clean conditions was established.
- Liu, Kai-Jian,Deng, Ji-Hui,Yang, Jie,Gong, Shao-Feng,Lin, Ying-Wu,He, Jun-Yi,Cao, Zhong,He, Wei-Min
-
supporting information
p. 433 - 438
(2020/02/13)
-
- Oxidation of aromatic sulfides with molecular oxygen: Controllable synthesis of sulfoxides or sulfones
-
The recent development of selective oxidation of aromatic sulfides with molecular oxygen was highlighted. The sulfoxides and sulfones could be obtained by simply switching the reaction media, i.e., bis(2-butoxyethyl)ether (BBE) or poly(ethylene glycol)dimethyl ether (PEGDME). The application of the high-boiling-point polyether as an initiator and green media can eliminate the need of large quantities of additives and volatile solvents. This strategy represents an economic and eco-friendly method that could find potential applications.
- Tang, Lili,Du, Kejie,Yu, Bing,He, Liangnian
-
p. 2991 - 2992
(2020/03/24)
-
- Three Zr(IV)-Substituted Polyoxotungstate Aggregates: Structural Transformation from Tungstoantimonate to Tungstophosphate Induced by pH
-
Three novel Zr-substituted polyoxotungstate aggregates [H2N(CH3)2]7NaH2[Zr2Sb2O3(A-α-PW9O34)2]·16H2O (1), [H2N(CH3)2]6H12[ZrSb4(OH)O2(A-α-PW8O32)(A-α-PW9O34)]2·33H2O (2), and [H2N(CH3)2]4Na11.5H4.5[Zr4W8Sb4P5O49(OH)5(B-α-SbW9O33)2]·53H2O (3) have been made in hydrothermal reactions of the [B-α-SbW9O33]9- precursor with Zr4+ cations and PO43- anions in the presence of dimethylamine hydrochloride and sodium acetate buffer (pH = 4.8) and structurally characterized. Different pH values induce structural transformation from tungstoantimonate (TA) to tungstophosphate (TP). 1 is a di-Zr-substituted sandwich-type TP, the tetranuclear heterometallic [Zr2Sb2O3]8+ entity sandwiched by two [A-α-PW9O34]9- moieties. 2 is a double sandwich-type structure, which can be perceived as two equivalent sandwiched [Sb3(PW8O32)(PW9O34)]11- further sandwiching one [Sb2Zr2(OH)2O4]4+ core to form a novel large-size sandwich-type architecture. Different from 1 and 2, 3 is a tetra-Zr-substituted sandwiched configuration, in which two [B-α-SbW9O33]9- fragments sandwich a unique 21-core Sb-P-W-Zr oxo cluster ({Zr4W8Sb4P5}). Furthermore, the catalytic oxidation of aromatic thioethers by 3 as the heterogeneous catalyst has been investigated, showing high conversion and remarkable selectivity as well as excellent recyclability.
- Li, Hai-Lou,Lian, Chen,Yang, Guo-Yu,Yin, Da-Peng
-
p. 12842 - 12849
(2020/09/15)
-
- Synthesis of Na22[((RE)4(H2O)6Sb6O4)(SbW10O37)2(SbW8O31)2] [(RE)III = Y, Gd, Tb, Dy, Ho, Er, Tm, Yb]: Synthesis, characterization and catalytic application
-
A series of eight rare-earth substituted antimony tungstates with the formulae [((RE)4(H2O)6Sb6O4)(SbW10O37)2(SbW8O31)2]22– [(RE)III = Y(1), Gd(2), Tb(3), Dy(4), Ho(5), Er(6), Tm(7), Yb(8)] has been synthesized under ambient conditions. The compounds were isolated using rare-earth salts and Na9[B-α-SbW9O33]?19.5 H2O as precursors along with sodium dihydrogen phosphate in 1 M NaCl solution. The addition of dihydrogen phosphate was found to be a crucial step for the isolation of these polyanions. The polyanions were characterized by various analytical techniques such as single crystal X-ray diffraction (1a – 6a) (SC-XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA). The compounds were found to show efficient heterogeneous catalytic activity for oxidation of thioethers.
