jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Beatriz Saavedra | Xavier Marset | Gabriela Guillena | Diego J. Ramón
Source: European Journal of Organic Chemistry (article, 2020-04-14)
Field: Chemistry — Organic Chemistry

Multicomponent Synthesis of Sulfones and Sulfides from Triarylbismuthines and Sodium Metabisulfite in Deep Eutectic Solvents This study describes a novel and catalyst‐free methodology for the multicomponent synthesis of a broad range of sulfones, disulfides, and sulfides from non‐toxic triarylbismuthines (Ar 3 Bi) and sodium metabisulfite (Na 2 S 2 O 5 ) in deep eutectic solvents (DESs). The fine tuning of the DESs properties allowed the solubility of all reagents, enhancing their reactivity, as well as, the recyclability of the reaction medium for at least 5 consecutive cycles. Thus, this versatile strategy uses non‐toxic reagents without the need of metal catalysts in a sustainable solvent, being an interesting alternative to traditional hazardous protocols. Sodium metabisulfite ; Chemistry ; Reagent ; Eutectic system ; Catalysis ; Deep eutectic solvent ; Solubility ; Reactivity (psychology) ; Solvent ; Organic chemistry ; Green chemistry ; Combinatorial chemistry ; Reaction mechanism Sulfur-Based Synthesis Techniques ; Chemical Synthesis and Reactions ; Phenothiazines and Benzothiazines Synthesis and Activities
Authors: Rafał Zuzak | Pedro Brandimarte | Piotr Olszowski | Irena Izydorczyk | Marios S. Markoulides | Bartosz Such | Marek Kolmer | Marek Szymoński | Aran García-Lekue | Daniel Sánchez‐Portal | André Gourdon | Szymon Godlewski
Source: The Journal of Physical Chemistry Letters (article, 2020-11-23)
Field: Materials Science — Materials Chemistry

On-Surface Synthesis of Chlorinated Narrow Graphene Nanoribbon Organometallic Hybrids Graphene nanoribbons (GNRs) and their derivatives attract growing attention due to their excellent electronic and magnetic properties as well as the fine-tuning of such properties that can be obtained by heteroatom substitution and/or edge morphology modification. Here, we introduce graphene nanoribbon derivatives-organometallic hybrids with gold atoms incorporated between the carbon skeleton and side Cl atoms. We show that narrow chlorinated 5-AGNROHs (armchair graphene nanoribbon organometallic hybrids) can be fabricated by on-surface polymerization with omission of the cyclodehydrogenation reaction by a proper choice of tailored molecular precursors. Finally, we describe a route to exchange chlorine atoms connected through gold atoms to the carbon skeleton by hydrogen atom treatment. This is achieved directly on the surface, resulting in perfect unsubstituted hydrogen-terminated GNRs. This will be beneficial in the molecule on-surface processing when the preparation of final unsubstituted hydrocarbon structure is desired. Graphene ; Heteroatom ; Group 2 organometallic chemistry ; Carbon fibers ; Graphene nanoribbons ; Materials science ; Molecule ; Hydrogen ; Atom (system on chip) ; Surface modification ; Nanotechnology ; Chemistry ; Organic chemistry ; Composite number ; Physical chemistry ; Composite material Graphene research and applications ; Surface Chemistry and Catalysis ; Nanomaterials for catalytic reactions
Authors: Emmanouil Vereroudakis | Dimitris Vlassopoulos
Source: Progress in Polymer Science (article, 2020-11-17)
Field: Materials Science — Polymers and Plastics

Tunable dynamic properties of hydrogen-bonded supramolecular assemblies in solution Supramolecular chemistry ; Nanotechnology ; Rheology ; Supramolecular polymers ; Materials science ; Viscoelasticity ; Microelectronics ; Field (mathematics) ; Hydrogen bond ; Polymer science ; Chemical physics ; Computer science ; Chemistry ; Molecule ; Organic chemistry Polymer composites and self-healing ; Surfactants and Colloidal Systems ; Lipid Membrane Structure and Behavior
Authors: Bernadett Adamcsik | Enikő Nagy | Béla Urbán | Péter Szabó | Péter Pekker | Rita Skoda‐Földes
Source: RSC Advances (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

