jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Croix J. Laconsay | Anna Pla‐Quintana | Dean J. Tantillo
Source: ChemRxiv (preprint, 2021-11-16)
Field: Chemistry — Organic Chemistry

Effects of Axial Solvent Coordination to Dirhodium Complexes on Reactivity and Selectivity in C–H Insertion Reactions: A Computational Study Density functional theory calculations were used to systematically explore the effects of axial ligation by solvent molecules on the reactivity and selectivity of dirhodium tetracarboxylates with diazo compounds in the context of C–H insertion into propane. Insertions on three types of diazo compounds—acceptor/acceptor, donor/acceptor, and donor/donor—promoted by dirhodium tetraformate were tested with and without axial solvent ligation for no surrounding solvent, dichloromethane, isopropanol, and acetonitrile. Magnitudes, origins, and consequences of structural and electronic changes arising from axial ligation were characterized. The results suggest that axial ligation affects barriers for N2 extrusion and C–H insertion, the former to a larger extent. Reactivity (psychology) ; Chemistry ; Dichloromethane ; Diazo ; Acetonitrile ; Acceptor ; Solvent ; Context (archaeology) ; Propane ; Selectivity ; Photochemistry ; Density functional theory ; Medicinal chemistry ; Computational chemistry ; Catalysis ; Organic chemistry Cyclopropane Reaction Mechanisms ; Catalytic C–H Functionalization Methods ; Synthesis and Catalytic Reactions
Authors: Jie Qi Ng
Source: Institutional Repositories DataBase (IRDB) (article, 2021-01-18)
Field: Chemistry — Organic Chemistry

Chemoselective Transesterification of Methyl (Meth)acrylates Catalyzed by Sodium(I) or Magnesium(II) Aryloxides A highly chemoselective transesterification of methyl (meth)acrylates catalyzed by sterically demanding 2,6-di-tert-butyl-4-methylphenol-derived NaOAr or Mg(OAr)2 was developed. The desired transesterification proceeded without the undesired Michael additions under mild reaction conditions at 25 °C, and various primary and secondary alcohols, diols, triol, and tetraol on a scale of up to 10 mmol could provide the corresponding functionalized acrylates in high yields. Transition states were proposed based on monomeric and dimeric active species, and computational density functional theory calculations strongly supported high chemoselectivity to minimize undesired Michael additions. Transesterification ; Catalysis ; Magnesium ; Meth- ; Chemistry ; Sodium ; Chemoselectivity ; Medicinal chemistry ; Organic chemistry ; Copolymer Chemical Synthesis and Reactions ; Asymmetric Hydrogenation and Catalysis ; Inorganic and Organometallic Chemistry
Authors: Carmen Leitner | Andrzej L. Sobolewski | Michał Cyran ́ski | Daniel T. Gryko | Zhimin Hu | Mingyu Huo | Ying Yuan | Yi Long | Sebastian B. Beil | Dennis Pollok | Siegfried R. Waldvogel | Q. Zhao | Shuang‐Nan Zhang | Fan Wu | Dongqi Li | Xintong Zhang | W Chen | Baolin Xing | Yasuaki Kondo | Hiromi Nonaka | Yoichi Takakusagi | Shinsuke Sando | Michael Schmitt | Maximilian Mayländer | Julian Goost | Sabine Richert | Ingo Krossing | C. Y. Wu | Xingyu Jiang | Z. Wang | Huanchen Sha | Zhe Lin | Z. Huang | X Long | M Humphrey | Chen‐Yu Zhang | Ross Thyer | Simon d’Oelsnitz | Meridith Blevins | David Klein | Jennifer S. Brodbelt | A Ellington | Y. G. Xie | Xiao-Li Yang | Jingyi Xu | Huifang Chai | Hui Liu | Jian Zhang | Jing Song | Y. Gao | Zhenmin Jin | Chi Yan | Niklas Grabicki | Kévin Nguyen | Stephan Weidner | Oliver Dumele∞ | J.D. Baars | Isabelle Grimm | Dirk Blunk | J.-M Neudçrfl | Holger Schmalz | S. S. Fang | Jinglan Tan | Jie Pan | H Zhang | Yiqun Chen | Xiaomin Ren | Timothy C. Wang | Y. -T Ang | Cliona M. McHale | Xiaoping Wang | Chi K. Chang | Yu-Neng Chuang | Watchareeya Kaveevivitchai | T. Chen | Peng Dong | Johannes Stellmacher | Lydia M. Bouchet | Marius Nieke | Ashutosh Kumar | E O Sorio-Blanco | Gunther W. Nagel | Silke B. Lohan | Christian Teutloff | Alexa Patzelt | Monika Schäfer‐Korting | María Paula Yávar Calderón | Martina C. Meinke | Ulrike Alexiev | Y Wang | Shuangyu Xu | Liwei Shi | Cathleen Teh | Qi Guo | B. Liu | A Chandra | Mohammed Ansari | I Monte-Pørez | Subhas C. Kundu | Gopalan Rajaraman
Source: Angewandte Chemie International Edition (article, 2021-06-18)
Field: Materials Science — Materials Chemistry