- Gupta, Rakesh,Hussain, Firasat,Kaushik, Reetam,Khan, Imran
-
-
- Inorganic-organic hybrid polyoxovanadates based on [V4O12]4-or [VO3]22-clusters: Controllable synthesis, crystal structures and catalytic properties in selective oxidation of sulfides
-
By rationally controlling hydrothermal conditions, three new inorganic-organic hybrid polyoxovanadates (POVs) [Ni2(1-vIM)7H2O][V4O12]·H2O (1), [Cu2(1-vIM)8][V4O12]·H2O (2) and [Co(1-vIM)H2O][VO3]2 (3) (1-vIM = 1-vinylimidazole) have been synthesized and thoroughly characterized by single X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR), and elemental analyses (EA). Interestingly, complexes 1 and 2 have similar structures including [V4O12]4- clusters; complex 3, however, was isolated as a structure by including the [VO3]22- cluster under a different synthetic condition compared with those of 1 and 2. Both complexes 1 and 2 display an interesting 3D supramolecular structure, and complex 3 shows a 2D two parallel networks supramolecular structure linked by a [Co2O2] unit due to the different coordination environments of the central metals. Three inorganic-organic hybrid POVs asheterogeneous catalysts are active in the selective oxidation of sulfides to produce sulfoxides or sulfones with high conversion and high selectivity (up to 99.5 for sulfoxides and 98.5% for sulfones respectively catalyzed by 1). Complex 1 is also used as catalyst in the oxidative CEES (2-chloroethyl ethyl sulfide, a sulfur mustard simulant) abatement with high activity and selectivity towardthe corresponding sulfoxide. Moreover, complex 1 can be reused at least three times in sulfoxidationreactions without losing its activity.
- Guo, Daigaojie,Han, Yinfeng,He, Guofang,Hu, Changwen,Huang, Xianqiang,Li, Jikun,Wang, Congcong,Wei, Chuanping,Zhang, Jianping
-
p. 14148 - 14157
(2020/11/02)
-
- General sulfone construction: Via sulfur dioxide surrogate control
-
A highly efficient one-step synthesis of alkyl-alkyl and aryl-alkyl sulfones with a facile combination of halides, sulfur dioxide surrogates and phosphate esters is described. When thiourea dioxide was employed as a reductive sulfur dioxide surrogate, alkyl-alkyl sulfones were obtained under transition metal free conditions. Aryl-alkyl sulfones were obtained with an extremely low catalytic loading (0.2 mol%) via altering the mask of sulfur dioxide surrogates to sodium dithionite. A phosphate ester was employed as a stable and readily available alkyl source. Notably, this protocol has been applied to the late-stage modification of natural products and bioactive molecules.
- Chen, Shihao,Li, Yaping,Wang, Ming,Jiang, Xuefeng
-
supporting information
p. 322 - 326
(2020/02/13)
-
- General Paradigm in Photoredox Nickel-Catalyzed Cross-Coupling Allows for Light-Free Access to Reactivity
-
Self-sustained NiI/III cycles are established as a potentially general paradigm in photoredox Ni-catalyzed carbon–heteroatom cross-coupling reactions through a strategy that allows us to recapitulate photoredox-like reactivity in the absence of light across a wide range of substrates in the amination, etherification, and esterification of aryl bromides, the latter of which has remained, hitherto, elusive under thermal Ni catalysis. Moreover, the accessibility of esterification in the absence of light is especially notable because previous mechanistic studies on this transformation under photoredox conditions have unanimously invoked energy-transfer-mediated pathways.
- Nocera, Daniel G.,Qin, Yangzhong,Sun, Rui
-
supporting information
p. 9527 - 9533
(2020/04/08)
-
- HETEROCYCLIC CARBOXYLIC ACID AMIDE LIGAND AND APPLICATIONS THEREOF IN COPPER CATALYZED COUPLING REACTION OF ARYL HALOGENO SUBSTITUTE
-
Provided are a heterocyclic carboxylic acid amide ligand and applications thereof in a copper catalyzed coupling reaction. Specifically, provided are uses of a compound represented by formula (I), definitions of radical groups being described in the specifications. The compound represented by formula (I) can be used as the ligand in the copper catalyzed coupling reaction of the aryl halogeno substitute, and is used or catalyzing the coupling reaction for forming the aryl halogeno substitute having C—N, C—O, C—S and other bonds.
