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You searched for: Subject term epoxides Remove constraint Subject term: epoxides Subject term catalytic activity Remove constraint Subject term: catalytic activity
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1. Asymmetric base-mediated epoxide isomerisation

Author:
Angelika Magnus; Sophie K. Bertilsson; Pher G. Andersson
Source:
Chemical Society reviews 2002 v.31 no.4 pp. 223-229
ISSN:
1460-4744
Subject:
alcohols; catalytic activity; enantioselectivity; epoxides; isomerization
Abstract:
... The base-mediated rearrangement of epoxides into allylic alcohols is a well-known synthetic transformation. The first enantioselective version of the reaction using a chiral base was reported in 1980. Since then, the reaction has received a lot of attention mostly due to the great usefulness of chiral allylic alcohols in organic synthesis. Major breakthroughs in the area were the first report on u ...
DOI:
10.1039/b104372m

2. Electrochemical activation of carbon dioxide in ionic liquid: synthesis of cyclic carbonates at mild reaction conditions

Author:
Hongzhou Yang; Yanlong Gu; Youquan Deng; Feng Shi
Source:
Chemical communications 2002 v. no.3 pp. 274-275
ISSN:
1364-548X
Subject:
ambient temperature; carbon dioxide; carbonates; catalysts; catalytic activity; cycloaddition reactions; electrochemistry; electrolytes; epoxides; ionic liquids
Abstract:
... Electrocatalytic cycloaddition of carbon dioxide to epoxides in room temperature ionic liquids as reaction media without any additional supporting electrolyte and catalyst could be conducted with high to excellent performances under mild conditions. ...
DOI:
10.1039/b108451h

3. Synthesis of epoxides from aldehydes and tosylhydrazone salts catalysed by triphenylarsine: complete trans selectivity for all combinations of coupling partners

Author:
Varinder K. Aggarwal; Mamta Patel; John Studley
Source:
Chemical communications 2002 v. no.14 pp. 1514-1515
ISSN:
1364-548X
Subject:
aldehydes; carbonyl compounds; catalytic activity; chemical reactions; epoxides; salts
Abstract:
... Triphenylarsine catalyses the formation of epoxides from carbonyl compounds and tosylhydrazone salts. This convergent synthesis gives complete trans selectivity for all aldehyde and tosylhydrazone salt coupling partners. ...
DOI:
10.1039/b204252e

4. [Cr(Salen)] as a ‘bridge’ between asymmetric catalysis, Lewis acids and redox processes

Author:
Marco Bandini; Pier Giorgio Cozzi; Achille Umani-Ronchi
Source:
Chemical communications 2002 v. no.9 pp. 919-927
ISSN:
1364-548X
Subject:
Lewis acids; catalytic activity; chromium; cycloaddition reactions; epoxides; organic chemistry
Abstract:
... An overview focused on the synthesis, structural features and catalytic applications of chiral [Cr(Salen)] complexes is presented. Key aspects of modern organic chemistry such as Lewis acids, asymmetric catalysis and redox processes are strictly connected with chromium–Schiff base complexes. Among the asymmetric transformations mediated by [Cr(Salen)] complexes, Diels–Alder and hetero-Diels–Alder ...
DOI:
10.1039/b109945k

5. Cetylpyridinium dodecatungstate on fluorapatite: efficient and reusable solid catalyst for solvent-free epoxidation

Author:
Junko Ichihara; Akihiro Kambara; Katsuma Iteya; Eiko Sugimoto; Takeshi Shinkawa; Aki Takaoka; Shunro Yamaguchi; Yoh Sasaki
Source:
Green chemistry 2003 v.5 no.5 pp. 491-493
ISSN:
1463-9270
Subject:
alcohols; alkenes; ambient temperature; apatite; catalysts; catalytic activity; cetylpyridinium chloride; epoxidation reactions; epoxides; green chemistry; solvents
Abstract:
... We have developed a new catalytic solid phase system for epoxidations using urea–hydrogen peroxide complex (urea–H₂O₂) and cetylpyridinium dodecatungstate ((CetylPy)₁₀ [H₂W₁₂O₄₂]) catalyst on fluorapatite. In the solid phase system epoxidations of cyclic alkenes and allylic alcohols proceeded without solvent at room temperature to afford the corresponding epoxides in good yields. The recovered sol ...
DOI:
10.1039/b303315e