Graphical Abstract: Angew. Chem. Int. Ed. 27/2021 Coordination Complexes In their Communication on page 14800, Ingo Krossing et al. report the synthesis of the first homoleptic nickel carbonyl cation [Ni(CO) 4 ] . and the nickel tricarbonylnitrosyl cation [Ni(CO) 3 (NO)] in the condensed phase. Citation ; INT ; Computer science ; Library science ; Information retrieval ; Programming language Porphyrin and Phthalocyanine Chemistry ; Synthesis and Properties of Aromatic Compounds ; Molecular Sensors and Ion Detection
Authors: William James | Colette M. Sullivan | Nicholas Marshall
Source: ChemRxiv (preprint, 2021-02-26)
Field: Chemistry — Inorganic Chemistry

Etching and Polymerization Reactions of Alkoxythiophenes in HKUST-1: Choosing Between Filled and Core-Shell MOF/Polymer Composite Structures In an earlier report, we found that neat 3,4-ethylenedioxythiophene (EDOT) directly reacts with HKUST-1 to form a core-shell composite in which the HKUST-1 surface is coated with conjugated polymer, while unsubstituted thiophenes formed a filled composite where polythiophene is contained in the MOF's pores. In this work, we found that EDOT and 3-methoxythiophene (3MOT), which react in the neat form to form core-shell composites, can be loaded into HKUST-1 pores without reaction when dissolved in hexanes. To a lesser extent, 3-hexyloxythiophene (3HOT) can be loaded in the same way. These hexane-loaded composites can then be heated, resulting in the formation of a 'filled' composite. This finding allows us to choose to prepare either a core-shell or a filled composite by selecting reaction conditions. The process of heating with alkoxythiophenes results in a morphology change in the HKUST-1 material. Composites were characterized by nitrogen sorption measurements, powder X-ray diffraction, and vibrational spectroscopy. Composite number ; Polymerization ; Materials science ; Polythiophene ; Composite material ; Polymer ; Core (optical fiber) ; Shell (structure) ; Sorption ; Chemical engineering ; Etching (microfabrication) ; Polymer chemistry ; Conductive polymer ; Chemistry ; Organic chemistry ; Layer (electronics) ; Adsorption Metal-Organic Frameworks: Synthesis and Applications ; Polyoxometalates: Synthesis and Applications ; Covalent Organic Framework Applications
Authors: Miguel A. Rivero‐Crespo | Georgios Toupalas | Bill Morandi
Source: ChemRxiv (preprint, 2021-02-23)
Field: Materials Science — Materials Chemistry

Preparation of Versatile, Porous Poly-Arylthioethers by Reversible Pd-Catalysed C–S/C–S Metathesis Porous organic frameworks have shown a number of promising properties; however, their industrial application is usually hampered due to the lability of their linkages (imine, boroxine, etc.). Inspired by the outstanding chemical, mechanical and thermal resistance of the 1D polymer polyphenylene sulfide (PPS), we hypothesized that 2D and 3D poly-arylthioether frameworks would merge the attractive features common to porous frameworks and PPS in a single material. Herein, we report a Pd-catalysed C–S/C–S metathesis-based method to prepare new porous poly-arylthioether frameworks in good yields. The self-correcting nature of the process has enabled the synthesis of new, robust materials with high surface areas. Despite the frameworks’ extreme resistance to harsh chemicals, they can be fully recycled to recover the original building blocks using the same catalytic reaction. In addition, we demonstrate preliminary results showing that these materials have great potential in several environmentally relevant applications including metal capture, metal sensing and heterogeneous catalysis. In a broader context, these results clearly demonstrate the untapped potential of emerging single-bond metathesis reactions in the preparation of new materials. Metathesis ; Catalysis ; Imine ; Materials science ; Context (archaeology) ; Porosity ; Polymer ; Porous medium ; Metal-organic framework ; Nanotechnology ; Chemical engineering ; Organic chemistry ; Chemistry ; Polymerization ; Composite material ; Adsorption Covalent Organic Framework Applications ; Advanced Photocatalysis Techniques ; MXene and MAX Phase Materials
Authors: William James | Colette M. Sullivan | Nicholas Marshall
Source: ChemRxiv (preprint, 2021-02-16)
Field: Chemistry — Inorganic Chemistry