- -
-
Paragraph 0293-0294
(2019/05/15)
-
- A New Hepta-Nuclear Ti-Oxo-Cluster-Substituted Tungstoantimonate and Its Catalytic Oxidation of Thioethers
-
A neoteric hepta-nuclear Ti-oxo-cluster-substituted tetrameric tungstoantimonate [H2N(CH3)2]22Na18{Ti7O6(SbW9O33)4}2·124H2O (1) has hydrothermally been synthesized and tested by single-crystal/powder X-ray diffraction, IR spectra, and thermal analysis. The glamorous feature of this tetrameric polyoxoanion is an uncommon hepta-nuclear Ti-oxo-cluster octahedron [Ti7O6]16+ enclosed in four [B-α-SbW9O33]9- building units. As a heterogeneous catalyst, the investigation on catalytic oxidation with H2O2 for multiple thioethers indicated that 1 possesses high conversion and remarkable selectivity. Additionally, 1 exhibits good stability and excellent recyclability.
- Li, Hai-Lou,Lian, Chen,Yin, Da-Peng,Jia, Zhi-Yu,Yang, Guo-Yu
-
p. 376 - 380
(2019/01/09)
-
- Ionic Liquid Stabilized Niobium Oxoclusters Catalyzing Oxidation of Sulfides with Exceptional Activity
-
We present here a new class of niobium oxoclusters that are stabilized effectively by carboxylate ionic liquids. These functionalized ILs are designated as [TBA][LA], [TBA][PA], and [TBA][HPA] in this work, in which TBA represents tetrabutylammonium and LA, PA, and HPA refer to lactate, propionate, 3-hydroxypropionate anions, respectively. The as-synthesized Nb oxoclusters have been characterized by use of elemental analysis, NMR, IR, XRD, TGA, HRTEM. It was found that [TBA][LA]-stabilized Nb oxoclusters (Nb?OC@[TBA][LA]) are uniformly dispersed with an average particle size of 2–3 nm and afforded exceptionally high catalytic activity for the selective oxidation of various thioethers. The turnover number with Nb?OC@[TBA][LA] catalyst was over 56 000 at catalyst loading as low as 0.0033 mol % (1 ppm). Meantime, the catalyst also showed the high activity for the epoxidation of olefins and allylic alcohols by using only 0.065 mol % of catalyst (50 ppm). The characterization of 93Nb NMR spectra revealed that the Nb oxoclusters underwent structural transformation in the presence of H2O2 but regenerated to their initial state at the end of the reaction. In particular, the highly dispersed Nb oxoclusters can absorb a large amount of polar organic solvents and thus were swollen greatly, which exhibited “pseudo” liquid phase behavior, and enabled the substrate molecules to be highly accessible to the catalytic center of Nb oxocluster units.
- Zhou, Qingqing,Ye, Man,Ma, Wenbao,Li, Difan,Ding, Bingjie,Chen, Manyu,Yao, Yefeng,Gong, Xueqing,Hou, Zhenshan
-
p. 4206 - 4217
(2019/03/26)
-
- Selective catalytic oxidation of sulfides to sulfoxides or sulfones over amorphous Nb2O5/AC catalysts in aqueous phase at room temperature
-
Selective oxidation of sulfides into sulfoxides or sulfones is an important transformation in organic synthesis. Activated carbon supported Nb-based catalysts were prepared by the impregnation method and then characterized by the XRD, TEM and XPS. The characterization results indicate Nb species is amorphous Nb2O5. The catalysts were applied for the catalytic oxidation of sulfides in aqueous phase with H2O2 as the oxidant. Sulfides could be converted into the corresponding sulfoxides or sulfones with high conversion and selectivity at room temperature. The recycling experiments showed the Nb2O5/AC catalysts exhibited good reusability. They could be recycled for 10 times without obvious loss of activity and selectivity.
