940-12-5Relevant academic research and scientific papers
Chiral Ligands in Hypervalent Iodine Compounds: Synthesis and Structures of Binaphthyl-Based λ3-Iodanes
Zhang, Huaiyuan,Cormanich, Rodrigo A.,Wirth, Thomas
supporting information, (2021/12/22)
Several novel binaphthyl-based chiral hypervalent iodine(III) reagents have been prepared and structurally analysed. Various asymmetric oxidative reactions were applied to evaluate the reactivities and stereoselectivities of those reagents. Moderate to excellent yields were observed; however, very low stereoselectivities were obtained. NMR experiments indicated that these reagents are very easily hydrolysed in either chloroform or DMSO solvents leading to the limited stereoselectivities. It is concluded that the use of chiral ligands is an unsuccessful way to prepare efficient stereoselective iodine(III) reagents.
Polyoxometalate-Based Organic-Inorganic Hybrids as Heterogeneous Catalysts for Cycloaddition of CO2with Epoxides and Oxidative Desulfurization Reactions
Zhao, Yu-Qing,Liu, Ying-Ying,Ma, Jian-Fang
, p. 1019 - 1027 (2021/01/13)
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.
Self-Assembled Polyoxometalate-Based Metal-Organic Polyhedra as an Effective Heterogeneous Catalyst for Oxidation of Sulfide
Gan, Hong-Mei,Qin, Chao,Zhao, Liang,Sun, Chunyi,Wang, Xing-Long,Su, Zhong-Min
, p. 1028 - 1034 (2021/01/26)
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.
Assembly of polyoxometalate-thiacalix[4]arene-based inorganic-organic hybrids as efficient catalytic oxidation desulfurization catalysts
Li, Jie,Du, Peng,Liu, Ying-Ying,Ma, Jian-Fang
supporting information, p. 1349 - 1356 (2021/02/09)
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.
Tetrameric Lanthanide-Substituted Silicotungstate {Ln8Si4W40} Nanoclusters: Synthesis, Structural Characterization, Electrochemistry, and Catalytic Application for Oxidation of Thioethers
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)
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.
Air atmospheric photocatalytic oxidation by ultrathin C,N-TiO2nanosheets
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)
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.
A {Ti6W4}-Cluster-Substituted Polyoxotungstate: Synthesis, Structure, and Catalytic Oxidation Properties
Li, Hai-Lou,Lian, Chen,Yang, Guo-Yu
supporting information, p. 14622 - 14628 (2021/10/01)
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.
Diastereoselective oxidation of menthyl arenesulfenates to sulfinates and access to enantioenriched aryl methyl sulfoxides
Hamel, Matthieu,Vazeux, Michel,Gulea, Mihaela
, p. 6137 - 6143 (2021/07/12)
Three aryl methyl sulfoxides were prepared via the following sequence: synthesis of the menthyl arenesulfenate from the corresponding thiol, diastereoselective oxidation leading to the sulfinate, then reaction with a Grignard reagent. The aryl moiety was substituted with a methyl ester on the ortho position or a nitro group on the ortho or the para position. The sulfenate esters were obtained in fair to excellent yield (42–82%). Four different oxidizing agents were tested to obtain the corresponding sulfinate esters with diastereomeric excesses (de) ranging from 10 to 48%. After separation of the diastereomers and reaction with methyl Grignard reagent, two enantiopure sulfoxides and one enantioenriched sulfoxide (32% ee) were obtained.
NOVEL IMIDAZO-PYRAZINE DERIVATIVES
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Page/Page column 45; 130, (2021/12/31)
The invention provides novel imidazo-pyrazine derivatives having the general formula (I), and pharmaceutically acceptable salts thereof, wherein X, m, n, and R1to R3 are as described herein: formula (I). Further provided are pharmace
Electrochemical oxygenation of sulfides with molecular oxygen or water: Switchable preparation of sulfoxides and sulfones
Li, Jin-Heng,Li, Yang,Sun, Qing,Xue, Qi,Zhang, Ting-Ting
supporting information, p. 10314 - 10318 (2021/12/17)
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
