- The vibrational spectra and rotational isomerism of methyl ethyl sulphone-d0, -d3 and -d5
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The infrared and Raman spectra of methyl ethyl sulphone, methyl ethyl sulphone-1,1,1-d3 and methyl ethyl sulphone-1,1,1,3,3-d5 have been presented with vibrational assignmets.Two solid states have been identified in which the molecules are either the trans or the gauche rotational isomers: one solid, the A form, occurs in cooled KBr disks used for infrared spectra while the other was found in CsI disks under ambient conditions.A mixed crystal form has also been found.In the liquid state the enthalpy of the B rotational isomer is slightly less than that of the A isomer by 90 (+/- 140) J mol-1.
- Fawcett, Allan H.,Fee, Sean,Stuckey, Michael,Walkden, Peter
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- Accurate Regulating of Visible-Light Absorption in Polyoxotitanate-Calix[8]arene Systems by Ligand Modification
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With use of a macrocyclic polyphenol, tert-butylcalix[8]arene (TBC[8]), as ligands, a series of TBC[8]-stabilized {Ti4O2}clusters, containing penta- and hexacoordinated Ti centers, were synthesized. Such complexes are "core-shell" shaped containing a {Ti4O2} core arranged in a zigzag fashion. While outer walls of the clusters are decorated by deprotonated TBC[8], their upper and lower surfaces can be modified by various O- or N-donor ligands, and the ratio of the penta- and hexacoordinated Ti(IV) centers in the {Ti4O2} core can be precisely regulated from 4:0, to 3:1, to 2:2, to 1:3, and finally to 0:4. The combined coordination of different ligands in the axial direction shows significant influence on the adsorption of the TBC[8]-Ti4 system in the visible-light region, and their absorption edge can be precisely regulated from 600 to 700 nm. The above structural functionalization in the TBC[8]-Ti4 system also tunes their photocatalytic H2 production activities and oxidative desulfurization ability. Thus, for the first time, by confining the polyoxotitanium cluster in macrocyclic molecules, we provide an example of understanding the structure-property relationship of titanium-oxygen materials by ligand modification.
- Liu, Chao,Yang, Xin-Xue,Yi, Xiao-Yi,Yu, Wei-Dong
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- Ionic Liquid Stabilized Niobium Oxoclusters Catalyzing Oxidation of Sulfides with Exceptional Activity
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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
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p. 4206 - 4217
(2019/03/26)
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- Organophosphonate-Functionalized Lanthanopolyoxomolybdate: Synthesis, Characterization, Magnetism, Luminescence, and Catalysis of H2O2-Based Thioether Oxidation
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A novel class of organophosphonate-based polyoxomolybdate derivatives, K4H5[Ln3(H2O)14{(Mo8O24)(O3PCH2COO)3}2]·23H2O (Ln = Gd (1Gd), Tb (2Tb), Dy (3Dy)), have been fully investigated by a few characterization methods such as single-crystal X-ray crystallography, XRPD, elemental analysis, TGA, and IR spectra. The magnetic properties of 1Gd, 2Tb, and 3Dy were investigated, as well as the solid-state luminescence properties of 2Tb and 3Dy. The catalysis properties of 1Gd, 2Tb, and 3Dy for thioether oxidization have been investigated using hydrogen peroxide (H2O2) as an oxidant. The catalysis study demonstrated the efficient and selective conversion of various thioethers to their corresponding sulfones in excellent yields.
- Wang, Jiawei,Niu, Yanjun,Zhang, Meng,Ma, Pengtao,Zhang, Chao,Niu, Jingyang,Wang, Jingping
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p. 1796 - 1805
(2018/02/23)
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- Synthesis and characterization of a Sb(v)-containing polyoxomolybdate serving as a catalyst for sulfoxidation
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A Sb-containing Anderson-based polyoxomolybdate cluster, [(CH3)4N]4H8[Na5Sb3(Sb2Mo12O57)]·17H2O [1; (CH3)4N+ = TMA+], has been successfully synthesized by using an aqueous solution method and structurally characterized. In particular, UV-Vis spectroscopy has been employed to elucidate the stability of the polyoxoanions. Under mild conditions, the catalyst demonstrates high activity and selectivity for the sulfoxidation of various sulfides in the presence of hydrogen peroxide. For example, thioanisole undergoes up to 100% conversion and 100% sulfone selectivity at 25 °C in aqueous solution.