Palladium nanoparticles on a pyridinium supported ionic liquid phase: a recyclable and low-leaching palladium catalyst for aminocarbonylation reactions A new SILP (Supported Ionic Liquid Phase) palladium catalyst was prepared and characterized by <sup>13</sup>C and <sup>29</sup>Si CP MAS NMR, DTG, FTIR and TEM. The presence of the grafted pyridinium cations on the surface of the support was found to result in the formation of highly dispersed Pd nanoparticles with their diameter in the range of 1-2 nm. The catalyst was proved to be active not only in the aminocarbonylation of some model compounds but also in the synthesis of active pharmaceutical ingredients. Catalyst recycling and palladium leaching studies were carried out for the first time in aminocarbonylations leading to CX-546(1-(1,4-benzodioxan-6-ylcarbonyl)piperidine), Moclobemide, Nikethamide and a precursor of Finasteride. The latter reaction proves that not only aryl iodides but also an iodoalkene can be converted into the products with the help of the heterogeneous catalyst. The results show that the conditions should be always fine-tuned in the reactions of different substrates to achieve optimal results. Palladium loss was also observed to depend considerably on the nature of the reaction partners. Palladium ; Ionic liquid ; Catalysis ; Leaching (pedology) ; Pyridinium ; Chemistry ; Ionic bonding ; Phase (matter) ; Organic chemistry ; Ion ; Environmental science Catalytic Cross-Coupling Reactions ; Ionic liquids properties and applications ; Chemical Synthesis and Reactions
Authors: Dipankar Das | Eunchong Cha | Sangji Lee | Hyun‐Soo Shin | Insup Noh
Source: Biomacromolecules (article, 2020-01-02)
Field: Materials Science — Polymers and Plastics

