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Ibrahem, Ismail
Publications (10 of 22) Show all publications
Cordova, A., Afewerki, S., Alimohammadzadeh, R., Sanhueza, I., Tai, C.-W., Osong, S. H., . . . Ibrahem, I. (2019). A sustainable strategy for production and functionalization of nanocelluloses. Pure and Applied Chemistry, 91(5), 865-874
Open this publication in new window or tab >>A sustainable strategy for production and functionalization of nanocelluloses
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2019 (English)In: Pure and Applied Chemistry, ISSN 0033-4545, E-ISSN 1365-3075, Vol. 91, no 5, p. 865-874Article in journal (Refereed) Published
Abstract [en]

A sustainable strategy for the neat production and surface functionalization of nanocellulose from wood pulp is disclosed. It is based on the combination of organocatalysis and click chemistry ("organoclick" chemistry) and starts with nanocellulose production by organic acid catalyzed hydrolysis and esterification of the pulp under neat conditions followed by homogenization. This nanocellulose fabrication route is scalable, reduces energy consumption and the organic acid can be efficiently recycled. Next, the surface is catalytically engineered by "organoclick" chemistry, which allows for selective and versatile attachment of different organic molecules (e.g. fluorescent probes, catalyst and pharmaceuticals). It also enables binding of metal ions and nanoparticles. This was exemplified by the fabrication of a heterogeneous nanocellulose-palladium nanoparticle catalyst, which is used for Suzuki cross-coupling transformations in water. The disclosed surface functionalization methodology is broad in scope and applicable to different nanocelluloses and cellulose based materials as well.

Keywords
click chemistry, cross-coupling reaction, heterogeneous catalysis, nanocellulose, NICE-2016, organocatalysis, surface engineering
National Category
Chemical Engineering
Identifiers
urn:nbn:se:miun:diva-35142 (URN)10.1515/pac-2018-0204 (DOI)000466859500008 ()2-s2.0-85056591870 (Scopus ID)
Available from: 2018-12-10 Created: 2018-12-10 Last updated: 2020-01-21Bibliographically approved
Ibrahem, I., Iqbal, M. N., Verho, O., Eivazihollagh, A., Olsén, P., Edlund, H., . . . Johnston, E. V. (2018). Copper Nanoparticles on Controlled Pore Glass and TEMPO for the Aerobic Oxidation of Alcohols. ChemNanoMat, 4(1), 71-75
Open this publication in new window or tab >>Copper Nanoparticles on Controlled Pore Glass and TEMPO for the Aerobic Oxidation of Alcohols
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2018 (English)In: ChemNanoMat, ISSN 2199-692X, Vol. 4, no 1, p. 71-75Article in journal (Refereed) Published
Abstract [en]

Herein, we report on the facile synthesis of a heterogeneous copper nanocatalyst and its combination with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) for the aerobic oxidation of alcohols to their corresponding carbonyl compounds. This low cost copper nanocatalyst was found to exhibit excellent recyclability, making it a highly attractive catalytic system from an economical and environmental point of view. Extensive characterization of the catalyst by a number of techniques revealed that it was comprised of well-dispersed Cu(I/II) nanoparticles with an average size of around 6nm.

Keywords
Alcohol oxidation, Copper nanoparticles, Green chemistry, Heterogeneous catalysis, TEMPO
National Category
Chemical Sciences
Identifiers
urn:nbn:se:miun:diva-32328 (URN)10.1002/cnma.201700309 (DOI)000419237800011 ()2-s2.0-85033664510 (Scopus ID)
Note

Version of record online: 14 November 2017

Available from: 2017-12-07 Created: 2017-12-07 Last updated: 2019-08-06Bibliographically approved
Eivazihollagh, A., Bäckström, J., Dahlström, C., Carlsson, F., Ibrahem, I., Lindman, B., . . . Norgren, M. (2017). One-pot synthesis of cellulose-templated copper nanoparticles with antibacterial properties. Materials letters (General ed.), 187, 170-172
Open this publication in new window or tab >>One-pot synthesis of cellulose-templated copper nanoparticles with antibacterial properties
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2017 (English)In: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 187, p. 170-172Article in journal (Refereed) Published
Abstract [en]

