- MONOACYLGLYCEROL LIPASE MODULATORS
-
Fused and bridged compounds of Formula (I), and pharmaceutically acceptable salts, isotopes, N-oxides, solvates, and stereoisomers thereof, pharmaceutical compositions containing them, methods of making them, and methods of using them including methods for treating disease states, disorders, and conditions associated with MGL modulation, such as those associated with pain, psychiatric disorders, neurological disorders (including, but not limited to major depressive disorder, treatment resistant depression, anxious depression, autism spectrum disorders, Asperger syndrome, bipolar disorder), cancers and eye conditions: (I) wherein R1a, R1b, R2, and R3, are defined herein.
- -
-
Page/Page column 75; 84
(2021/10/02)
-
- Monoacylglycerol Lipase Modulators
-
Bridged compounds of Formula (I) and Formula (II), pharmaceutical compositions containing them, methods of making them, and methods of using them including methods for treating disease states, disorders, and conditions associated with MGL modulation, such as those associated with pain, psychiatric disorders, neurological disorders (including, but not limited to major depressive disorder, treatment resistant depression, anxious depression, bipolar disorder), cancers and eye conditions. wherein R2, R3 R4, R5 and R6 are defined herein.
- -
-
Paragraph 0410; 0437
(2020/04/24)
-
- A Bioorthogonal Click Chemistry Toolbox for Targeted Synthesis of Branched and Well-Defined Protein–Protein Conjugates
-
Bioorthogonal chemistry holds great potential to generate difficult-to-access protein–protein conjugate architectures. Current applications are hampered by challenging protein expression systems, slow conjugation chemistry, use of undesirable catalysts, or often do not result in quantitative product formation. Here we present a highly efficient technology for protein functionalization with commonly used bioorthogonal motifs for Diels–Alder cycloaddition with inverse electron demand (DAinv). With the aim of precisely generating branched protein chimeras, we systematically assessed the reactivity, stability and side product formation of various bioorthogonal chemistries directly at the protein level. We demonstrate the efficiency and versatility of our conjugation platform using different functional proteins and the therapeutic antibody trastuzumab. This technology enables fast and routine access to tailored and hitherto inaccessible protein chimeras useful for a variety of scientific disciplines. We expect our work to substantially enhance antibody applications such as immunodetection and protein toxin-based targeted cancer therapies.
- Baalmann, Mathis,Bitsch, Sebastian,Deweid, Lukas,Ilkenhans, Nadja,Kolmar, Harald,Neises, Laura,Schneider, Hendrik,Werther, Philipp,Wilhelm, Jonas,Wolfring, Martin,Wombacher, Richard,Ziegler, Michael J.
-
supporting information
p. 12885 - 12893
(2020/06/02)
-
- Aerobic oxidation of the C-H bond under ambient conditions using highly dispersed Co over highly porous N-doped carbon
-
Highly dispersed Co sites in highly porous N-doped carbon (Co-NC) were synthesized by high-temperature pyrolysis of Zn/Co bimetallic zeolitic imidazolate framework-8 (CoxZn100-x-ZIF). Wide characterization indicated that the pyrolysis atmosphere and temperature play crucial roles in the metal dispersion and pore structure of the resulting materials. A hydrogen treatment at elevated temperatures is found to favour the Zn volatilization and restrict the pore shrinkage of the ZIF precursor, thus yielding efficient catalysts with highly dispersed Co, a high surface area (1090 m2 g-1) and pore volume (0.89 cm3 g-1). When used as a catalyst for aerobic oxidation of ethylbenzene (EB), Co1Zn99-ZIF-800-H2 contributes to 98.9% EB conversion and 93.1% ketone selectivity under mild conditions (60 °C, 1 atm O2), which is 41.3 times more active in comparison to the ZIF-67-derived Co catalyst. Co-NC is stable and could be reused four times without obvious deactivation. This catalyst displays good chemoselectivity to the corresponding ketones when using a broad scope of hydrocarbon compounds.
- Nie, Renfeng,Chen, Jingwen,Chen, Minda,Qi, Zhiyuan,Goh, Tian-Wei,Ma, Tao,Zhou, Lin,Pei, Yuchen,Huang, Wenyu
-
p. 1461 - 1466
(2019/03/26)
-
- Synthesis of functionalized carbon microspheres and their catalyst activity in C—O and C—N bond formation reactions
-
Disclosed herein is a simple process for functionalization/grafting of carbon microspheres obtained from bagasse with various active functional groups onto it and use of the same as catalyst for various organic reactions, having very high selectivity and conversion rate.
- -
-
Page/Page column 9
(2019/02/14)
-
- Photocatalytic Aerobic Phosphatation of Alkenes
-
A catalytic regime for the direct phosphatation of simple, non-polarized alkenes has been devised that is based on using ordinary, non-activated phosphoric acid diesters as the phosphate source and O2 as the terminal oxidant. The title method enables the direct and highly economic construction of a diverse range of allylic phosphate esters. From a conceptual viewpoint, the aerobic phosphatation is entirely complementary to traditional methods for phosphate ester formation, which predominantly rely on the use of prefunctionalized or preactivated reactants, such as alcohols and phosphoryl halides. The title transformation is enabled by the interplay of a photoredox and a selenium π-acid catalyst and involves a sequence of single-electron-transfer processes.
