Article
Chemistry, Physical
Pablo D. Nieres, Victoria A. Vaillard, Juan Zelin, Nicolas I. Neuman, Andres F. Trasarti, Carlos R. Apesteguia, Santiago E. Vaillard
Summary: HG(2) is a reliable and extremely useful catalyst for synthesizing olefins, especially for the self-metathesis reaction of unsaturated fatty acid methyl esters. Silica gel is a promising support for large scale application of HG(2) due to its beneficial characteristics. However, storing the supported catalyst under atmospheric conditions at 298K significantly decreases its activity, which compromises its stability and applicability. Detailed experimental and spectroscopic studies, along with electronic structure calculations, shed light on the catalyst decomposition process.
Article
Polymer Science
Henry L. Cater, Iana Balynska, Marshall J. Allen, Benny D. Freeman, Zachariah A. Page
Summary: This paper presents a systematic study on ROMP with endo-norbornene monomers using stable chelated Ru-alkylidene initiators. The study shows that ROMP with endo-norbornene monomers is versatile and robust, providing access to polymers with excellent molecular weight control, low dispersities, good functional group tolerance, and high chain-end fidelity. The process is oxygen-tolerant and can be performed under ambient conditions, allowing for the synthesis of mechanically robust thermoplastics with high glass transition and decomposition temperatures.
Article
Chemistry, Multidisciplinary
Halenur Ozer, Dilan Arslan, Bengi Ozgun Ozturk
Summary: In this study, in situ formed ruthenium hydride species from Grubbs type catalysts were used as efficient catalysts for dehydrogenative alcohol coupling and sequential cross-metathesis/dehydrogenative coupling reactions. The selectivity of the catalysts can be tuned by using different bases to obtain different products. With the presence of a new ligand, the performance of the catalyst was significantly improved, yielding products in quantitative yields.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Energy & Fuels
Momo Yamane, Yuto Seo, Wahyu S. Putro, Miftah Faried, Vladimir Ya. Lee, Tomoteru Mizusaki, Yukio Takagi, Kazuhiro Matsumoto, Jun-Chul Choi, Norihisa Fukaya
Summary: A new ruthenium carbene complex 1 was synthesized and characterized, in which the 1Pr ligand was modified via the introduction of Me3Si-group at the 4-position of the NHC backbone. This second-generation Grubbs pre-catalyst 1 exhibited excellent catalytic activity in the ring-closing metathesis of diethyldiallylmalonate, showing significantly higher activity compared to the commercially available first-generation Grubbs pre-catalyst [C12(Cy3P)2Ru=CHPh] and comparable activity to the second-generation Grubbs pre-catalyst [C12(Cy3P)(1Pr)Ru=CHPh].
JOURNAL OF THE JAPAN PETROLEUM INSTITUTE
(2023)
Article
Multidisciplinary Sciences
Thomas G. Pattison, Shuo Wang, Robert D. Miller, Gang-yu Liu, Greg G. Qiao
Summary: Macroscale additive manufacturing has developed significantly, but nanoscale formation of polymeric features from the bottom-up is not yet achieved. This study demonstrates a rapid crosslinking technique using an atomic force microscope, enabling fast curing of crosslinkable polymers in the presence of catalysts.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Mona O. Albalawi, Laura Falivene, Abdesslem Jedidi, Osman Osman, Shaaban A. Elroby, Luigi Cavallo
Summary: Ruthenium based catalysts are successful in catalyzing metathesis processes for synthesizing new carbon-carbon bonds. The use of density functional theory (DFT) calculations has significantly contributed to the development of new catalysts by providing fundamental understandings. An in-depth computational study on the binding of anion ligands to the metal has provided key insights on the global properties and reactivity of the catalyst.