- Lu, Jingkun,Wang, Yaping,Ma, Xinyi,Niu, Yanjun,Singh, Vikram,Ma, Pengtao,Zhang, Chao,Niu, Jingyang,Wang, Jingping
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p. 8070 - 8077
(2018/06/29)
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- A Crown-Shaped Ru-Substituted Arsenotungstate for Selective Oxidation of Sulfides with Hydrogen Peroxide
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An acetate-bridged Ru-substituted arsenotungstate [H2N(CH3)2]14[As4W40O140{Ru2(CH3COO)}2]?22 H2O (1) has been synthesized and structurally characterized. Four Ru atoms occupy the respective lacunary S2 sites of the crown-shaped polyanion [As4W40O140]28?, and each Ru atom is coordinated by one As atom and five μ2-O atoms, comprising four from the S2 site and one from the acetate ligand. To the best of our knowledge, this coordination of the Ru atom, with an Ru?As bond length of 2.377(3)–2.387(3) ?, is unprecedented in polyoxometalate (POM) chemistry. Notably, 1 exhibits high efficiency, excellent selectivity, and good recyclability for the oxidation of sulfides with hydrogen peroxide (H2O2). Catalytic oxidation of various sulfides in the presence of 1 gives superior conversion and selectivity for sulfones in acetonitrile, whereas sulfoxides are obtained in methanol.
- Han, Mengdan,Niu, Yanjun,Wan, Rong,Xu, Qiaofei,Lu, Jingkun,Ma, Pengtao,Zhang, Chao,Niu, Jingyang,Wang, Jingping
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p. 11059 - 11066
(2018/08/09)
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- The Polyoxovanadate-Based Carboxylate Derivative K6H[VV17VIV12(OH)4O60(OOC(CH2)4COO)8]·nH2O: Synthesis, Crystal Structure, and Catalysis for Oxidation of Sulfides
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The high-nuclearity polyoxovanadate-based carboxylate derivative K6H[VV17VIV12(OH)4O60(OOC(CH2)4COO)8]·nH2O (1) has been successfully synthesized by conventional aqueous methods and structurally characterized. The [VV17VIV12(OH)4O60(OOC(CH2)4COO)8]7- polyanion is built up from three cages: one {VV17(OH)4O44} cage and two identical [(VIV3O6)2(OOC(CH2)4COO)4]8- cages. Of the three cages, the {VV17(OH)4O44} is a purely inorganic polyoxovanadate cluster, whereas each of the [(VIV3O6)2(OOC(CH2)4COO)4]8- cages is a vanadium-based organic-inorganic hybrid cluster framed via four adipate ligands linking simultaneously to two triangular {V3} units. The two [(VIV3O6)2(OOC(CH2)4COO)4]8- cages are covalently attached to the central {VV17(OH)4O44} cage via V-O-V bonds in a linear arrangement, resulting in a {V29}-based hybrid cluster skeleton. The catalytic properties of compound 1 for the oxidation of sulfides by tert-butyl hydroperoxide were investigated, and the result indicates that 1 exhibits excellent catalytic activity for the oxidation of sulfides under mild conditions.
- Wang, Ke,Niu, Yanjun,Zhao, Dongyan,Zhao, Yanxin,Ma, Pengtao,Zhang, Dongdi,Wang, Jingping,Niu, Jingyang
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p. 14053 - 14059
(2017/11/27)
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- Method for preparing ethyl methyl sulfone
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The invention relates to a method for preparing ethyl methyl sulfone. According to the method, ethyl methyl sulfide serves as a raw material, glacial acetic acid serves as a catalyst, hydrogen peroxide serves as an oxidant, the stirring reaction is performed for 4-5 h at 60-80 DEG C; and after the reaction is over, reaction fluid undergoes aftertreatment to obtain ethyl methyl sulfone. According to the method, the homogeneous catalysis glacial acetic acid is adopted and is low in cost, and the reaction is easy to operate. The reaction conditions are mild, the production cycle is short, and the yield can be 90% or above.