- Depken, Christian,Kr?tzschmar, Felix,Rieger, Rene,Rode, Katharina,Breder, Alexander
-
supporting information
p. 2459 - 2463
(2018/01/27)
-
- Identification of in situ flower volatiles from kiwifruit (Actinidia chinensis var. deliciosa) cultivars and their male pollenisers in a New Zealand orchard
-
In situ flower volatiles from six kiwifruit cultivars (Actinidia chinensis var. deliciosa); ‘Hayward’, ‘Chieftain’, ‘M56’, ‘Zes007’ (Green11), ‘M36’, and ‘M43’ were collected by dynamic headspace sampling. Forty-five compounds were detected in the headspace of the flowers, with straight chain hydrocarbons and terpenes accounting for >98% of the volatiles emitted quantitatively across the six cultivars. Of these hydrocarbons, (3Z,6Z,9Z)-heptadecatriene is reported for the first time from a floral source while (8Z)-hexadecene and (9Z)-nonadecene are reported for the first time from kiwifruit flowers. All three hydrocarbons were verified by synthesis. Quantitative comparison of the six honey bee perceived compounds from the headspace of the cultivars showed that the males ‘M36’ and ‘M43’ closely matched the female cultivar Green11 that they are used to pollinate. Males ‘M56’ and ‘Chieftain’ were not as closely matched to the female cultivar ‘Hayward’ that they are used to pollinate. The male ‘M56’ in particular differed significantly from the female ‘Hayward’ in four of the six honey bee perceived compounds.
- Twidle, Andrew M.,Suckling, David M.,Seal, Alan G.,Fedrizzi, Bruno,Pilkington, Lisa I.,Barker, David
-
-
- New multiblock copolymers of norbornene and 5-hydroxycyclooctene
-
Cross-metathesis of 5-hydroxycyclooctene and norbornene homopolymers affords the multiblock copolymer possessing a broad range in the degree of blockiness (from 0.03 to 1).
- Denisova, Yulia I.,Gringolts, Maria L.,Roenko, Alexei V.,Shandryuk, Georgiy A.,Finkelshtein, Eugene Sh.,Kudryavtsev, Yaroslav V.
-
p. 416 - 418
(2017/08/02)
-
- Novel Super-Resolution Imaging Compositions and Methods Using Same
-
The invention provides compositions that may be used for imaging intracellular structures. The invention further provides methods of imaging intracellular structures. In certain embodiments, the compositions of the invention include trans-cyclooctene-containing ceramide lipids and tetrazine-containing rhodamine-related dyes.
- -
-
Paragraph 0139
(2016/05/24)
-
- Co(ii) complexes loaded into metal-organic frameworks as efficient heterogeneous catalysts for aerobic epoxidation of olefins
-
A series of efficient cobalt(ii)-anchored Cr-MOF (Cr-MIL-101-NH2) catalysts, such as Co(ii)@Cr-MIL-101-Sal, Co(ii)@Cr-MIL-101-P2I and Co(ii)@Cr-MIL-101-P3I, have been successfully synthesized by one-pot modification of the terminal amino group with salicylaldehyde, pyridine-2-aldehyde or pyridine-3-aldehyde and anchoring of Co(ii) ions into the mesoporous Cr-MOF supports. The Co(ii)@Cr-MIL-101-P2I catalyst exhibited high catalytic performance for epoxidation of olefins with air as an oxidant due to the nitrogen atom in the pyridine ring as a strong electron-withdrawing substituent, high dispersion of Co(ii) species and high surface area for sufficient contact between the substrate and active sites. The strong coordination interaction between the Co(ii) ions and chelating groups in the Co(ii)@Cr-MIL-101-P2I catalyst guaranteed the excellent recycling performance. Furthermore, the synthesized Co(ii)@Cr-MIL-101-P2I catalyst realized its general applicability towards various olefins, such as cyclic olefins, tri-substituted olefins, aliphatic olefins and aromatic olefins.
- Wang, Jingjing,Yang, Mu,Dong, Wenjun,Jin, Zhaokui,Tang, Jia,Fan, Shuang,Lu, Yunfeng,Wang, Ge
-
p. 161 - 168
(2015/12/31)
-
- Regioselective Cleavage of Electron-Rich Double Bonds in Dienes to Carbonyl Compounds with [Fe(OTf)2(mix-BPBP)] and a Combination of H2O2 and NaIO4
-
A method for the regioselective transformation of dienes to carbonyl compounds has been developed. Electron-rich olefins react selectively to yield valuable aldehydes and ketones. The method is based on the catalyst [Fe(OTf)2(mix-BPBP)] with an oxidant combination of H2O2 (1.0 equiv.) and NaIO4 (1.5 equiv.); it uses mild conditions and short reaction times, and it outperforms other olefin cleavage methodologies. The combination of an Fe-based catalyst, [Fe(OTf)2(mix-BPBP)], and the oxidants H2O2 and NaIO4 can discriminate between electronically different double bonds and oxidatively cleave the electron-rich bond in dienes to yield aldehydes and ketones in a regioselective manner. The reaction requires mild conditions (0-50 C) and short reaction times (70 min).
- Spannring, Peter,Yazerski, Vital A.,Chen, Jianming,Otte, Matthias,Weckhuysen, Bert M.,Bruijnincx, Pieter C. A.,Klein Gebbink, Robertus J. M.