We report a facile in situ synthesis of spherical copper nanoparticles (NPs) templated by a gelled cellulose II matrix under alkaline aqueous reaction conditions. In under 20 min, the hybrid material could be obtained in a one-pot reaction. Field-emission scanning electron microscopy (FE-SEM) revealed that the polycrystalline NPs of 200–500 nm were well distributed in the regenerated cellulose matrix. The average Cu crystallite size was of the order of 20 nm, as estimated from both X-ray diffraction (XRD) and FE-SEM. XRD data also indicated that the composite contained up to approximately 20% Cu2O. In suspensions containing the hybrid material, growth of Escerichia coli and Staphylococcus aureus strains was inhibited by 80% and 95%, respectively, after 72 h. The synthesis procedure offers a general approach to designing various low-cost hybrid materials of almost any shape, and the concept could be extended to utilization areas such as catalysis, functional textiles, and food packaging as well as to electronic applications.

Keywords
One-pot synthesis, Copper nanoparticles, Cellulose, Hybrid material, Antibacterial properties
National Category
Nano Technology Chemical Engineering Composite Science and Engineering
Identifiers
urn:nbn:se:miun:diva-29336 (URN)10.1016/j.matlet.2016.10.026 (DOI)000390628200045 ()2-s2.0-84994876232 (Scopus ID)FSCN (Local ID)FSCN (Archive number)FSCN (OAI)
Projects
NovoCell - Novel use of native cellulose in dispersions and functional biocomposites
Funder
Swedish Research Council Formas, 942-2015-251
Available from: 2016-11-24 Created: 2016-11-24 Last updated: 2018-06-28Bibliographically approved
Afewerki, S., Ma, G., Ibrahem, I., Liu, L., Sun, J. & Cordova, A. (2015). Highly Enantioselective Control of Dynamic Cascade Transformations by Dual Catalysis: Asymmetric Synthesis of Polysubstituted Spirocyclic Oxindoles. ACS Catalysis, 5(2), 1266-1272
Open this publication in new window or tab >>Highly Enantioselective Control of Dynamic Cascade Transformations by Dual Catalysis: Asymmetric Synthesis of Polysubstituted Spirocyclic Oxindoles
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2015 (English)In: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 5, no 2, p. 1266-1272Article in journal (Refereed) Published
Abstract [en]

The highly enantioselective (up to >99.5:0.5 er) synthesis of polysubstituted spirocyclic oxindoles with four new contiguous stereocenters, including the spiro all-carbon quaternary center, is disclosed. It is accomplished by the highly stereoselective control of a dynamic conjugate/intramolecular allylic alkylation relay sequence based on the synergistic cooperation of metal and chiral amine catalysts in which the careful selection of organic Nand, metal complex, and chiral amine is essential. The intermolecular C-C bond-forming step occurred only when both the metal and chiral amine catalysts were present.

Keywords
all-carbon quaternary stereocenter, asymmetric cocatalysis, dynamic transformations, polysubstituted, spirocyclic oxindoles, α, β-unsaturated aldehydes
National Category
Chemical Sciences
Identifiers
urn:nbn:se:miun:diva-24590 (URN)10.1021/cs501975u (DOI)000349275300086 ()2-s2.0-84922713231 (Scopus ID)
Available from: 2015-03-17 Created: 2015-03-17 Last updated: 2017-12-04Bibliographically approved
Duan, R., Ibrahem, I., Edlund, H. & Norgren, M. (2014). Acid-Catalyzed Synthesis of Foamed Materials from Renewable Sources. Industrial & Engineering Chemistry Research, 53(45), 17597-17603
Open this publication in new window or tab >>Acid-Catalyzed Synthesis of Foamed Materials from Renewable Sources
2014 (English)In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 53, no 45, p. 17597-17603Article in journal (Refereed) Published
Abstract [en]