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Paragraph 0019
(2017/03/08)
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- A reusable catalytic system for sulfide oxidation and epoxidation of allylic alcohols in water catalyzed by poly(dimethyl diallyl) ammonium/polyoxometalate
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An effective catalyst based on a polyoxometalate and a polymer has been developed for the oxidation of sulfides and allylic alcohols under mild conditions in water. The synthetic procedure to form the catalyst and the separation of the products are convenient, and the system is reusable.
- Zhao, Wei,Yang, Chunxia,Cheng, Zhiguo,Zhang, Zhenghui
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supporting information
p. 995 - 998
(2016/02/27)
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- Synthesis and characterization of 3-[N,N′-bis-3-(salicylidenamino) ethyltriamine] Mo(vi)O2@SBA-15: A highly stable and reusable catalyst for epoxidation and sulfoxidation reactions
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The efficient and reusable oxidation catalyst 3-[N,N′-bis-3- (salicylidenamino)ethyltriamine] Mo(vi)O2@SBA-15 has been synthesized by the anchoring of the 3-[N,N-bis-3-(salicylidenamino)ethyltriamine] ligand (L or Salpr) on the inner surfaces of organofunctionalized SBA-15 and subsequent complexation with Mo(vi)O2(acac)2. The physico-chemical properties of the functionalized catalysts were analyzed by elemental analysis, ICP-OES, XRD, N2-sorption measurements, TG & DTA, solid state 13C, 29Si NMR spectroscopy, FT-IR, Raman spectroscopy, XPS, DRS UV-Vis spectroscopy, SEM and TEM. XRD and N2 sorption analyses helped to find out the morphological and textural properties of the synthesized catalysts and confirm that an ordered mesoporous channel structure was retained even after the multistep synthetic procedures. The (100), (110) and (200) reflections in SBA-15 provide hints of a good structural stability, the existence of long range ordering and a high pore wall thickness. TG and DTA results reveal that the thermal stability of (L)Mo(vi)O2@SBA-15 was maintained up to 300°C. The organic moieties anchored over the surface of the SBA-15 support were determined by solid state 13C NMR and FT-IR spectroscopy. Further, solid state 29Si NMR spectroscopy provides the information about the degree of functionalization of the surface silanol groups with the organic moiety. The electronic environment and the oxidation state of the molybdenum site in (L)Mo(vi)O2@SBA-15 were monitored by Raman spectroscopy, XPS and DRS UV-Vis techniques. Moreover, the morphology and topographic information of the synthesized catalysts were confirmed by SEM and TEM imaging. The synthesized catalysts were evaluated in epoxidation and sulfoxidation reactions, and the results show that (L)Mo(vi)O2@SBA-15 exhibits high conversion and selectivity towards epoxidation and sulfoxidation reactions in combination with high stability. The anchored solid catalysts can be recycled effectively and reused several times without major loss in activity. In addition, Sheldon's hot filtration test was also carried out.
- Lazar, Anish,Thiel, Werner R.,Singh
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p. 14063 - 14073
(2014/04/17)
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- A peroxotungstate-ionic liquid brush assembly: An efficient and reusable catalyst for selectively oxidizing sulfides with aqueous H2O 2 solution in neat water
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An efficient and reusable heterogeneous catalytic assembly of peroxotungstate held in a ionic liquid (IL) brush was synthesized and an environmentally-friendly procedure was developed for selective oxidation of sulfides at room temperature using 30 wt.percent hydrogen peroxide as the terminal oxidant and water as a sole solvent. No organic co-solvent or other additive was needed. A 1.5-2.0 molpercent (based on W atom) loading catalyst was found to be sufficient for a smooth and clean reaction. Both aliphatic and aromatic sulfides were efficiently and selectively transformed into their respective sulfoxides or sulfones by simply controlling of equivalents of hydrogen peroxide. In addition to the high catalytic activity, the catalyst exhibits excellent chemoselectivity. Sensitive functional groups, such as double bond and hydroxyl, remained under the oxidation conditions the reaction even with an excess hydrogen peroxide. The catalyst was easily recovered (via simple filtration) and reused at least eight times without a noticeable loss of activity. ?2012 Sociedade Brasileira de Qui?mica.