MOLECULAR CATALYSIS
(2021)
Article
Chemistry, Inorganic & Nuclear
Marthinus R. Swart, Linette Twigge, Elizabeth Erasmus, Charlene Marais, Barend C. B. Bezuidenhoudt
Summary: The use of p-cresol as an additive in the Grubbs second generation catalyst facilitates the cross-metathesis of acrylates with prop-1-en-1-ylbenzenes. The interaction between p-cresol and GII leads to the formation of a ruthenium benzylidene with hydrogen bonds, altering the electron densities on the metal center and the carbene.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Materials Science, Multidisciplinary
Anderson M. S. Medeiros, Cedric Le Coz, Henri Cramail, Etienne Grau
Summary: This study focused on synthesizing polycaryophyllene with controlled molar mass, using styrene as a chain transfer agent. The resulting Pcar showed varying molar masses and glass transition temperatures, with Pcar@Sty#02 emerging as a promising biobased plasticizer candidate for EPDM, improving flexibility compared to petroleum-based alternatives.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Xiuxiu Wang, Weizhen Zhao, Kotohiro Nomura
Summary: By using RuCl2(IMesH2)(CH-2-OiPr-C6H4) catalyst, ADMET polymerization of bis(undec-10-enoate) and isosorbide in ionic liquids at 50°C resulted in higher molecular weight polymers compared to previous reports. However, degradation of the polymer was observed upon scaling up the reaction. Tandem hydrogenation of the unsaturated polymer in a [Bmim]PF6-toluene biphasic system produced the corresponding saturated polymer.
Article
Chemistry, Multidisciplinary
Steven T. Diver, Elise Glickert, Laurence N. Rohde, Therese Wild
Summary: In this study, a variety of 1-aryl-1,3-dienes were converted from E to Z isomers through photocatalysis using Ru(bpy)(3)[PF6](2) and blue LED light. The enrichment of Z-isomers was achieved by selective triplet energy transfer from the photocatalyst. By combining catalytic ene-yne metathesis (EYM) and photocatalysis, a stereoconvergent synthesis of Z-1,3-dienes was achieved.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Mathis J. Benedikter, Janis V. Musso, Wolfgang Frey, Roman Schowner, Michael R. Buchmeiser
Summary: Despite their excellent selectivities and activities, Mo- and W-based catalysts for olefin metathesis have not been widely used due to their air sensitivity. The synthesized cationic-at-metal molybdenum and tungsten imido alkylidene NHC nitrile complexes are stable in air and can catalyze olefin metathesis reactions without prior activation. The presence of a nitrile ligand is crucial for their stability, while variations in imido and anionic ligands affect reactivities and stability.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Materials Science, Paper & Wood
Arnet Maria Antony, Masira Imtiyaz Chamanmalik, Vishal Kandathil, Harini G. Sampatkumar, B. S. Sasidhar, C. V. Yelamaggad, Siddappa A. Patil
Summary: A new N-heterocyclic carbene-palladium(II) complex grafted on cellulose was synthesized as a heterogeneous catalyst. The structure, morphology, thermal stability and chemical composition of the catalyst were confirmed by various analytical techniques. The catalyst exhibited excellent catalytic ability in Suzuki-Miyaura and Mizoroki-Heck cross-coupling reactions, with good tolerance to various functional groups and easy recovery by filtration.
Article
Chemistry, Physical
Samantha K. Cormier, Deryn E. Fogg
Summary: Ruthenium-promoted ring-opening metathesis polymerization (ROMP) can produce amine-functionalized polymers with antimicrobial, adhesive, and self-healing properties. However, the degradation of intermediates formed in metathesis of terminal olefins is a challenge. This study explores the relevance of these decomposition pathways to ROMP using the third-generation Grubbs catalyst.
Article
Chemistry, Physical
Samantha K. Cormier, Deryn E. Fogg
Summary: Ruthenium-promoted ring-opening metathesis polymerization (ROMP) provides potential routes for amine-functionalized polymers, but the presence of amines leads to degradation of the intermediates formed in metathesis reactions. This study examines the relevance of these degradation pathways to ROMP using the third-generation Grubbs catalyst. Primary alkylamines rapidly inhibit polymerization through fast adduct formation and nucleophilic attack, while bulkier, Bronsted-basic amines are less aggressive. The addition of HCl limits degradation and enables successful ROMP of otherwise challenging monomers.
Article
Chemistry, Multidisciplinary
Louis Monsigny, Anna Kajetanowicz, Karol Grela
Summary: This review discusses a distinct class of ruthenium olefin metathesis catalysts with unsymmetrical N-heterocyclic carbene (uNHC) ligands, highlighting their advantages such as thermodynamic stability, chemical latency, selectivity, and compatibility with green solvents in specialized metathesis transformations. Despite being niche, uNHC complexes have the potential to be implemented in various industrial processes like valorization of Fischer-Tropsch olefin fractions, ethenolysis of renewable products, and modern pharmaceutical production.