Etching and Polymerization Reactions of Alkoxythiophenes in HKUST-1: Choosing Between Filled and Core-Shell Composite Structures In an earlier report, we found that neat 3,4-ethylenedioxythiophene (EDOT) directly reacts with HKUST-1 to form a core-shell composite in which the HKUST-1 surface is coated with conjugated polymer, while unsubstituted thiophenes formed a filled composite where polythiophene is contained in the MOF's pores. In this work, we found that EDOT and 3-methoxythiophene (3MOT), which react in the neat form to form core-shell composites, can be loaded into HKUST-1 pores without reaction when dissolved in hexanes. To a lesser extent, 3-hexyloxythiophene (3HOT) can be loaded in the same way. These hexane-loaded composites can then be heated, resulting in the formation of a 'filled' composite. This finding allows us to choose to prepare either a core-shell or a filled composite by selecting reaction conditions. The process of heating with alkoxythiophenes results in a morphology change in the HKUST-1 material. Composites were characterized by nitrogen sorption measurements, powder X-ray diffraction, and vibrational spectroscopy. Composite number ; Polythiophene ; Polymerization ; Materials science ; Composite material ; Core (optical fiber) ; Shell (structure) ; Sorption ; Etching (microfabrication) ; Chemical engineering ; Polymer ; Hexane ; Conductive polymer ; Chemistry ; Organic chemistry ; Layer (electronics) ; Adsorption Metal-Organic Frameworks: Synthesis and Applications ; Polyoxometalates: Synthesis and Applications ; Covalent Organic Framework Applications
Authors: M Stenzel | S. J. Zhao | Ke Yan | Jiajun Zhang | Benyuan Sun | Gang Wang | Linheng Li | Shuchang Xu | Yan Hu | Xiaomian Li | H Yazd | Tao Huang | Can Cui | Jun Jiang | Weihong Tan | Su May Liew | Xiang Qin | Jian Zhou | Wei Huang | S. Bing Yao | Miriam Schulte | Steffen Bochenek | Monia Brugnoni | Andrea Scotti | Ahmed Mourran | Walter Richtering | Udit Chawla | S. Ajith Perera | Andrew M. Fried | Bernhard Eitel | Norma T. Mertz | Manuj C. Weerasinghe | A Pitman | M Struts | Léonie Cussol | Laura Mauran‐Ambrosino | Jérémie Buratto | A Yb Elorusova | Mathilde Neuville | Judith Osz | Sylvain Fribourg | Juliette Frémaux | Christel Dolain | Sally Goudreau | Natacha Rochel | Gilles Guichard | Mamatha Shetty | H Ang | Fei Chen | Nicholas R. Jaegers | Yi Liu | Donald M. Camaioni | O Gutiørrez | Johannes A. Lercher | Philipp Zimmermann | Deniz Ar | M Rçßler | Patrick Holze | Beatrice Cula | Christoph Herwig | Christian Limberg | Xiaoxiao Guo | Qing‐Hua Fan | Jizhou Wu | Peng Zhang | Weiwei Su | Lin Ji | Lei Hou | Yu Qin | Harald Ade | Longfei Ye | M Zhang | Yutao Li | M Reczyn | Dawid Pinkowicz | Kazuhiko Nakabayashi | Christian Näther | Jeremy L. Stanek | M. Kozieł | J Kalinowska-Tłus | Barbara Sieklucka | Shin‐ichi Ohkoshi | B Nowicka | Chunjie Liu | Daniel Chen | Xinyan Liu | Zhengyang Zhou | Jia Li | F. Z. Qi | C Wallach | Felix S. Geitner | A. Karttunen | T Fässler | Aliaa I. Shallan | Yakini Tavares | Mohammad M. Kashani | Michael C. Breadmore | Caitlin Priest | Yu Han | S Dong
Source: Angewandte Chemie International Edition (article, 2021-01-25)
Field: Chemistry — Organic Chemistry