Effects of Molar Ratios of Two Immiscible Monomers toward Development of an Amphiphilic, Highly Stretchable, Bioadhesive, Self-Healing Copolymeric Hydrogel and its Mineral-Active Cellular Behavior Here, we report the striking properties such as high stretchability, self-healing, and adhesiveness of an amphiphilic copolymeric hydrogel (poly(acrylic acid)-poly(methyl methacrylate) (PAA-PMMA) gel) synthesized from two immiscible monomers-acrylic acid (AA) and methyl methacrylate (MMA)-through a simple free radical polymerization in an aqueous medium. The developed hydrogel, with a specific molar ratio of MMA and AA, is self-healable, which is attributed to the hydrophobic interaction arising from methyl groups of PMMA, as well as the breakdown and reformation of sacrificial noncovalent cross-linking through the weak hydrogen bonds between the carboxylic acid groups of PAA and methoxy groups of PMMA. The energy dissipation values in the hysteresis test signify the excellent self-recoverability of the hydrogel. The developed hydrogel showed adhesive behavior to the surfaces of polystyrene, glass, wood, metal, stone, ceramics, pork skin, and human skin. The physical and mechanical properties of the PAA-PMMA gel were fine-tuned through changes in the MMA/AA ratio and pH. Moreover, the PAA-PMMA hydrogel can serve as a template for calcium phosphate mineralization to yield a hydrogel composite, which improved MC3T3 cell adhesion and proliferation. Overall, we propose that depending on synthesis parameters and other scenarios, the synthesized PAA-PMMA hydrogel could potentially be employed in varying biomedical and industrial applications. Bioadhesive ; Amphiphile ; Monomer ; Copolymer ; Polymer chemistry ; Chemistry ; Molar ; Self-healing ; Chemical engineering ; Polymer ; Materials science ; Organic chemistry ; Dentistry Polymer composites and self-healing ; Hydrogels: synthesis, properties, applications ; Advanced Polymer Synthesis and Characterization
Authors: Ming Kong | Xin Feng | Jing Li | Zhao‐Bo Hu | Jia Wang | Xiao‐Jiao Song | Zhao-Yang Jing | Yi‐Quan Zhang | You Song
Source: Dalton Transactions (article, 2020-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Structurally modulated single-ion magnets of mononuclear β-diketone dysprosium(<scp>iii</scp>) complexes Five β-diketone based Dy(iii) single-ion magnets (SIMs), [DyIII(TTA)3(AIP)]·0.5CH3CH2OH·0.5H2O (1), [DyIII(TTA)3(APIP)]·2CH3OH·H2O (2), [DyIII(TTA)3(DPP)] (3), [DyIII(TTA)3(BPP)]·0.5CH3CH2OH (4) and [DyIII(TTA)3(AIP)]·1.5H2O (5), were fully synthesized through alteration of their phenanthroline derivates (AIP = 2-(anthracen-9-yl)-1H-imidazo[4,5-f][1,10]phenanthroline, APIP = 2-(4-(anthracen-9-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, DPP = 2,3-diphenylpyrazino[2,3-f][1,10]phenanthroline and BPP = 2,3-bis(2,5-dimethylthiophen-3-yl)pyrazino[2,3-f][1,10]phenanthroline). Magnetic investigations reveal that all the complexes perform as SIMs, with notably different effective barriers of 69.4 K (1), 147.3 K (2), 122.1 K (3) and 234.2 K (4) in zero direct current (dc) field. Complexes of 2 and 4 possess almost twofold higher effective barriers compared to 1 and 3. By analyzing the crystal structures, the distinct magnetic dynamics was found to stem from the variation in intermolecular hydrogen bond interactions and charge delocalization of auxiliary ligands. With the help of ab initio calculations, a change of auxiliary ligand brings about varying intensities of quantum tunnelling magnetization (QTM), which account for the distinguishable magnetic dynamics. With a combination of experimental and theoretical analyses, this work provides a visual and instructive perspective to the understanding of fine tuning auxiliary ligands to design structurally modulated SIMs of mononuclear β-diketone dysprosium(iii) complexes. Dysprosium ; Ion ; Chemistry ; Crystallography ; Magnet ; Materials science ; Inorganic chemistry ; Physics ; Organic chemistry Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Electron Spin Resonance Studies
Authors: Deborah Romito | Nicolas Biot | Francesco Babudri | Davide Bonifazi
Source: New Journal of Chemistry (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

Non-covalent bridging of bithiophenes through chalcogen bonding grips In this work, chalcogen functionalized dithiophenes, equipped on both extremities with chalcogen-bonding recognition heterocycles, have been prepared following two synthetic pathways. Chemistry ; Chalcogen ; Bridging (networking) ; Covalent bond ; Nanotechnology ; Organic chemistry Photochromic and Fluorescence Chemistry ; Conducting polymers and applications ; Sulfur-Based Synthesis Techniques
Authors: Rostislav Skitchenko | Dmitrii Usoltsev | M. V. Uspenskaya | Andrey V. Kajava | Albert Guskov
Source: Bioinformatics (article, 2020-01-29)
Field: Materials Science — Materials Chemistry

Census of halide-binding sites in protein structures Supplementary data are available at Bioinformatics online. Halide ; Moiety ; Chemistry ; Halogen ; Binding site ; Function (biology) ; Pipeline (software) ; Crystallography ; Stereochemistry ; Computer science ; Biochemistry ; Inorganic chemistry ; Biology ; Organic chemistry ; Genetics ; Programming language Enzyme Structure and Function ; Advanced Proteomics Techniques and Applications ; Fluoride Effects and Removal
Authors: Henrik H. Sønsteby | Jon E. Bratvold | Veronica A.-L. K. Killi | Devika Choudhury | Jeffrey W. Elam | Helmer Fjellvåg | Ola Nilsen
Source: Journal of Vacuum Science & Technology A Vacuum Surfaces and Films (article, 2020-10-20)
Field: Materials Science — Materials Chemistry