- Shi, Xianying,Ma, Wenjuan,Ou, Hui,Han, Xiaoyan,Lu, Congmin,Chen, Yan,Wei, Junfa
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p. 1536 - 1542
(2012/11/07)
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- Peroxotungstates immobilized on multilayer ionic liquid brushes-modified silica as an efficient and reusable catalyst for selective oxidation of sulfides with H2O2
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Peroxotungstates held in a series of different supported ionic liquid brush catalysts were synthesized and characterized. Their catalytic performance towards the selective oxidation of sulfides with aqueous hydrogen peroxide was investigated under mild conditions. We found that the catalytic activities of the different catalysts depend on the number of supported ionic liquid layers and N-end-capped alkyl group on the imidazole ring. The highest yield of methyl phenyl sulfoxide was obtained using the BisILs-C8H17-W2 catalyst under optimum conditions. The sulfides were selectively oxidized to sulfoxides in high yields with trace sulfones detected by GC upon using 1.1 equivalents of H2O2. At 2.5 equivalents of H 2O2 the sulfones were found to be the main products. It is noteworthy that the catalyst resulted in high chemoselectivity towards sulfur groups with unsaturated double bonds even though excess hydrogen peroxide was used in addition to exhibiting high catalytic activity. There was no apparent loss of catalytic efficiency until the 8th cycle.
- Shi, Xianying,Han, Xiaoyan,Ma, Wenjuan,Wei, Junfa,Li, Jing,Zhang, Qiang,Chen, Zhanguo
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experimental part
p. 57 - 62
(2011/07/30)
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- Oxidoperoxidotungsten(VI) complexes with secondary hydroxamic acids: Synthesis, structure and catalytic uses in highly efficient, selective and ecologically benign oxidation of olefins, alcohols, sulfides and amines with H2O2 as a terminal oxidant
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The reaction of a solution of freshly precipitated WO3 in H 2O2 separately with the secondary hydroxamic acids N-benzoyl-N-phenylhydroxamic acid (BPHAH), N-benzoyl-Northo-tolylhydroxamic acid (BOTHAH), N-benzoyl-N-meta-tolylhydroxamic acid (BMTHAH), N-benzoyl-N-para- tolyl-hydroxamic acid (BPTHAH) and N-cinnamyl-N-phenylhy-droxamic acid (CPHAH) afforded [WO(O2)(BPHA)2] (1), [WO(O2)(BOTHA) 2] (2), [WO(O2)(BMTHA)2] (3), [WO(O 2)-(BPTHA)2] (4) and [WO(O2)(CPHA)2] (5), respectively. Aqueous tungstate solution, on reaction with all these hydroxamic acids, produced [W(O)2(hydroxamato)2] (6). The complexes show excellent catalytic functions in the oxidation of (a) olefins at room temperature in the presence of NaHCO3 as promoter, (b) alcohols, sulfides and amines, at reflux, with H2O2 as a terminal oxidant, yielding a high turnover number (TON), the highest being for olefin-to-epoxide conversion. An attempt to synthesize peroxide-rich complexes of the type PPh4[WO(O2)2(hydroxamato)] (7), for example PPh4[WO-(O2)2BMTHA] (7C), resulted in the isolation of PPh4[WO-(O2)2(C 6H5COO)] (8), which was probably obtained by the hydrolysis of coordinated BMTHA. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
- Maiti, Swarup K.,Dinda, Subhajit,Banerjee, Surajit,Mukherjee, Alok K.,Bhattacharyya, Ramgopal
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experimental part
p. 2038 - 2051
(2009/03/11)
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- Unexpected steric effects of "remote" alkyl groups on the rate of conjugate additions to alkyl α,β-ethylenic sulfones, sulfoxides, and esters
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Examination of conjugated ethylenic sulfones, sulfoxides, and esters in Michael-type addition reactions reveals, for the first time, that the size of the heteroatom-attached alkyl group affects the rate of conjugate addition. Molecular modeling strongly suggests that what are generally considered to be "remote" alkyl groups in -CβH=CαHS(O) n,-alkyl systems and -CH2CβH=C αHCOO-alkyl systems are actually not remote from the β-carbon atom of the Michael accepting unit. Molecular modeling clearly shows that the alkyl groups in these Michael acceptors shield the β-carbons in the following order: Et i-Pr > t-Bu.