6. Chiral Co(iii)(salen)-catalysed hydrolytic kinetic resolution of racemic epoxides in ionic liquids

Author:
Chun Rim Oh; Dong Joon Choo; Woo Ho Shim; Dong Hoon Lee; Eun Joo Roh; Sang-gi Lee; Choong Eui Song
Source:
Chemical communications 2003 v. no.9 pp. 1100-1101
ISSN:
1364-548X
Subject:
acetic acid; catalysts; catalytic activity; cobalt; epoxides; ionic liquids; oxidation
Abstract:
... In the chiral Co(iii)(salen)-catalysed HKR of racemic epoxides, in the presence of ionic liquids, Co(ii)(salen) complex is oxidised without acetic acid to catalytically active Co(iii)(salen) complex during reaction and, moreover, this oxidation state is stabilised against reduction to Co(ii) complex which enables the reuse of the recovered catalyst for consecutive reactions without extra reoxidati ...
DOI:
10.1039/b301490h

7. Environmentally benign, sequential synthesis of 3,4-dihydro-2H-1,4-benzoxazines under phase transfer catalysis conditions

Author:
Domenico Albanese; Andrea Donghi; Dario Landini; Vittoria Lupi; Michele Penso
Source:
Green chemistry 2003 v.5 no.4 pp. 367-369
ISSN:
1463-9270
Subject:
catalytic activity; epoxides; green chemistry; sodium hydroxide
Abstract:
... An environmentally friendly synthesis of 2-substituted 3,4-dihydro-2H-1,4-benzoxazines has been carried out in a sequential fashion through the R₄N⁺F⁻ catalyzed ring opening of epoxides with arylsulfonamides, followed by in situ cyclization of the hydroxysulfonamides thus obtained with NaOH aq. and n-C₁₄H₂₉N⁺Me₃Cl⁻. ...
DOI:
10.1039/b304095j

8. Polyoxometalate-catalysed epoxidation of 1-octene with hydrogen peroxide in microemulsions coupled with ultrafiltration

Author:
Arnold Lambert; Pawel Plucinski; Ivan V. Kozhevnikov
Source:
Chemical communications 2003 v. no.6 pp. 714-715
ISSN:
1364-548X
Subject:
catalytic activity; emulsions; epoxidation reactions; epoxides; hydrogen peroxide; salts; ultrafiltration
Abstract:
... Epoxidation of 1-octene with hydrogen peroxide catalysed by amphiphilic salts of peroxo tungstophosphate {PO₄[WO(O₂)₂]₄}³⁻ in water-in-oil microemulsions is an efficient and environmentally benign reaction which, coupled with ultrafiltration, shows the potential for continuous production of epoxides. ...
DOI:
10.1039/b300494p

9. The first example of enantioselective isocyanosilylation of meso epoxides with TMSCN catalyzed by novel chiral organogallium and indium complexes

Author:
Chengjian Zhu; Fang Yuan; Weijin Gu; Yi Pan
Source:
Chemical communications 2003 v. no.6 pp. 692-693
ISSN:
1364-548X
Subject:
catalytic activity; chemical reactions; cyanides; enantioselectivity; epoxides; indium; ligands; organosilicon compounds
Abstract:
... The desymmetrization ring opening of meso epoxides using trimethylsilyl cyanide catalyzed by organogallium and indium complexes with binaphthol monoether derivatives as chiral ligands gave β-isocyanohydrins with moderate to excellent enantioselectivities of up to 95% ee. ...
DOI:
10.1039/b212511k

10. A novel palladium-catalyzed coupling of epoxides with allyl bromide mediated by indium(i) chloride: a cascade epoxide rearrangement–carbonyl allylation

Author:
Nan Jiang; Qingyuan Hu; Carrolyn S. Reid; Yunfeng Lu; Chao-Jun Li
Source:
Chemical communications 2003 v. no.18 pp. 2318-2319
ISSN:
1364-548X
Subject:
allylation; catalysts; catalytic activity; epoxides; indium; organobromine compounds; palladium; porous media; silica
Abstract:
... A cascade epoxide rearrangement–aldehyde allylation was developed by using a combination of InCl and reusable heterogeneous mesoporous silica supported palladium catalysts. ...
DOI:
10.1039/b305161g