<i>tert</i>-butoxides as precursors for atomic layer deposition of alkali metal containing thin films Alkali metal containing materials have become increasingly attractive in a world hunting for sustainable energy materials and green functional devices. Lithium- and sodium battery technology, lead-free piezo- and ferroelectric devices, and record-breaking alkali doped tandem perovskite solar cells are among the applications where alkali metal-containing thin films get increasing attention. Atomic layer deposition (ALD) is one of the enabling thin film deposition techniques that offer chemical and geometrical versatility to realize the implementation of such thin films on an applicable scale. The drawback has until recently been a lack of available precursor chemistry that offers self-limiting growth that is fundamental to ALD. The alkali metal tert-butoxides have been shown to exhibit the necessary properties to facilitate saturating growth for Li-, Na-, K-, and Rb-containing compounds. However, the behavior of the tert-butoxides in ALD-growth has been considered difficult to unravel, with processes exhibiting limited control and low reproducibility. Very little has been reported on trends in reaction mechanisms as the mass of the alkali metal increases. Herein, we summarize the existing literature on the use of alkali metal tert-butoxides as precursors in ALD. We consider differences in the structure and behavior of the tert-butoxides as the alkali metal cation becomes heavier. In addition, we present precursor synthesis routes and key information on precursor structure, stability, and mechanistic behavior. Finally, we provide the first ever report of Cs-containing films by ALD to complement previous work on its lighter counterparts. Atomic layer deposition ; Alkali metal ; Thin film ; Nanotechnology ; Materials science ; Chemical engineering ; Deposition (geology) ; Chemistry ; Inorganic chemistry ; Organic chemistry Ferroelectric and Piezoelectric Materials ; Perovskite Materials and Applications ; Semiconductor materials and devices
Authors: Maximilian Scherger | Evangelia Bolli | Ana Rita Pombo Antunes | Sana M. Arnouk | Judith Stickdorn | Alexandra Van Driessche | Hansjörg Schild | Stephan Grabbe | Bruno G. De Geest | Jo A. Van Ginderachter | Lutz Nuhn
Source: Cells (article, 2020-10-01)
Field: Materials Science — Biomaterials

Transient Multivalent Nanobody Targeting to CD206-Expressing Cells via PH-Degradable Nanogels To target nanomedicines to specific cells, especially of the immune system, nanobodies can be considered as an attractive tool, as they lack the Fc part as compared to traditional antibodies and, thus, prevent unfavorable Fc-receptor mediated mistargeting. For that purpose, we have site-specifically conjugated CD206/MMR-targeting nanobodies to three types of dye-labeled nanogel derivatives: non-degradable nanogels, acid-degradable nanogels (with ketal crosslinks), and single polymer chains (also obtained after nanogel degradation). All of them can be obtained from the same reactive ester precursor block copolymer. After incubation with naïve or MMR-expressing Chinese hamster ovary (CHO) cells, a nanobody mediated targeting and uptake could be confirmed for the nanobody-modified nanocarriers. Thereby, the intact nanogels that display nanobodies on their surface in a multivalent way showed a much stronger binding and uptake compared to the soluble polymers. Based on their acidic pH-responsive degradation potential, ketal crosslinked nanogels are capable of mediating a transient targeting that gets diminished upon unfolding into single polymer chains after endosomal acidification. Such control over particle integrity and targeting performance can be considered as highly attractive for safe and controllable immunodrug delivery purposes. Nanogel ; Chinese hamster ovary cell ; Nanocarriers ; Chemistry ; Biophysics ; Endosome ; Drug delivery ; Biochemistry ; Receptor ; Biology Nanoparticle-Based Drug Delivery ; RNA Interference and Gene Delivery ; Monoclonal and Polyclonal Antibodies Research
Authors: Muthu Kumaran Gnanamani | Richard Garcia | Gary Jacobs | Kinga Góra‐Marek | Donald C. Cronauer | A. Jeremy Kropf | Christopher L. Marshall
Source: Applied Catalysis A General (article, 2020-06-26)
Field: Materials Science — Materials Chemistry