Graphical Abstract: Angew. Chem. Int. Ed. 5/2021 Soft Matter Nanogels adsorbed to the solid/water interface are studied by AFM in the Research Article by Walter Richtering et al. on page 2280. Force Volume measurements reveal the extraordinary disk-like and homogeneous structure of the nanogels. Citation ; INT ; Computer science ; Library science ; Information retrieval ; Chemistry ; Programming language Click Chemistry and Applications ; Carbon dioxide utilization in catalysis ; Radical Photochemical Reactions
Authors: Hyunseok Kim | Jiayu Zhao | Jinhye Bae | Liana M. Klivansky | Eric A. Dailing | Yi Liu | John R. Cappiello | K. Barry Sharpless | Peng Wu
Source: ChemRxiv (preprint, 2021-08-12)
Field: Materials Science — Polymers and Plastics

Chain-Growth SuFEx Polycondensation: Molecular Weight Control and Synthesis of Degradable Polysulfates Sulfur (Ⅵ) fluoride exchange (SuFEx) click chemistry has offered a facile and reliable approach to produce polysulfates and polysulfonates. However, the current SuFEx polymerization methods lack precise control of target molecular weight and dispersity. Herein, we report the first chain-growth SuFEx polycondensation process by exploiting unique reactivity and selectivity of S-F bonds under SuFEx catalysis. Given the higher reactivity of iminosulfur oxydifluoride versus fluorosulfate, the chain-growth SuFEx polycondensation is realized by using an iminosulfur oxydifluoride-containing compound as the reactive chain initiator and deactivated AB-type aryl silyl ether-fluorosulfates bearing an electron-withdrawing group as monomers. When DBU was utilized as the polymerization catalyst, precise control over polymer molecular weight and polydispersity are achieved. The resulting polymers possess great thermal stability but are easily degradable under mild acidic and basic conditions. Dispersity ; Condensation polymer ; Polymer chemistry ; Reactivity (psychology) ; Polymerization ; Silyl ether ; Monomer ; Chemistry ; Polymer ; Aryl ; Catalysis ; Ether ; Thermal stability ; Silylation ; Organic chemistry Synthesis and properties of polymers ; biodegradable polymer synthesis and properties ; Silicone and Siloxane Chemistry
Authors: Hyunseok Kim | Jiayu Zhao | Jinhye Bae | Liana M. Klivansky | Eric A. Dailing | Yi Liu | John R. Cappiello | K. Barry Sharpless | Peng Wu
Source: ChemRxiv (preprint, 2021-08-12)
Field: Materials Science — Polymers and Plastics

Chain-Growth SuFEx Polycondensation: Molecular Weight Control and Synthesis of Degradable Polysulfates Sulfur (Ⅵ) fluoride exchange (SuFEx) click chemistry has offered a facile and reliable approach to produce polysul-fates and polysulfonates. However, the current SuFEx polymerization methods lack precise control of target molecular weight and dispersity. Herein, we report the first chain-growth SuFEx polycondensation process by exploiting unique reactivity and selectivity of S-F bonds under SuFEx catalysis. Given the higher reactivity of iminosulfur oxydifluoride versus fluorosulfate, the chain-growth SuFEx polycondensation is realized by using an iminosulfur oxydifluoride-containing compound as the reactive chain initiator and deactivated AB-type aryl silyl ether-fluorosulfates bearing an electron-withdrawing group as monomers. When DBU was utilized as the polymerization catalyst, precise control over polymer molecular weight and polydispersity are achieved. The resulting polymers possess great thermal stability but are easily degradable under mild acidic and basic conditions. Dispersity ; Condensation polymer ; Polymer chemistry ; Reactivity (psychology) ; Silyl ether ; Polymerization ; Monomer ; Chemistry ; Polymer ; Catalysis ; Aryl ; Ether ; Thermal stability ; Organic chemistry ; Silylation Synthesis and properties of polymers ; Silicone and Siloxane Chemistry ; biodegradable polymer synthesis and properties
Authors: Yangyang Shen | Franziska Schoenebeck | Ignacio Funes‐Ardoiz | Tomislav Rovis
Source: ChemRxiv (preprint, 2021-04-19)
Field: Chemistry — Organic Chemistry