In this study, lightweight biobased foamed materials were successfully synthesized by the modification of renewable polysaccharides, such as starch and microcrystalline cellulose. Low-cost and nontoxic organic acids were utilized as catalysts in the first-step esterification reaction of the synthesis. The effects of different reaction conditions on the water absorbency and weight loss of freeze-casted polysaccharide–citrate–chitosan foams are discussed. Physical properties, such as pore-size distributions and compressive stress–strain curves, of the foams were determined. The characterization results show that the amide bonds formed between the carboxylic acid groups of polysaccharide–citrate and the amino groups of chitosan are crucial to the foamed material’s performance.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2014
National Category
Chemical Process Engineering
Identifiers
urn:nbn:se:miun:diva-23772 (URN)10.1021/ie501169w (DOI)000344906400009 ()2-s2.0-84910128893 (Scopus ID)
Projects
FORE
Available from: 2014-12-15 Created: 2014-12-15 Last updated: 2017-12-05Bibliographically approved
Afewerki, S., Guangning, M., Ibrahem, I. & Cordova, A. (2014). Highly enantioselective organo/metal cooperative catalysis for construction of spirocyclopentaneoxindoles. Paper presented at 248th National Meeting of the American-Chemical-Society (ACS), AUG 10-14, 2014, San Francisco, CA. Abstract of Papers of the American Chemical Society, 248, Article ID 173-ORGN.
Open this publication in new window or tab >>Highly enantioselective organo/metal cooperative catalysis for construction of spirocyclopentaneoxindoles
2014 (English)In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 248, article id 173-ORGNArticle in journal, Meeting abstract (Other academic) Published
National Category
Chemical Sciences
Identifiers
urn:nbn:se:miun:diva-24667 (URN)000349167402638 ()
Conference
248th National Meeting of the American-Chemical-Society (ACS), AUG 10-14, 2014, San Francisco, CA
Available from: 2015-08-28 Created: 2015-03-20 Last updated: 2017-12-04Bibliographically approved
Ma, G., Afewerki, S., Deiana, L., Palo-Nieto, C., Liu, L., Sun, J., . . . Córdova, A. (2013). A palladium/chiral amine co-catalyzed enantioselective dynamic cascade reaction: Synthesis of polysubstituted carbocycles with a quaternary carbon stereocenter. Angewandte Chemie International Edition, 52(23), 6050-6054
Open this publication in new window or tab >>A palladium/chiral amine co-catalyzed enantioselective dynamic cascade reaction: Synthesis of polysubstituted carbocycles with a quaternary carbon stereocenter
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2013 (English)In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, no 23, p. 6050-6054Article in journal (Refereed) Published
Abstract [en]

Polysubstituted 5- and 6-membered carbocycles were synthesized by the title reaction. The one-pot dynamic relay process generates four new stereocenters, including a quaternary carbon center, in a highly enantioselective fashion (99.5:0.5→99:0.5 e.r.) by using a simple combination of palladium and chiral amine co-catalysts. 

Keywords
aldehydes, asymmetric catalysis, carbocycles, co-catalysis, quaternary carbon stereocenters
National Category
Organic Chemistry
Identifiers
urn:nbn:se:miun:diva-19359 (URN)10.1002/anie.201300559 (DOI)000319742400028 ()2-s2.0-84878387915 (Scopus ID)
Note