-
p. 3462 - 3466
(2015/08/06)
-
- Tunable Electrochemical and Catalytic Features of BIAN- and BIAO-Derived Ruthenium Complexes
-
This article deals with a class of ruthenium-BIAN-derived complexes, [RuII(tpm)(R-BIAN)Cl]ClO4 (tpm = tris(1-pyrazolyl)methane, R-BIAN = bis(arylimino)acenaphthene, R = 4-OMe ([1a]ClO4), 4-F ([1b]ClO4), 4-Cl ([1c]ClO4), 4-NO2 ([1d]ClO4)) and [RuII(tpm)(OMe-BIAN)H2O]2+ ([3a](ClO4)2). The R-BIAN framework with R = H, however, leads to the selective formation of partially hydrolyzed BIAO ([N-(phenyl)imino]acenapthenone)-derived complex [RuII(tpm)(BIAO)Cl]ClO4 ([2]ClO4). The redox-sensitive bond parameters involving -N=C-C=N- or -Ni=C-C=O of BIAN or BIAO in the crystals of representative [1a]ClO4, [3a](PF6)2, or [2]ClO4 establish its unreduced form. The chloro derivatives 1a+-1d+ and 2+ exhibit one oxidation and successive reduction processes in CH3CN within the potential limit of ±2.0 V versus SCE, and the redox potentials follow the order 1a+ + + + ≈ 2+. The electronic structural aspects of 1an-1dn and 2n (n = +2, +1, 0, -1, -2, -3) have been assessed by UV-vis and EPR spectroelectrochemistry, DFT-calculated MO compositions, and Mulliken spin density distributions in paramagnetic intermediate states which reveal metal-based (RuII → RuIII) oxidation and primarily BIAN- or BIAO-based successive reduction processes. The aqua complex 3a2+ undergoes two proton-coupled redox processes at 0.56 and 0.85 V versus SCE in phosphate buffer (pH 7) corresponding to {RuII-H2O}/{RuIII-OH} and {RuIII-OH}/{RuIV=O}, respectively. The chloro (1a+-1d+) and aqua (3a2+) derivatives are found to be equally active in functioning as efficient precatalysts toward the epoxidation of a wide variety of alkenes in the presence of PhI(OAc)2 as oxidant in CH2Cl2 at 298 K, though the analogous 2+ remains virtually inactive. The detailed experimental analysis with the representative precatalyst 1a+ suggests the involvement of the active {RuIV=O} species in the catalytic cycle, and the reaction proceeds through the radical mechanism, as also supported by the DFT calculations.
- Hazari, Arijit Singha,Das, Ankita,Ray, Ritwika,Agarwala, Hemlata,Maji, Somnath,Mobin, Shaikh M.,Lahiri, Goutam Kumar
-
p. 4998 - 5012
(2015/05/27)
-
- Non-peripherally alkyl substituted ruthenium phthalocyanines as catalysts in the epoxidation of alkenes
-
Non-peripherally alkyl substituted ruthenium phthalocyanines were demonstrated to be highly active epoxidation catalysts. It is compatible with pyridine N-oxides, and especially 2,6-dichloropyridine N-oxide. The catalytic activity towards a variety of alkenes was comparable to that published for other catalytic systems, but superior in the cases of 1,2-dihydronaphthalene and trans-stilbene. Linear substituents on the non-peripheral sites of the phthalocyanine were able to reduce aggregation and increase the solubility of the catalyst without compromising its activity by steric congestion as all substituted catalysts were more reactive than the unsubstituted phthalocyanine, whereas the bulky isopentyl and cyclohexyl substituted catalysts were less active than those with linear substituents. Although the epoxidation mechanism and the exact active intermediate is still ambigious, it likely involves the coordination of the N-oxide to ruthenium and subsequent transfer of the oxygen to the metal to form a high-valent oxo-ruthenium species. It is proposed that the alkene approaches this metal oxo moiety from the top and that oxygen transfer to the alkene is concerted with concomitant stereoretention.
- Enow, Charles A.,Marais, Charlene,Bezuidenhoudt, Barend C.B.
-
p. 582 - 594
(2015/05/05)
-
- Carbon Dioxide as a Protecting Group: Highly Efficient and Selective Catalytic Access to Cyclic cis-Diol Scaffolds
-
The efficient and highly selective formation of a wide range of (hetero)cyclic cis-diol scaffolds using aminotriphenolate-based metal catalysts is reported. The key intermediates are cyclic carbonates, which are obtained in high yield and with high levels of diastereo- and chemoselectivity from the parent oxirane precursors and carbon dioxide. Deprotection of the carbonate structures affords synthetically useful cis-diol scaffolds with different ring sizes that incorporate various functional groups. This atom-efficient method allows the simple construction of diol synthons using inexpensive and accessible precursors and green metal catalysts and showcases the use of CO2 as a temporary protecting group. Protective Carbon: Aminotriphenolate complexes of FeIII and AlIII are highly efficient and selective catalysts for the conversion of functional (multi)cyclic oxiranes into the corresponding cis carbonates. Basic hydrolysis of the latter provides a series of useful cyclic cis-diol scaffolds in high yield. In this process, CO2 acts as both a temporary protecting group and an oxygen donor.
- Laserna, Victor,Fiorani, Giulia,Whiteoak, Christopher J.,Martin, Eddy,Escudero-Adán, Eduardo,Kleij, Arjan W.