- Usera, Aimee R.,Posner, Gary H.
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p. 2329 - 2334
(2007/10/03)
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- Oxoperoxo molybdenum(VI) and tungsten(VI) and oxodiperoxo molybdate(VI) and tungstate(VI) complexes with 8-quinolinol: Synthesis, structure and catalytic activity
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A solution obtained by dissolving MoO3 in a moderate excess of H2O2 reacts with 8-quinolinol (QOH) to give [MoO(O 2)(QO)2] (1), but, when the same reaction is conducted with a large excess of H2O2, an anionic complex is formed, which reacts with PPh4Cl to give the corresponding salt [MoO(O 2)2(QO)][PPh4] (2 · PPh4). Freshly prepared WO3 behaves the same way and, depending on the amount of H2O2 used, as above, produces either [WO(O 2)(QO)2] (3) or [WO(O2)2(QO)] [PPh4] (4 · PPh4), respectively. Crystallographic analyses reveal the coordination geometries around the metal center in these complexes to be distorted pentagonal bipyramids. These compounds show interesting catalytic properties in the oxidation of alcohols using H 2O2 as the terminal oxidant. In the case of aromatics, including benzylic and cinnamylic alcohols, the oxidation occurs selectively, affording aldehydes or ketones with reasonably high turnover numbers. Taking benzyl alcohol as a representative case, a probable mechanism of the alcohol-to-aldehyde conversion mediated by the prepared catalysts is suggested. The oxidation of aliphatic primary alcohols, under the same conditions, does not show the above selectivity: the reaction yields the corresponding aldehydes as well as carboxylic acids. The work was also extended to study the catalytic activity towards the oxidation of phenol and various sulfides and amines using the same oxidants. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2005.
- Maiti, Swarup K.,Banerjee, Surajit,Mukherjee, Alok K.,Abdul Malik,Bhattacharyya, Ramgopal
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p. 554 - 563
(2007/10/03)
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- Liquid-phase oxidation of sulfides by an aluminum (and titanium) tert-butoxide - tert-butyl hydroperoxide system
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A system aluminum (and titanium) tert-butoxide-tert-butyl hydroperoxide (1 : 2) under mild conditions (20°C, 1 h) oxidizes aliphatic and alkylaromatic sulfides and diphenyl sulfide to the corresponding sulfones in yields close to ~100%. The oxidation is induced by electron-excited dioxygen formed upon thermal decomposition of intermediate metal-containing peroxy trioxides (ozonides). The latter are formed as a result of the reversible reaction of aluminum or titanium tert-butoxides with tert-butyl hydroperoxide followed by the interaction of di-tert-butoxy-tert-butylperoxyaluminum and tri-tert-butoxy-tert-butylperoxytitanium that formed with another Bu tOOH molecule. Alkminum-containing peroxide (ButO) 2AlOOBut oxidizes sulfides to sulfoxides.
- Dodonov,Zaburdaeva,Stepovik
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p. 1729 - 1734
(2007/10/03)
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- Method of producing 4-nitro-m-phenylenediamine sulfate
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A method of manufacture of 4-nitro-m-phenylenediamine sulfate is taught. The resultant compound is useful in the dyeing of keratinic fibers, particularly, human hair. It exhibits reduced toxicity and potential for damage to such fibers, and is easier to remove than are other known compounds.
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- Bi or Cd-induced coupling of sulfonyl chlorides with allylic halides. A simple synthesis of allylic sulfones
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The bismuth or cadmium-catalyzed coupling reaction between aryl and alkyl sulfonyl chlorides and allylic halides proceeds smoothly to provide excellent yields of allylic sulfones at ambient temperature.
- Baruah, Mukulesh,Boruah, Anima,Prajapati, Dipak,Sandhu, Jagir S.
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p. 1083 - 1084
(2007/10/03)
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- Palladium Catalyzed Hydrogenation of α,β-Unsaturated Sulfones and Phosphonates
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The binuclear palladium complex, 2, when treated with oxygen, catalyzes the hydrogenation of the double bond of α,β-unsaturated sulfones and phosphonates in THF at room temperature and 1 atm of hydrogen pressure.Saturated sulfones and phosphonates were isolated in 49-93percent yields.