:doi 10.1002/anie.201300559

Available from: 2013-09-05 Created: 2013-06-19 Last updated: 2017-12-06Bibliographically approved
Duan, R., Norgren, M., Hedenström, E., Ibrahem, I. & Edlund, H. (2013). New approaches toward producing foamed materials from renewable sources.. In: : . Paper presented at The 17th International Symposiumon Wood, Fiber and Pulping Chemistry, June 12-14, 2013, Canada.
Open this publication in new window or tab >>New approaches toward producing foamed materials from renewable sources.
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2013 (English)Conference paper, Oral presentation with published abstract (Refereed)
National Category
Chemical Engineering
Identifiers
urn:nbn:se:miun:diva-20749 (URN)
Conference
The 17th International Symposiumon Wood, Fiber and Pulping Chemistry, June 12-14, 2013, Canada
Available from: 2013-12-17 Created: 2013-12-17 Last updated: 2016-09-29Bibliographically approved
Ibrahem, I., Ma, G., Afewerki, S. & Córdova, A. (2013). Palladium/Chiral Amine Co-catalyzed Enantioselective beta-Arylation of alpha,beta-Unsaturated Aldehydes. Angewandte Chemie International Edition, 52(3), 878-882
Open this publication in new window or tab >>Palladium/Chiral Amine Co-catalyzed Enantioselective beta-Arylation of alpha,beta-Unsaturated Aldehydes
2013 (English)In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, no 3, p. 878-882Article in journal (Refereed) Published
Abstract [en]

Palladium and a simple chiral amine are used as co-catalysts for the enantioselective conjugate addition of aryl boronic acids to α,β-unsaturated aldehydes (see scheme). The synthetic utility of this co-catalyzed reaction was demonstrated in the short total syntheses of (R)-(-)-curcumene and 4-aryl-2-ones. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Keywords
aldehydes; asymmetric catalysis; boronic acids; co-catalysts; total synthesis
National Category
Organic Chemistry
Identifiers
urn:nbn:se:miun:diva-18083 (URN)10.1002/ange.201208634 (DOI)000313688100012 ()2-s2.0-84872316330 (Scopus ID)
Note

Article first published online: 23 NOV 2012

Available from: 2012-12-20 Created: 2012-12-20 Last updated: 2017-12-06Bibliographically approved
Ma, G., Lin, S., Ibrahem, I., Kubik, G., Liu, L., Sun, J. & Cordova, A. (2012). Achiral Co-Catalyst Induced Switches in Catalytic Asymmetric Reactions on Racemic Mixtures (RRM): From Stereodivergent RRM to Stereoconvergent Deracemization by Combination of Hydrogen Bond Donating and Chiral Amine Catalysts. Advanced Synthesis and Catalysis, 354(14-15), 2865-2872
Open this publication in new window or tab >>Achiral Co-Catalyst Induced Switches in Catalytic Asymmetric Reactions on Racemic Mixtures (RRM): From Stereodivergent RRM to Stereoconvergent Deracemization by Combination of Hydrogen Bond Donating and Chiral Amine Catalysts
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2012 (English)In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 354, no 14-15, p. 2865-2872Article in journal (Refereed) Published
Abstract [en]

A stereochemical divergent approach for the highly enantioselective synthesis of distinct bicyclic products with multiple stereocenters from a racemate using a single chiral catalyst is disclosed. It is based on switches of the overall reaction pathways in the chiral amine-catalyzed cascade reactions between racemic ?-nitro ketones and a,beta-unsaturated aldehydes using different achiral co-catalysts. The utility of the method is exemplified by the highly diasteroselective switch and stereoconvergent deracemization process by combination of chiral amine and achiral hydrogen-bond-donating catalysts.

Keywords
cascade reactions; deracemization; dynamic asymmetric catalysis; hydrogen-bond donor; organocatalysis; reactions on racemic mixtures; stereodivergence
National Category
Organic Chemistry
Identifiers
urn:nbn:se:miun:diva-17532 (URN)10.1002/adsc.201200357 (DOI)000309907300037 ()2-s2.0-84869031085 (Scopus ID)
Available from: 2012-11-30 Created: 2012-11-30 Last updated: 2017-12-07Bibliographically approved
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