-
supporting information
p. 10416 - 10419
(2016/02/18)
-
- Super-resolution imaging of the Golgi in live cells with a bioorthogonal ceramide probe
-
We report a lipid-based strategy to visualize Golgi structure and dynamics at super-resolution in live cells. The method is based on two novel reagents: a trans-cyclooctene-containing ceramide lipid (Cer-TCO) and a highly reactive, tetrazine-tagged near-IR dye (SiR-Tz). These reagents assemble via an extremely rapid "tetrazine-click" reaction into Cer-SiR, a highly photostable "vital dye" that enables prolonged live-cell imaging of the Golgi apparatus by 3D confocal and STED microscopy. Cer-SiR is nontoxic at concentrations as high as 2 μM and does not perturb the mobility of Golgi-resident enzymes or the traffic of cargo from the endoplasmic reticulum through the Golgi and to the plasma membrane.
- Erdmann, Roman S.,Takakura, Hideo,Thompson, Alexander D.,Rivera-Molina, Felix,Allgeyer, Edward S.,Bewersdorf, Joerg,Toomre, Derek,Schepartz, Alanna
-
supporting information
p. 10242 - 10246
(2015/03/31)
-
- Molybdenum-MCM-41 silica as heterogeneous catalyst for olefin epoxidation
-
MCM-41-supported molybdenum/bis-dithiocarbamate complex can be efficiently utilized, after treatment with tert-butylhydroperoxide (TBHP), for the epoxidation of alkenes under solventless conditions. The treatment with TBHP allows the formation of the real catalyst through oxidative decomposition of the complex affording well dispersed Mo(VI) species grafted onto the silica surface through the silanol groups. Experimental results, catalytic efficiency and spectroscopy data, allow to advance some hypotheses on the molybdenum-grafted catalyst formation. The grafted catalyst can be reused several times in the model epoxidation of cyclohexene affording the epoxide with very good yield; only during the first run a modest molybdenum leaching is observed. Both cyclic and linear alkenes can be epoxidized in good to excellent yields and selectivities.
- Bigi, Franca,Piscopo, Calogero Giancarlo,Predieri, Giovanni,Sartori, Giovanni,Scotti, Roberto,Zanoni, Robertino,Maggi, Raimondo
-
p. 108 - 113
(2014/04/17)
-
- A remote stereochemical lever arm effect in polymer mechanochemistry
-
Molecular mechanisms by which to increase the activity of a mechanophore might provide access to new chemical reactions and enhanced stress-responsive behavior in mechanochemically active polymeric materials. Here, single-molecule force spectroscopy reveals that the force-induced acceleration of the electrocyclic ring opening of gem-dichlorocyclopropanes (gDCC) is sensitive to the stereochemistry of an α-alkene substituent on the gDCC. On the ~0.1 s time scale of the experiment, the force required to open the E-alkene-substituted gDCC was found to be 0.4 nN lower than that required in the corresponding Z-alkene isomer, despite the effectively identical force-free reactivities of the two isomers and the distance between the stereochemical permutation and the scissile bond of the mechanophore. Fitting the experimental data with a cusp model provides force-free activation lengths of 1.67 ± 0.05 and 1.20 ± 0.05 ? for the E and Z isomers, respectively, as compared to 1.65 and 1.24 ? derived from computational modeling.
- Wang, Junpeng,Kouznetsova, Tatiana B.,Kean, Zachary S.,Fan, Lin,Mar, Brendan D.,Martnez, Todd J.,Craig, Stephen L.
-
supporting information
p. 15162 - 15165
(2015/01/16)
-
- Rhodium acetate-catalyzed aerobic Mukaiyama epoxidation of alkenes
-
Mukaiyama epoxidation of alkenes under oxygen catalyzed by rhodium acetate with isobutyraldehyde as the reducing agent is as or more effective than previously reported procedures. A variety of alkenes, including terpenes and cholesterol derivatives, were oxidized. And high regioselectivity for monoepoxidation was observed with neryl, geranyl, and linalyl acetates.
- Shabashov, Dmitry,Doyle, Michael P.
-
p. 10009 - 10013
(2013/11/06)
-
- Force-reactivity property of a single monomer is sufficient to predict the micromechanical behavior of its polymer
-
We demonstrate an accurate prediction of the micromechanical behavior of a single chain of cyclopropanated polybutadiene, which is governed by rapid isomerization of the cyclopropane moieties at ~1.2 nN, from the force-rate correlation of this reaction measured in a small series of increasingly strained macrocycles. The data demonstrate that a single physical quantity, force, uniquely defines the dynamics across length scales from >100 to 1 nm and that strain imposed through molecular design and that imposed by micromanipulation techniques have equivalent effects on the kinetics of a chemical reaction. This represents a new method of screening potential monomers for applications in stress-responsive materials that could also facilitate atomistic interpretations of single-molecule force experiments.