- Zhang, Junjie,Jiang, Tingting,Mai, Yuliang,Wang, Xi,Chen, Jiazhi,Liao, Bing
-
-
- Highly stable polyoxometalate-resorcin[4]arene-based inorganic-organic complexes for catalytic oxidation desulfurization
-
Self-assembly of a resorcin[4]arene-based ligand (TMR4A) with metal salts and H3PMo12O40·xH2O offers two isostructural complexes, namely, [Ni2Cl(TMR4A)2(CH3CN)2]·[PMo12O40]·4CH3CN (1) and [Co2Cl(TMR4A)2(CH3CN)2]·[PMo12O40]·4CH3CN (2). In both 1 and 2, one Cl? anion bridges two metal cations, and each metal cation is further chelated by four 2-mercaptopyridine N-oxide groups of one TMR4A, producing a [M2Cl(TMR4A)2]3+ dimer (M?=?Ni or Co). The negative [PMo12O40]3? as a counter-anion balances the positive charge. Markedly, 1 and 2 exhibit high stability in aqueous solutions with different pH values and in organic solvents. Remarkably, the efficient heterogeneous catalytic capability for oxidative desulfurization was studied by suing 1 and 2 as recycled catalysts. Moreover, the electrochemical behaviors of the two compounds were discussed as well.
- Yu, Ming-Yue,Yang, Jin,Xu, Xianxiu,Ma, Jian-Fang,Wang, Zhenxing
-
-
- Polyoxometalate-Bridged Cu(I)- And Ag(I)-Thiacalix[4]arene Dimers for Heterogeneous Catalytic Oxidative Desulfurization and Azide-Alkyne "click" Reaction
-
Two remarkable polyoxometalate-bridged Cu(I)- and Ag(I)-thiacalix[4]arene dimers, namely, [Cu4(SiW12O40)(L)2(DMF)2]·2EtOH·DMF (1-Cu) and [Ag4(PMo12O40)(L)2]·OH (1-Ag), were prepared by using a new thiacalix[4]arene, metal cation and polyoxometalate (L = tetra[2-(ethylthio)-1-methyl-1H-imidazole]-thiacalix[4]arene). In 1-Cu and 1-Ag, two thiacalix[4]arenes were linked together by one [SiW12O40]4- or [PMo12O40]3- anion via two metal cations to give a molecular dimer. Further, adjacent dimers were extended into a high-dimensional supramolecular architecture through hydrogen bonds. Markedly, these molecular dimers are exceedingly stable in organic solvents and then were employed as efficient catalysts for catalytic oxidation desulfurization as well as the azide-alkyne "click" reaction.
- Yu, Ming-Yue,Guo, Ting-Ting,Shi, Xiao-Chuan,Yang, Jin,Xu, Xianxiu,Ma, Jian-Fang,Yu, Zhen-Tao
-
p. 11010 - 11019
(2019/08/26)
-
- Discovery of a New Family of Polyoxometalate-Based Hybrids with Improved Catalytic Performances for Selective Sulfoxidation: The Synergy between Classic Heptamolybdate Anions and Complex Cations
-
A series of functional cation-regulated isopolymolybdate-based organic-inorganic hybrid compounds, Na2H2[Mo4O12(C8H17O5N)2]·10H2O (1), Na2[M(Bis-tris)(H2O)]2[Mo7O24]·10H2O [M = Cu, 2; Ni, 3; Co, 4; Zn, 5; Bis-tris = 2,2-Bis(hydroxymethyl)-2,2′,2″-nitrilotriethanol], and (NH4)2[M(Bis-tris)(H2O)]2[Mo7O24]·6H2O (M = Zn, 6; Cu, 7), were synthesized and characterized toward advanced molecular catalyst design. Compound 1 is a covalently bonded adduct, and its self-assembly process can be probed by electrospray ionization mass spectrometry (ESI-MS). Compounds 2-7 are polyoxometalate (POM)-based hybrids containing classic heptamolybdate anions and complex cations with Bis-tris ligands. All of these compounds showed remarkable catalytic effects for selective sulfide oxidation. To the best of our knowledge, compound 5 presents the best catalytic activity so far among the reported hybrid materials with common easily synthesized small-molecule POM clusters and also exhibits outstanding reliability. The conclusion of the catalytic effect is drawn from the results that Zn-based compounds have better catalytic effects than other transition-metal-containing compounds and the compound constructed by Na+ has higher catalytic activity than that constructed by NH4 +. The mechanism studies show that the improvements of the catalytic performance are caused by the synergy between classic heptamolybdate anions and complex cations. ESI-MS data and UV-vis spectra revealed that the POM anions can form intermediate peroxomolybdenum units during catalytic reaction. Further, the combination of the substrate thioanisole with complex cations was characterized by NMR experiments and UV-vis spectra. Thus, a new synergistic mechanism of anions and cations is proposed in which the activated thioanisole is used as a nucleophile to attack the peroxomolybdenum bonds, and this provides a new strategy in the design of reliable POM-based catalysts.