Article
Engineering, Environmental
Wan Zhang, Xiaozhou Ji, Mohammed Al-Hashimi, Chaoxia Wang, Lei Fang
Summary: Thermoresponsive polymer composites synthesized using a direct blending approach exhibit color change and emission brightness upon heating, with high reversibility and high-contrast signal output.
CHEMICAL ENGINEERING JOURNAL
(2021)
Review
Chemistry, Organic
Santhosh Kumar Podiyanachari, Hassan S. Bazzi, Mohammed Al-Hashimi
Summary: Synthesis of cycloolefin-based polymers via metathesis-accompanied cyclopolymerization and tandem ring-opening/ring-closing metathesis (RO/RCM) polymerization leads to highly functional cycloolefin ring-based polymers.
CURRENT ORGANIC CHEMISTRY
(2021)
Article
Materials Science, Multidisciplinary
Michael U. Ocheje, Marc Comi, Rui Yang, Zhihui Chen, Yao Liu, Nastaran Yousefi, Mohammed Al-Hashimi, Simon Rondeau-Gagne
Summary: Fluorination is a common strategy for improving the electronic properties of pi-conjugated materials, but its effects on thermal transitions and mechanical properties are not fully understood. This study evaluated the glass transition temperatures and mechanical properties of a series of fluorinated and/or alkylated benzothiadiazole-based polymers, and measured their electronic properties under strain through organic field-effect transistor fabrication. The results showed that fluorination embrittles conjugated polymer thin films, while alkylation softens them. The crack onset strains and electronic properties of the synthesized polymers were inversely proportional, and the electronic properties under strain increased with decreasing elastic moduli.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Physical
Nicholas I. Cool, Diane G. Sellers, Mohammed Al-Hashimi, Sarbajit Banerjee
Summary: Heating, cooling, and lighting contribute significantly to the energy consumption of buildings. Development of a thermochromic material can passively modulate solar heat gain, increasing building energy efficiency. This study demonstrates the manufacturing of thermochromic fenestration elements with high transparency and near-infrared modulation through alloying and encapsulation of nanocrystals.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Katelynn Edgehouse, Nicholas Starvaggi, Neil Rosenfeld, David Bergbreiter, Emily Pentzer
Summary: This study investigates the impact of polymer shell composition on the uptake of small molecule dye, showing that small changes in capsule shell composition can lead to different performance in small molecule uptake, providing insights into tailoring shell composition for specific applications.
Article
Polymer Science
Marc Comi, Salvador Moncho, Salahuddin Attar, Maciej Barlog, Edward Brothers, Hassan S. Bazzi, Mohammed Al-Hashimi
Summary: The synthesis and characterization of asymmetric alkoxy-fluoro-benzothiadiazole (BT) acceptor core derivatized with a series of heterocycles is reported. The effect of the different chalcogen atoms in the flanked-heterocycles on the physicochemical properties of the homopolymers is studied.
MACROMOLECULAR RAPID COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Jose Manuel Marin-Beloqui, Sandra Gomez, Hristo Ivov Gonev, Marc Comi, Mohammed Al-Hashimi, Tracey M. Clarke
Summary: One of the main assumptions in the design of new conjugated polymer materials for organic electronics is that higher coplanarity leads to greater conjugation along the polymer backbone. However, this study presents a case that contradicts this assumption. Different diselenophene-based polymers were studied, and it was found that a more rigid, planar structure did not lead to increased conjugation.
Article
Materials Science, Multidisciplinary
Sergio Gamez-Valenzuela, Marc Comi, Sandra Rodriguez Gonzalez, M. Carmen Ruiz Delgado, Mohammed Al-Hashimi, Rocio Ponce Ortiz
Summary: In this study, a series of donor-acceptor copolymers were synthesized and characterized for their enhanced electrical performance in organic field effect transistors (OFETs) by gradually fluorinating the molecules to enhance intrachain interactions. The impact of fluorination on the material properties was analyzed using spectroscopic and electrochemical techniques, as well as density functional theory calculations. The results showed that fluorination, particularly in the isoindigo unit, progressively increased the polymer coplanarity and electron affinity, resulting in balanced ambipolar charge transport in the fluorinated polymers.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Review
Chemistry, Multidisciplinary
Upendar Reddy Gandra, Santhosh Kumar Podiyanachari, Hassan S. Bazzi, Mohammed Al-Hashimi
Summary: This mini-review presents recent advances in the synthesis of functional materials using ring-opening metathesis polymerization (ROMP)-derived poly(olefins) for drug release, sensing, and cellular uptake in the past seven years (2015-2022). The review highlights the highly promising potential of ROMP-derived well-defined functional poly(olefins) for medical and biological studies. It provides valuable insights for the design and development of new smart and flexible-functionality ROMP-based polymeric materials for various biological applications.