- Akbulatov, Sergey,Tian, Yancong,Boulatov, Roman
-
supporting information; experimental part
p. 7620 - 7623
(2012/06/30)
-
- Guanidinium-based phosphotungstates and ionic liquids as catalysts and solvents for the epoxidation of olefins with hydrogen peroxide
-
Several penta- and hexaalkylated guanidinium-based ionic liquids (GILs) were tested as solvents for the epoxidation of cyclooctene using the Venturello catalyst, [(C8H17)3N(CH3)] 3[PO4{WO(O2)2}4], and hydrogen peroxide as the oxidant. Epoxide yields were obtained in a broad range between 13 and 79 % depending on both the anion and the substituents on the guanidinium moiety. Recycling experiments showed that the catalyst can be used at least three times. Furthermore, new guanidinium phosphotungstates with the PW12O403- anion were synthesized and characterized. Their catalytic performance was evaluated, and GILs as well as acetonitrile were employed as the solvent. Results were compared to those obtained with the comparable ammonium-based catalysts [NR4] 3[PW12O40] (R = C4H9, C6H13) and the analogous imidazolium-based catalyst [BMIM]3[PW12O40] containing the 1-butyl-3-methylimidazolium cation. Employing different GILs as solvents, similar results were obtained for the guanidinium and imidazolium catalysts but significantly lower epoxide yields were obtained using the ammonium catalysts. On using acetonitrile as the solvent, guanidinium-based catalysts exhibited a better performance than the imidazolium catalyst in the case of linear and branched olefins and vice versa in the case of cyclic olefins. Several guanidinium phosphotungstates and guanidinium-based ionic liquids have been synthesized and characterized. Their catalytic performance in epoxidation reactions with hydrogen peroxide was evaluated and compared to similar ammonium and imidazolium compounds. The reaction systems can be recycled and used in at least three consecutive reactions. Copyright
- Gharnati, Loubna,Walter, Olaf,Arnold, Ulrich,Doering, Manfred
-
experimental part
p. 2756 - 2762
(2011/08/02)
-
- Iron-catalyzed epoxidation of aromatic olefins and 1,3-dienes
-
The combination of iron(III) chloride, pyridine-2,6-dicarboxylic acid and formamidine ligands allows for the epoxidation of styrenes and conjugated dienes in excellent chemoselectivity and yields.
- Schroeder, Kristin,Enthaler, Stephan,Join, Benoit,Junge, Kathrin,Beller, Matthias
-
experimental part
p. 1771 - 1778
(2010/09/11)
-
- Synthesis of a molecular charm bracelet via click cyclization and olefin metathesis clipping
-
We describe the synthesis of a polycatenated cyclic polymer, a structure that resembles a molecular charm bracelet. Ruthenium-catalyzed ring-opening metathesis polymerization of an aminocontaining cyclic olefin monomer in the presence of a chain transfer agent generated an α,ω-diazide functionalized polyamine. Cyclization of the resulting linear polyamine using pseudo-high-dilution coppercatalyzed click cyclization produced a cyclic polymer in 19% yield. The click reaction was then further employed to remove linear contaminants from the cyclic polymer using azide- and alkyne-functionalized scavenging resins, and the purified cyclic polymer product was characterized by gel permeation chromatography, 1H NMR spectroscopy, and IR spectroscopy. Polymer hydrogenation and conversion to the corresponding polyammonium species enabled coordination and interlocking of diolefin polyether fragments around the cyclic polymer backbone using ruthenium-catalyzed ring-closing olefin metathesis to afford a molecular charm bracelet structure. This charm bracelet complex was characterized by 1H NMR spectroscopy, and the catenated nature of the small rings was confirmed using two-dimensional diffusionordered NMR spectroscopy.
- Clark, Paul G.,Guidry, Erin N.,Chan, Wing Yan,Steinmetz, Wayne E.,Grubbs, Robert H.
-
supporting information; experimental part
p. 3405 - 3412
(2010/05/01)
-
- Cyclopropenation of alkylidene carbenes derived from α-silyl ketones
-
A new cyclopropanation reaction involving Cα-Si bond insertion of alkylidene carbenes derived from α-silyl ketones has been developed. This unprecedented alkylidene carbene reactivity features excellent selectivity for insertion into Cα-Si bonds rather than insertion into Cγ-H bonds or addition to,δ-double or -triple bonds. The selectivity trend clearly indicates that the α-oxygen in the tether significantly promotes Cγ-H insertion, although the Cα-Si bond insertion still competes effectively.
- Li, Jingwei,Sun, Chunrui,Lee, Daesung
-
supporting information; experimental part
p. 6640 - 6641
(2010/07/04)
-
- High-activity, single-site mesoporous WO3-MCF materials for the catalytic epoxidation of cycloocta-1,5-diene with aqueous hydrogen peroxide
-
For the first time, the high-activity, single-site mesoporous WO3-MCF materials were synthesized and characterized by N2 sorption, TEM, UV-vis DRS, UV-Raman, and XPS. It was found that the dispersion and nature of the tungsten species depend strongly on the tungsten oxide content and the support characteristic. The novel catalyst remains a highly ordered mesostructure of the silica support. The catalytic performance of the materials in the epoxidation of cycloocta-1,5-diene with aqueous H2O2 was investigated. The excellent catalytic performance of WO3-MCF in the selective oxidation of cycloocta-1,5-diene was attributed to the presence of isolated tetrahedral {WO4} species and the unique pore structure. The novel catalyst can be easily recycled after reaction and reused many times with no significant loss of activity. The good stability can be attributed to the presence of isolated tungsten species anchored on the support through W{single bond}O{single bond}Si covalent bonds.