Effect of pretreatment conditions on acidity and dehydration activity of CeO2-MeOx catalysts Chemistry ; Catalysis ; Inorganic chemistry ; Cerium ; Fourier transform infrared spectroscopy ; Cerium oxide ; Pyridine ; Metal ; Lewis acids and bases ; Alcohol ; Adsorption ; X-ray absorption spectroscopy ; Nuclear chemistry ; Oxidation state ; Absorption spectroscopy ; Organic chemistry ; Chemical engineering Catalytic Processes in Materials Science ; Catalysis and Hydrodesulfurization Studies ; Catalysis and Oxidation Reactions
Authors: Hatem Abushammala
Source: Polymers (article, 2020-01-04)
Field: Materials Science — Biomaterials

Nano-Brushes of Alcohols Grafted onto Cellulose Nanocrystals for Reinforcing Poly(Butylene Succinate): Impact of Alcohol Chain Length on Interfacial Adhesion Despite the many interesting properties of cellulose nanocrystals (CNCs), their hydrophilicity is one of the main challenges for their processing with hydrophobic polymers and matrices. To overcome this challenge, this paper describes the preparation of brush-like CNCs with tailored surface properties by grafting alcohols of different chain lengths onto their surfaces. Ethanol, 1-butanol, 1-hexanol, and 1-octanol were grafted on the CNC surface using 2,4-toluene diisocyanate (TDI) as a linker. The CNCs were characterized for their structural, morphological, surface, and thermal properties. Because of the grafting, the water contact angle of the CNCs significantly increased from 32° to up to 120°, which was dependent on the chain length of the grafted alcohol. The thermal stability of the CNCs was also improved, mainly as a result of the reaction of TDI with the CNC hydroxyl groups. Later, the CNCs were used to reinforce films of poly(butylene succinate) (PBS), which were then characterized using dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA). An increase of up to two-fold in the storage modulus was observed using DMA, which was dependent on the chain length of the grafted alcohol. However, no change in the glass transition temperature or degradation temperature of PBS was detected. This approach is proved efficient for tailoring the surface properties of CNCs towards excellent interfacial adhesion in their composites. Materials science ; Thermogravimetric analysis ; Dynamic mechanical analysis ; Contact angle ; Chemical engineering ; Grafting ; Thermal stability ; Polymer chemistry ; Polymer ; Composite material Advanced Cellulose Research Studies ; Nanocomposite Films for Food Packaging ; Polysaccharides and Plant Cell Walls
Authors: Pablo Ríos | Amor Rodríguez | Salvador Conejero
Source: Chemical Communications (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

Enhancing the catalytic properties of well-defined electrophilic platinum complexes Platinum complexes have been often considered as the least reactive of the group 10 triad metals. Slow kinetics are behind this lack of reactivity but, still, some industrially relevant catalytic process are dominated by platinum compounds and sometimes different selectivities can be found in comparison to Ni or Pd. Nevertheless, during the last years, it has been reported that the catalytic behaviour of well-defined platinum derivatives can be improved through a judicious choice of their electronic and steric properties, leading to highly electrophilic or low-electron count platinum systems. In this feature article, we highlight some catalytic processes in which well-defined electrophilic platinum complexes or coordinatively unsaturated systems play an important role in their catalytic activity. Platinum ; Electrophile ; Catalysis ; Steric effects ; Reactivity (psychology) ; Chemistry ; Platinum group ; Combinatorial chemistry ; Organic chemistry Organometallic Complex Synthesis and Catalysis ; Catalytic Alkyne Reactions ; Asymmetric Hydrogenation and Catalysis
Authors: Linda K. Månsson | Feifei Peng | Jérôme J. Crassous | Peter Schurtenberger
Source: Soft Matter (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