Article
Chemistry, Physical
Jolanda Simone Mueller, Marc Comi, Flurin Eisner, Mohammed Azzouzi, Diego Herrera Ruiz, Jun Yan, Salahuddin Sayedshabbir Attar, Mohammed Al-Hashimi, Jenny Nelson
Summary: The charge-generation processes limiting the performance of low-offset organic bulk-heterojunction solar cells were investigated by studying newly synthesized PBDB-T-derivative donor polymers. The ionisation energy (IE) of the donor polymers was tuned via functional group and backbone modifications. It was found that reducing the donor-acceptor IE offsets decreased nonradiative voltage losses but severely suppressed photocurrent generation. This reduced efficiency was attributed to a decrease in local exciton dissociation efficiency as well as charge transfer (CT) state dissociation efficiency.
ACS ENERGY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Salahuddin Attar, Rui Yang, Zhihui Chen, Xiaozhou Ji, Marc Comi, Sarbajit Banerjee, Lei Fang, Yao Liu, Mohammed Al-Hashimi
Summary: Ladder-type thiazole-fused S,N-heteroacenes with extended pi-conjugation have been synthesized and characterized. These compounds exhibit good optical, electronic, and thermal properties and show promising charge transport behavior in organic thin-film transistors.
Article
Materials Science, Multidisciplinary
Zihao Feng, Marc Comi, Yi Ren, Dusan Sredojevic, Salahuddin Attar, Jiaqin Yang, Zhanpeng Wang, Ruo-Si Chen, Su-Ting Han, Mohammed Al-Hashimi, Ye Zhou
Summary: In this study, three pi-conjugated polymers based on indacenodithieno[3,2-b]thiophene (IDTT) were compared, and the influence of the co-monomer on thermal, optical, and electrochemical properties was evaluated. The effect of alkoxy substituents on the planarity of the polymer backbone was investigated, and the enhanced thin-film crystallinity and morphological properties were confirmed. The constructed organic field-effect transistors (OFETs) and memory devices showed excellent performance. Furthermore, synaptic behaviors were successfully simulated, providing insights for future applications of organic electronics in information storage and neuromorphic computing.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
John Barron, Salahuddin Attar, Payal Bhattacharya, Ping Yu, Mohammed Al-Hashimi, Suchismita Guha
Summary: This study reports on the synthesis of thiazole flanked fluorinated isoindigo (IID) copolymers and demonstrates their field-effect transistor (FET) properties. By varying the FET geometries and dielectric layers, n-type transport and high electron carrier mobility are achieved. In addition, fluorination is shown to enhance the nonlinear optical properties.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Sai Che, Chenxuan Li, Chenxu Wang, Wasif Zaheer, Xiaozhou Ji, Bailey Phillips, Guvanch Gurbandurdyyev, Jessica Glynn, Zi-Hao Guo, Mohammed Al-Hashimi, Hong-Cai Zhou, Sarbajit Banerjee, Lei Fang
Summary: The synthesis of porous graphitic carbon (PGC) through acid-mediated aldol triple condensation and low-temperature graphitization enables ultramicroporosity and high electrical conductivity, with solution-processability facilitating further applications.
Article
Materials Science, Multidisciplinary
Marc Comi, Dhananjaya Patra, Rui Yang, Zhihui Chen, Alexandra Harbuzaru, Yiming Wubulikasimu, Sarbajit Banerjee, Rocio Ponce Ortiz, Yao Liu, Mohammed Al-Hashimi
Summary: The study reports the synthesis of five copolymers based on benzothiadiazole derivatives as strong acceptors for enhancing pi-stacking and improving charge carrier transport properties. The copolymers showed enhanced solubility, effective packing between chains, favorable optical and electrochemical properties, and maximum charge carrier mobility of 0.67 cm(2) V-1 s(-1) for some copolymers.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