- Zhang, Yin,Yu, Wei-Dong,Li, Bin,Chen, Zheng-Fan,Yan, Jun
-
supporting information
p. 14876 - 14884
(2019/11/05)
-
- Carbon nanotube-ruthenium hybrid towards mild oxidation of sulfides to sulfones: Efficient synthesis of diverse sulfonyl compounds
-
A heterogeneous catalyst was assembled with ruthenium nanoparticles on carbon nanotubes and used in a mild oxidation method to prepare sulfones from sulfides. The system proved very efficient on the investigated substrates and the products were obtained in high yields.
- Almeida, Renata G.,De Carvalho, Renato L.,Nunes, Mateus P.,Gomes, Roberto S.,Pedrosa, Leandro F.,De Simone, Carlos A.,Gopi, Elumalai,Geertsen, Valérie,Gravel, Edmond,Doris, Eric,Da Silva Júnior, Eufranio N.
-
p. 2742 - 2748
(2019/06/17)
-
- Water-soluble polymer anchored peroxotitanates as environmentally clean and recyclable catalysts for mild and selective oxidation of sulfides with H2O2 in water
-
Anchoring of peroxotitanium (pTi) species to linear water-soluble acrylic acid based polymers, poly(sodium acrylate) (PA) and poly(sodium methacrylate) (PMA) led to the successful synthesis of a pair of new, water-tolerant and recyclable catalysts of the type [Ti2(O2)2O2(OH)2]4-—L (L = PA or PMA), highly effective in chemoselective sulfoxidation of organic sulfides with 30% H2O2 in aqueous medium at ambient temperature. The catalytic protocol is high yielding (TOF up to 11,280 h?1), operationally simple as well as environmentally clean and safe, being free from halide, or any other toxic auxiliaries. The catalysts are sufficiently stable to afford easy recyclability for at least 10 consecutive reaction cycles of sulfoxidation with consistent activity selectivity profile. Oxidation of dibenzothiophene (DBT) to respective high purity sulfoxide or sulfone could also be accomplished using the same catalysts by variation of reaction conditions.
- Ahmed, Kabirun,Saikia, Gangutri,Paul, Sivangi,Baruah, Satyajit Dey,Talukdar, Hiya,Sharma, Mitu,Islam, Nashreen S.
-
-
- Switchable Synthesis of Aryl Sulfones and Sulfoxides through Solvent-Promoted Oxidation of Sulfides with O2/Air
-
A practical and switchable method for the synthesis of aryl sulfones and sulfoxides via sulfide oxidation was developed. The chemoselectivities of products were simply controlled by reaction temperature using O2/air as the terminal oxidant and oxygen source. The broad substrate scope, easy realization of gram-scale production, and the simplification of a sulfide oxidation system render the strategy attractive and valuable.
- Cheng, Zhen,Sun, Pengchao,Tang, Ailing,Jin, Weiwei,Liu, Chenjiang
-
supporting information
p. 8925 - 8929
(2019/11/14)
-