- Gao, Ruihua,Yang, Xinli,Dai, Wei-Lin,Le, Yingyi,Li, Hexing,Fan, Kangnian
-
p. 259 - 267
(2008/09/21)
-
- Synthesis of pendent functionalized cyclotriphosphazene polyoctenamers: Amphiphilic lithium ion conductive materials
-
The synthesis of novel polyoctenamers with pendent functionalized cyclotriphosphazenes as amphiphilic lithium ion conductive membranes is described. Cyclotriphosphazene monomers were functionalized with one cycloocteneoxy substituent per ring. Two different types of monomer units, one with oligoethyleneoxy cation coordination side groups and the other with hydrophobic fluoroalkoxy side groups, were then prepared. The syntheses of these monomers, their ring-opening metathesis copolymerization, and the characteristics of the resultant polymers are discussed, with an emphasis on the dependence of ionic conductivity and hydrophobicity on polymer composition.
- Allcock, Harry R.,Welna, Daniel T.,Stone, David A.
-
p. 10406 - 10412
(2008/02/01)
-
- Chemoselective epoxidation of dienes using polymer-supported manganese porphyrin catalysts
-
Manganese porphyrin catalysts supported on different polymer resins were assessed in the selective epoxidation of three dienes. The recyclability of the catalysts was examined.
- Brulé, Emile,De Miguel, Yolanda R.,Hii, King Kuok
-
p. 5913 - 5918
(2007/10/03)
-
- A tandem ring-closing metathesis cleavable linker system for solid-phase oligosaccharide synthesis
-
A novel triene linker system, that can be cleaved by a tandem ring-closing metathesis (RCM) reaction, is presented. The tandem RCM cleavage, that regenerates the active ruthenium catalyst without the need of additives like ethylene, proceeded very clean and fast to liberate cyclopent-2-enyl mannosides from the solid support. A cyclopent-2-enyl mannoside was isomerized to the corresponding vinyl ether glycoside, which could be readily deprotected by iodine-mediated hydrolysis.
- Timmer, Mattie S. M.,Codée, Jeroen D. C.,Overkleeft, Herman S.,Van Boom, Jacques H.,Van Der Marel, Gijsbert A.
-
p. 2155 - 2158
(2007/10/03)
-
- Environmentally friendly catalysis using supported reagents: Catalytic epoxidation with hydrogen peroxide mediated by iron(II) ions immobilised on γ-alumina
-
A simple heterogeneous catalyst based on supporting iron(II) ions on γ-alumina was developed and successfully applied to the selective epoxidation of olefins with 35% aqueous H2O2 as an oxygen donor in CH3CN.
- Monfared, Hassan Hosseini,Ghadimi, Mitra
-
p. 313 - 314
(2007/10/03)
-
- One-Pot and Stereospecific Synthesis of cis-1,2-Diazides via Mitsunobu Reaction of Epoxides
-
Mitsunobu reaction of epoxides using hydrazoic acid, diethylazodicarboxylate, and triphenylphosphine as reagents gave the corresponding cis-1,2-diazides in moderate yield. Application of similar reaction conditions to trans-diols furnished the corresponding trans-1,2-diazides.
- Goeksu, Sueleyman,Secen, Hasan,Suetbeyaz, Yasar
-
p. 2373 - 2378
(2007/10/03)
-
- Hydrogen perxide oxidation of hydrocarbons catalyzed by a silica supported iron precursor
-
Silica supported iron(II) was found to be an efficient catalyst for oxidation of hydrocarbons with hydrogen peroxide.
- Monfared,Ghorbani
-
p. 989 - 992
(2007/10/03)
-
- Methyltrioxorhenium-catalyzed epoxidations in ionic liquids
-
Alkenes and allylic alcohols have been epoxidized in an ambient- temperature ionic liquid for the first time using methyltrioxorhenium (MTO) and urea hydrogen peroxide; excellent conversions and selectivities for the epoxides of a wide number of substrates were observed.
- Owens, Gregory S.,Abu-Omar, Mahdi M.
-
p. 1165 - 1166
(2007/10/03)
-
- Synthesis of threo- and erythro-bis(2,2'-tetrahydrofuran). A novel serendipitous synthesis of a spiroketal
-
Racemic threo-bis(2,2'-tetrahydrofuran) and meso-erythro-bis(2,2'- tetrahydrofuran) have been prepared by stereochemically unambiguous routes. Treatment of 2-(1'-bromo-4'-hydroxybutyl)-tetrahydrofuran with base or silver(I) tetrafluoroborate effected cyclisation to 1,6-dioxa- spiro[4.5]decane.
- Kelly, David R.,Nally, James
-
p. 2209 - 2212
(2007/10/03)
-
- Design and synthesis of violet odorants with bicyclo[6.4.0]dodecene and bicyclo[5.4.0]undecene skeletons
-
The Diels-Alder reaction of 1,2-bis(methylene)cyclooctane (13), 4- methylenespiro[2.7]decane (29), 4-methylenespiro[2.6]nonane (40) and 4- methylenespiro[2.7]dec-8-ene (46) with different α,β-unsaturated carbonyl compounds afforded various derivatives 16, 18, 20, 22, 24, 26, 32, 36, 38, 41, 42 and 47 of a molecular-modeled lead compound 9. These less flexible β- ionone-mimics with bicyclo[6.4.0]dodecene and bicyclo[5.4.0]undecene skeletons possess interesting fruity-woody-floral odor notes and provide insight into the structure-odor correlation of violet odorants. 5-(2- Methylcycloalk-1-en-1-yl)hex-3-en-2-ones (e.g. 35) were identified as byproducts of the Rh(I)-catalyzed reactions of the vinylcyclopropanes 29 and 40.