11. Development of porous materials for heterogeneous catalysis: kinetic resolution of epoxides

Author:
Leilani L. Welbes; Robert C. ScarrowDepartment of Chemistry, Haverford College, Haverford, PA 19041, USA.; A. S. Borovik
Source:
Chemical communications 2004 v. no.22 pp. 2544-2545
ISSN:
1364-548X
Subject:
catalytic activity; cobalt; copolymerization; epoxides; porous media
Abstract:
... Template copolymerization methods have been utilized to prepare porous materials with immobilized cobalt complexes that catalyze the hydrolytic kinetic resolution of epoxides. ...
DOI:
10.1039/b408553a

12. Enantioselective epoxidation of olefins with chiral metalloporphyrin catalysts

Author:
Eric Rose; Bruno Andrioletti; Samia Zrig; Mélanie Quelquejeu-Ethève
Source:
Chemical Society reviews 2005 v.34 no.7 pp. 573-583
ISSN:
1460-4744
Subject:
alcohols; alkenes; biomimetics; catalysts; catalytic activity; enantioselectivity; epoxidation reactions; epoxides; iron; manganese; oxidants; porphyrins; styrene; temperature; titanium
Abstract:
... The intent of this tutorial review is to cover the recent progress accomplished in iron and manganese porphyrin-catalyzed enantioselective epoxidation of terminal olefins. The literature is covered up to the beginning of 2005. In the first part of the manuscript, we will present the results obtained with simple catalysts in the early eighties, before describing the pickets and strapped series repo ...
DOI:
10.1039/b405679p

13. Tertiary amines as highly efficient catalysts in the ring-opening reactions of epoxides with amines or thiols in H₂O: expeditious approach to β-amino alcohols and β-aminothioethers

Author:
Jie Wu; Hong-Guang Xia
Source:
Green chemistry 2005 v.7 no.10 pp. 708-710
ISSN:
1463-9270
Subject:
amino alcohols; catalysts; catalytic activity; epoxides; green chemistry; thiols; triethylamine
Abstract:
... Ring-opening of epoxides with various amines or thiols catalyzed by DABCO (1,4-diazabicyclic[2,2,2]octane) or Et₃N (1 mol%) in water afforded the corresponding products in good to excellent yields under mild reaction conditions. ...
DOI:
10.1039/b509288d

14. A single-site hydroxyapatite-bound zinc catalyst for highly efficient chemical fixation of carbon dioxide with epoxides

Author:
Kohsuke Mori; Yohei Mitani; Takayoshi Hara; Tomoo Mizugaki; Kohki Ebitani; Kiyotomi Kaneda
Source:
Chemical communications 2005 v. no.26 pp. 3331-3333
ISSN:
1364-548X
Subject:
Lewis bases; carbon dioxide; catalysts; catalytic activity; chemical reactions; epoxides; hydroxyapatite; solvents; zinc
Abstract:
... A zinc-based hydroxyapatite catalyst in conjunction with a Lewis base proved to be efficient for the coupling of CO₂ and epoxide in the absence of additional organic solvents under an atmospheric CO₂ pressure; the work-up procedure is straightforward and the catalyst could be reused without loss of catalytic activity and selectivity. ...
DOI:
10.1039/b502636a

15. Diversity and Biocatalytic Potential of Epoxide Hydrolases Identified by Genome Analysis

Author:
Loo, Bert van; Kingma, Jaap; Arand, Michael; Wubbolts, Marcel G.; Janssen, Dick B.
Source:
Applied and environmental microbiology 2006 v.72 no.4 pp. 2905-2917
ISSN:
0099-2240
Subject:
Actinobacteria; Escherichia coli; binding proteins; biodegradation; catalytic activity; databases; epoxide hydrolase; epoxides; fungi; genes; genomics; inclusion bodies; males; molecular cloning; sequence alignment
Abstract:
... Epoxide hydrolases play an important role in the biodegradation of organic compounds and are potentially useful in enantioselective biocatalysis. An analysis of various genomic databases revealed that about 20% of sequenced organisms contain one or more putative epoxide hydrolase genes. They were found in all domains of life, and many fungi and actinobacteria contain several putative epoxide hydro ...
DOI:
10.1128/AEM.72.4.2905-2917.2006
PubMed:
16597997
PubMed Central:
PMC1448995