A microgel-Pickering emulsion route to colloidal molecules with temperature-tunable interaction sites A simple Pickering emulsion route has been developed for the assembly of temperature-responsive poly(N-isopropylacrylamide) (PNIPAM) microgel particles into colloidal molecules comprising a small number of discrete microgel interaction sites on a central oil emulsion droplet. Here, the surface activity of the microgels serves to drive their assembly through adsorption to growing polydimethylsiloxane (PDMS) emulsion oil droplets of high monodispersity, prepared in situ via ammonia-catalysed hydrolysis and condensation of dimethyldiethoxysilane (DMDES). A dialysis step is employed in order to limit further growth once the target assembly size has been reached, thus yielding narrowly size-distributed, colloidal molecule-like microgel-Pickering emulsion oil droplets with well-defined microgel interaction sites. The temperature-responsiveness of the PNIPAM interaction sites will allow for the directional interactions to be tuned in a facile manner with temperature, all the way from soft repulsive to short-range attractive as the their volume phase transition temperature (VPTT) is crossed. Finally, the microgel-Pickering emulsion approach is extended to a mixture of PNIPAM and poly(N-isopropylmethacrylamide) (PNIPMAM) microgels that differ with respect to their VPTT, this in order to prepare patchy colloidal molecules where the directional interactions will be more readily resolved. Pickering emulsion ; Emulsion ; Colloid ; Chemical engineering ; Materials science ; Molecule ; Condensation ; Polydimethylsiloxane ; Nanotechnology ; Polymer chemistry ; Chemistry ; Organic chemistry Pickering emulsions and particle stabilization ; Proteins in Food Systems ; Micro and Nano Robotics
Authors: Markus Hecht | Pawaret Leowanawat | Tabea Gerlach | Vladimir Stepanenko | Matthias Stolte | Matthias Lehmann | Frank Würthner
Source: Angewandte Chemie (article, 2020-06-10)
Field: Materials Science — Biomaterials

Self‐Sorting Supramolecular Polymerization: Helical and Lamellar Aggregates of Tetra‐Bay‐Acyloxy Perylene Bisimide Abstract A new perylene bisimide (PBI), with a fluorescence quantum yield up to unity, self‐assembles into two polymorphic supramolecular polymers. This PBI bears four solubilizing acyloxy substituents at the bay positions and is unsubstituted at the imide position, thereby allowing hydrogen‐bond‐directed self‐assembly in nonpolar solvents. The formation of the polymorphs is controlled by the cooling rate of hot monomer solutions. They show distinctive absorption profiles and morphologies and can be isolated in different polymorphic liquid‐crystalline states. The interchromophoric arrangement causing the spectral features was elucidated, revealing the formation of columnar and lamellar phases, which are formed by either homo‐ or heterochiral self‐assembly, respectively, of the atropoenantiomeric PBIs. Kinetic studies reveal a narcissistic self‐sorting process upon fast cooling, and that the transformation into the heterochiral (racemic) sheetlike self‐assemblies proceeds by dissociation via the monomeric state. Chemistry ; Perylene ; Supramolecular chemistry ; Monomer ; Supramolecular polymers ; Lamellar structure ; Polymerization ; Self-assembly ; Quantum yield ; Hydrogen bond ; Photochemistry ; Imide ; Dissociation (chemistry) ; Crystallography ; Pyrene ; Fluorescence ; Polymer chemistry ; Polymer ; Molecule ; Crystal structure ; Organic chemistry Supramolecular Self-Assembly in Materials ; Luminescence and Fluorescent Materials ; Porphyrin and Phthalocyanine Chemistry