- Kraft, Philip
-
p. 695 - 703
(2007/10/03)
-
- Double intramolecular S(N)' O-cyclization for stereoselective synthesis of bistetrahydrofuran core of acetogenins
-
A C2-symmetric bistetrahydrofuran core of acetogenins has been prepared via double intramolecular S(N)' O-cyclization reactions. Approaches using readily prepared both E- and Z-olefin substrates are investigated. The cyclization of E-olefins gave a mixture of two diastereomers with low selectivity, while the corresponding Z-olefins predominantly provided a desired trans,trans-bistetrahydrofuran product. The high diastereoselectivity is presumably controlled by a hydrogen-bonding transition state. An efficient enantioselective synthesis of this C2-symmetric bistetrahydrofuran is also described. Sharpless asymmetric dihydroxylation was used for this approach.
- Li, Pan,Yang, Jiong,Zhao, Kang
-
p. 2259 - 2263
(2007/10/03)
-
- Synthesis of optically active bicyclo[3.3.0]octane Skeleton using transannular reaction
-
Optically active 5-cyclooctene-1,2-diol derivatives prepared by an enzymatic procedure have been converted into bicyclo[3.3.0]octane derivatives by transannular reaction with complete inversion of the stereogenic center linked to the leaving group. Formal synthesis of (+)-iridomyrmecin has been achieved starting from (S,S)-5-cyclooctene-1,2-diol by using this process.
- Horikawa, Tamaki,Norimine, Yoshihiko,Tanaka, Masakazu,Sakai, Kiyoshi,Suemune, Hiroshi
-
-
- Ring-fused and spiro cyclopentenones by Ni(CO)4-promoted intermolecular carbonylative cycloaddition of acetylenes with 3-halo- and 1-(halomethyl)cycloalkenes
-
The title carbonylative cycloaddition of five- to eight-member ring 3-halo- and 1-(halomethyl)cycloalkenes with different acetylenes was studied. From moderate to good yields of ring-fused and spiro cyclopentenone derivatives were obtained, especially in the reaction with acetylenes bearing electron-withdrawing substituents by proper selection of the reaction conditions to avoid the acetylene polyinsertion and/or other side reactions from the organonickel intermediates. In this context, the beneficial role of acetate ion on the outcome of the reaction is rationalized. This process leading to the formation of bicycloadducts with the concomitant formation of up to six C-C bonds, with high regio- and stereoselectivity, can be useful in the synthesis of natural products as exemplified by the easy preparation of [5-5-5] tricyclic compound 14 from a 1:1 cis and trans isomeric mixture of 6-acetoxy-3-bromocyclooctene (11). A plausible general reaction mechanism is proposed that is consistent with all the products obtained.
- Pagès, Lluís,Llebaria, Amadeu,Camps, Francisco,Molins, Elies,Miravitlles, Caries,Moretó, Josep M.
-
p. 10449 - 10461
(2007/10/02)
-
- Transition-Metal Phthalocyanins as Catalysts for Alkene Epoxidation
-
The epoxidation of alkenes catalyzed by transition-metal phthalocyanins has been studied.All the transition-metal phthalocyanins studied have catalytic properties: the manganese and iron phthalocyanins are most effective when iodosylbenzene is the oxygen donor, whereas cobalt and nickel phthalocyanins are best under phase-transfer catalysis conditions with sodium hypochlorite as the oxygen donor.The epoxidation of cis-alkenes leads to a mixture of cis- and trans-epoxides; the presence of 2,6-di-tert-butyl-p-cresol in the iron(II) phthalocyanin-catalysed reaction leads to a highly stereospecific epoxidation of cis-alkenes.The results are discussed in relation to other transition-metal-catalyzed epoxidations.
- Larsen, Erik,Joergensen, Karl Anker
-
p. 259 - 263
(2007/10/02)
-
- SODIUM PERBORATE OXIDATIONS OF CYCLIC AND ACYCLIC ALKENES TO OXIRANES OR VICINAL ACETOXY ALCOHOLS
-
Under different reaction conditions, sodium perborate/acetic anhydride oxidizes alkenes into oxiranes or vicinal acetoxy alcohols in good yields.
- Xie, Gaoyang,Xu, Linxiao,Hu, Jun,Ma, Shiming,Hou, Wei,Tao, Fenggang
-
p. 2967 - 2968
(2007/10/02)
-
- Synthesis of 9-Oxabicyclonon-3-yne
-
Starting with 1,5-cyclooctadiene (1), the title compound 9 is gained in a synthesis of seven steps. 9 exists in two conformations 9a and 9b, of which 9a shows a strong interaction between the oxygen atom and the strained triple bond.Thermal fragmentation of the 1,2,3-selenadiazole 7 is used for the introduction of the triple bond.The structural proof of 7 is performed by 2D-NMR spectroscopy.
- Meier, Herbert,Mayer, Winfried,Kolshorn, Heinz
-
p. 685 - 690
(2007/10/02)
-
- Biosynthesic Studies of Marine Lipids. 11. Synthesis, Biosynthesis, and Absolute Configuration of the Internally Branched Demospongic Acid, 22-Methyl-5,9-octacosadienoic Acid
-
The 14C-labeled short-chain fatty acid 10-methylhexadecanoic acid (10-Me-16:0) as well as its hitherto undescribed 10R and 10S antipodes was incorporated into the marine sponge Aplysina fistularis and transformed in situ into 22-methyl-5,9-octacosadienoic acid (22-Me-Δ5,9-28:2) by chain elongation.No qualitative specificity between the two enantiomers was observed. Methionine was also incorporated into the sponge to investigate the methylation process; a rapid incorporation into the short branched fatty acids occurred with subsequent chain elongation.Both enantiomers were synthesized starting from (+)-pulegone to determine the absolute configuration of the 22-methyl-5,9-octacosadienoic (22-Me-Δ5,9-28:2) acid.The naturally occurring acid has the 22R configuration.