16. New directions for the Morita−Baylis–Hillman reaction; homologous aldol adducts via epoxide opening

Author:
Marie E. Krafft; James A. Wright
Source:
Chemical communications 2006 v. no.28 pp. 2977-2979
ISSN:
1364-548X
Subject:
catalytic activity; chemical reactions; epoxides
Abstract:
... Under trialkylphosphine catalyzed Morita–Baylis–Hillman reaction conditions, epoxides react with enones to give rise to homologous aldol adducts. ...
DOI:
10.1039/b603510h

17. Effect of ionic liquids on epoxide hydrolase-catalyzed synthesis of chiral 1,2-diols

Author:
Cinzia Chiappe; Elsa Leandri; Bruce D. Hammock; Christophe Morisseau
Source:
Green chemistry 2007 v.9 no.2 pp. 162-168
ISSN:
1463-9270
Subject:
catalytic activity; enantioselectivity; epoxide hydrolase; epoxides; ethylene oxide; green chemistry; hydrolysis; ionic liquids; mice; rats; solubility
Abstract:
... Ionic liquids (ILs) offer new possibilities for epoxide hydrolase (EH) catalyzed resolution of epoxides and for synthesis of chiral 1,2-diols. Soluble EHs from cress and mouse (csEH and msEH) and microsomal EH from rat (rmEH) were tested in several ILs. For all the enzymes tested, higher enantioselectivities were obtained in [bmim][N(Tf)₂] and [bmim][PF₆]. The optimized amount of water for EH acti ...
DOI:
10.1039/b612106c
PubMed:
18160974
PubMed Central:
PMC2153531

18. Palladium nanoparticles-catalyzed regio- and chemoselective hydrogenolysis of benzylic epoxides in water

Author:
Emilie Thiery; Jean Le Bras; Jacques Muzart
Source:
Green chemistry 2007 v.9 no.4 pp. 326-327
ISSN:
1463-9270
Subject:
alcohols; catalysts; catalytic activity; chemoselectivity; epoxides; green chemistry; nanoparticles; palladium
Abstract:
... Hydrogenolysis of various benzylic epoxides was achieved in water to give alcohols in 51–98% yield using recyclable Pd nanoparticles as catalyst. ...
DOI:
10.1039/b616486b

19. Supported choline chloride/urea as a heterogeneous catalyst for chemical fixation of carbon dioxide to cyclic carbonates

Author:
Anlian Zhu; Tao Jiang; Buxing Han; Jicheng Zhang; Ye Xie; Xiumin Ma
Source:
Green chemistry 2007 v.9 no.2 pp. 169-172
ISSN:
1463-9270
Subject:
biodegradability; carbon dioxide; carbonates; catalysts; catalytic activity; choline chloride; epoxides; green chemistry; ionic liquids; reaction mechanisms; sieves; synergism; urea
Abstract:
... In this work, the catalytic efficiency of ionic liquid (IL) choline chloride/urea supported on molecular sieves for the reactions of CO₂ and epoxides was studied under different conditions. It was demonstrated that this biodegradable and green catalyst is very active and selective, and choline chloride and urea showed a synergetic effect in promoting these reactions. After reaction, the solid cata ...
DOI:
10.1039/b612164k

20. Epoxy functionalised poly(ε-caprolactone): synthesis and application

Author:
Jiaxiang Zhou; Wenxin Wang; Silvia Villarroya; Kristofer J. Thurecht; Steven M. Howdle
Source:
Chemical communications 2008 v. no.44 pp. 5806-5808
ISSN:
1364-548X
Subject:
anhydrides; carbon dioxide; carboxylic ester hydrolases; catalytic activity; composite polymers; epoxides; glycidol; lactones; polymerization
Abstract:
... Glycidol is used as an initiator for ring-opening polymerisation of ε-caprolactone (ε-CL) to synthesise epoxy-functionalised poly(ε-caprolactone) (PCL) in a reaction catalysed by lipase, and the epoxy-functionalised PCL was further copolymerised with carbon dioxide or anhydride to produce novel graft or hyperbranched copolymers. ...
DOI:
10.1039/b810297j