- Cho, In Sik,Alper, Howard
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p. 4027 - 4028
(2007/10/02)
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- Cathodic cleavage of heteroarylalkylsulfones: A facile route to long chain aliphatic sulfinates and relevant sulfones
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Heteroarylalkylsulfones - mainly pyridylalkylsulfones - exhibit a cathodic cleavage reaction producing alkanesulfinate anion in high yield. This reaction is tested with long chain alkyl groups and allows an easy synthesis of aliphatic sulfinic acids.
- Delaunay,Mabon,Chaquiq El Badre,Orliac,Simonet
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p. 2149 - 2150
(2007/10/02)
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- Triazinyl reactive dyestuffs in which triazinyl group is further substituted with a beta-chloroethylsulfonyl- or vinylsulfonylbutyrylamino moiety
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Reactive dyes of the formula STR1 in which D is the radical of an organic dye of the monoazo, polyazo, metal complex azo, anthraquinone, phthalocyanine, formazan, azomethine, dioxazine, phenazine, stilbene, triphenylmethane, xanthene, thioxanthrone, nitroaryl, naphthoquinone, pyrenequinone or perylenetetracarbimide series, R is hydrogen or substituted or unsubstituted C1-4 -alkyl, X is a substituent which is detachable as an anion, B is a radical of the formula STR2 R1 and R2, independently of each other, are hydrogen or substituted or unsubstituted C1-4 -alkyl or phenyl, A is a substituted or unsubstituted aliphatic or aromatic bridge member, Y is a --CO--Z or --SO2 --Z radical, Z is an aliphatic, aromatic or heterocyclic reactive radical, and n is 1 or 2, are suitable for dyeing or printing cellulose-containing and nitrogen-containing materials and in high dyeing yield produce dyeings and prints having good fastness properties.
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- Search for New Membrane-active Substances: Synthesis of Tropan-3-ols with Alkyl, Alkenyl and Alkenynyl Groups at the Bridgehead
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The synthesis of tropan-3-ols with alkyl, alkenyl and alkynyl groups at the bridgehead is described.The new compounds have been considered as new membrane-active substances that would serve as model compounds for histrionicotoxin (1).Application of the Noyori route to 2-substituted pyrroles was unsuccessful.In order to avoid difficulties in obtaining individual long-chain 4-keto aldehydes for the Robinson condensation of each new model compound a key tropane intermediate (8) was prepared instead.The first attempts to extend the chains of the mesyl ester of the diol (8b) and iodomethyltropanol (9b) by Grignard type coupling failed.Therefore we embarked on a Wittig reaction of the tropane-1-carbaldehyde (11) synthesized in high yield from the diol (8).Indeed, both pent-1-enyl- and pentyl-tropanols, (12) and (13) were obtained.Coupling with an acetylenic phosphorane led to the pent-1-enynyltropanol (14).A further new key compound, namely 3β-acetoxytropan-1-ylacetaldehyde (15) was also synthesized as a precursor to conjugated tropanyl enynes which would more closely resemble the natural product (1).
- Dharanipragada, Ramalinga,Fodor, Gabor
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p. 545 - 550
(2007/10/02)
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- Possible Anthelmintic Agents: Syntheses of Various Imidazoquinazolinone Carbamates
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Two of the three possible imidazoquinazolinone-2-carbamates representing angular and linear heterocyclic systems, have been synthesised and evaluated for their anthelmintic activity.During the course of the synthesis of ethyl or methyl 7-alkylimidazoquinazolin-8-one-2-carbamate, it is observed that the reaction of 3-alkyl-7-chloro-6-nitroquinazolin-4-ones with butanol saturated with aq.NH3, furnishes a number of ring-opened products which have been characterised on the basis of elemental analyses, IR, PMR and mass spectral data.The same reaction when carried out with dry NH3, furnishes the desired amino-nitro derivatives.UV and IR spectra of the linear and angular imidazoquinazolinones have also been compared.
- Kumar, Shiv,Kansal, V. K.,Bhaduri, A. P.
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p. 1068 - 1071
(2007/10/02)
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