- Raederstorff, Daniel,Shu, Arthur Y.L.,Thompson, Janice E.,Djerassi, Carl
-
p. 2337 - 2346
(2007/10/02)
-
- LIQUID PHASE OXIDATION OF CYCLIC POLYOLEFINS WITH MOLECULAR OXYGEN. PART II. CIS,CIS-1,5-CYCLOOCTADIENE AUTOOXIDATION
-
The autooxidation of 1,5-cyclooctadiene has been studied.Cyclooctadiene easily undergoes oxidation by molecular oxygen.Depending on the reaction procedure and the degree of conversion, polymeric or monomeric oxidated products are the dominating products with the preservation of eight-membered ring.The content of 1,2-epoxycyclooctene-5 in the product may exceed 50percent.The reaction was found to be of a free-radical character.An initiation and propagation scheme of the autooxidation is proposed.
- Giezynski, Roman,Pala, Magdalena
-
-
- Synthesis of Cyclic Ethers via Bromine Assisted Epoxide Ring Expansion
-
Neighbouring group participation by epoxide oxygen in the opening of bromonium ions results in the stereoselective synthesis of cyclic ethers. 9-Oxabicyclonon-4-ene gives trans, trans-2,6-dibromo-9-oxabicyclononane and trans,trans-2,5-dibromo-9-oxabicyclononane.Sequential bromination and Bu3SnH reduction converts 1,2-epoxyhex-5-ene into cis- and trans-2,5-dimethyltetrahydrofuran and 2-methyltetrahydropyran while (+)-cis-limonene oxide is converted into non-chiral cineole.
- Davies, Stephen G.,Polywka, Mario E. C.,Thomas, Susan E.
-
p. 1277 - 1282
(2007/10/02)
-
- Reactions of Iodine(I) Acetate with Alkenes and Vicinal Diols
-
The chemoselectivities of the reactions of iodine(I) acetate and iodine(I) acetate-thallium(I) acetate with cis-cyclooct-5-ene-1,2-diol have been investigated.The addition of iodine(I) acetate to cyclo-octa-1,5-diene, for a number of reagent systems, results in products arising from both 1,2-addition and transannular pathways.
- Cambie, Richard C.,Rutledge, Peter S.,Stewart, Georgina M.,Woodgate, Paul D.,Woodgate, Sheila D.
-
p. 1689 - 1698
(2007/10/02)
-
- LIQUID PHASE OXIDATION OF CYCLIC POLYOLEFINS WITH MOLECULAR OXYGEN. PART I. CIS,CIS-1,5-CYCLOOCTADIENE OXIDATION REACTION PRODUCTS
-
The products of liquid-phase of 1,5-cyclooctadiene with molecular oxygen were isolated and identified.
- Giezynski, Roman,Pala, Magdalena
-
p. 1349 - 1355
(2007/10/02)
-
- Oxymetallation. Part 13. Synthesis of Bicyclic Peroxides via Peroxymercuriation of Cyclic Dienes
-
The bis-mercuriated derivative (12) of 9,10-dioxabicyclodecane has been prepared by peroxymercuriation of cis,cis-octa-1,5-diene, but substantial amounts of bicyclic ethers are also formed in the reaction.The bicyclic peroxides (4) and (5) have been obtained from (12) by reduction and brominolysis respectively. 8,9-Dioxabicyclodecane (6) and the dibromo-derivative (7) have similarly been prepared by peroxymercuriation and demercuriation of cyclo-octa-1,4-diene.It is suggested that the isomeric purity of the peroxides and the concurrent formation of bicyclic ethers both result from equilibrium control of reversible (per)oxymercuriation-de(per)oxymercuriation.A low yield of the -peroxide (8) has been obtained by peroxymercuriation and brominolysis of cyclohexa-1,4-diene, but attempts to prepare -compounds from 5,5-disubstituted cyclopentadienes have been unsuccessful.
- Bloodworth, A.J.,Khan, Jamil A.,Loveitt, M.E.
-
p. 621 - 632
(2007/10/02)
-
- Studies on the Autoxidation of Some Monocyclic Olefins
-
The autoxidations of cyclopentene, cyclohexene, cycloheptene, cyclooctene, cycloocta-1,5-diene, 1-methylcyclopentene, 1-methylcyclohexene, 1-methylcycloheptene, 1-methylcyclooctene, methylene cyclopentene, and methylene cyclohexene with pure oxygen under normal pressure were studied.The epoxides formed were determined gaschromatographically.In most cases also the products of allylic oxidation were analyzed and their structures elucidated after reduction to the corresponding allyl alcohols.The portions of high boiling or polymeric products which could not be detected gaschromatographically and also the real yields of epoxides were determined by balance experiments in the presence of inert internal standards.
- Blau, K.,Mueller, U.,Pritzkow, W.,Schmidt-Renner, W.,Sedshaw, Z.
-
p. 915 - 932
(2007/10/02)
-