Site-Selective A-C-H Functionalization of Trialkylamines via Reversible Hydrogen Atom Transfer Catalysis Trialkylamines are widely found in naturally-occurring alkaloids, synthetic agrochemicals, biological probes, and especially pharmaceuticals agents and pre-clinical candidates. Despite the recent breakthrough of catalytic alkylation of dialkylamines, the selective a-C(sp3 )–H bond functionalization of widely available trialkylamine scaffolds holds promise to streamline complex trialkylamine synthesis, accelerate drug discovery and execute late-stage pharmaceutical modification with complementary reactivity. However, the canonical methods always result in functionalization at the less-crowded site. Herein, we describe a solution to switch the reaction site through fundamentally overcoming the steric control that dominates such processes. By rapidly establishing an equilibrium between a-amino C(sp3 )-H bonds and a highly electrophilic thiol radical via reversible hydrogen atom transfer, we leverage a slower radical-trapping step with electron-deficient olefins to selectively forge a C(sp3 )-C(sp3 ) bond with the more-crowded a-amino radical, with the overall selectivity guided by Curtin-Hammett principle. This subtle reaction profile has unlocked a new strategic concept in direct C-H functionalization arena for forging C– C bonds from a diverse set of trialkylamines with high levels of site-selectivity and preparative utility. Simple correlation of site-selectivity and 13C NMR shift serves as a qualitative predictive guide. The broad consequences of this dynamic system, together with the ability to forge N-substituted quaternary carbon centers and implement late-stage functionalization techniques, holds tremendous potential to streamline complex trialkylamine synthesis and accelerate drug discovery Chemistry ; Surface modification ; Selectivity ; Combinatorial chemistry ; Catalysis ; Alkylation ; Electrophile ; Steric effects ; Hydrogen atom ; Organic chemistry ; Alkyl Catalytic C–H Functionalization Methods ; Radical Photochemical Reactions ; Sulfur-Based Synthesis Techniques
Authors: Jorge S. Gancheff | Florencia Luzardo | Natalia Álvarez | Karolina Soca Rosas | Carlos Kremer | Andréa Simone Stucchi de Camargo
Source: Journal of Transition Metal Complexes (article, 2021-01-01)
Field: Chemistry — Organic Chemistry

Polynuclear 2D Copper(II) Complex of Pyrazine Containing Perchlorate As a Counter-Ion: Crystal Structure and DFT Calculations A new polynuclear cationic complex of copper(II) (Cu(II)) with pyrazine as a ligand and perchlorate acting as a counter-ion was obtained. X-ray diffraction results accounted for a 2D polymer array of cations, in which the metal-ions were located on an ideal squarepyramidal coordination environment defined by four nitrogen atoms of pyrazines and one chloride. The polymer compound, which extended along the ab plane of the structure, showed Cu(II) displaced 0.9 from the plane defined by the N-atoms and chloride. Perchlorate ions were situated in cavities interacting with pyrazine by anion- weak interactions. These low-energy bonds emerged as a consequence of the -acidity of pyrazine upon coordination to Cu(II). Density-functional theory (DFT) calculations at the M06-2X level of theory using 6-31G(d) and 6-31+G(d) were conducted aimed at achieving an electronic description of selected properties of title complex. M06-2X/6-31G(d), in particular, proved to be an acceptable performer in dealing with geometric aspects keeping the computational cost very low. Pyrazine ; Copper ; Perchlorate ; Crystal structure ; Ion ; Crystallography ; Chemistry ; Inorganic chemistry ; Stereochemistry ; Organic chemistry Synthesis and Characterization of Heterocyclic Compounds ; Metal-Organic Frameworks: Synthesis and Applications ; Crystallography and molecular interactions
Authors: Longyu Li
Source: Scholarworks (University of Massachusetts Amherst) (article, 2021-04-01)
Field: Chemistry — Organic Chemistry

Responsive Supramolecular Assemblies Based on Amphiphilic Polymers and Hybrid Materials Cloud platforms have emerged as the primary data warehouse for a variety of applications, such as DropBox, iCloud, Google Music, etc. These applications allow users to store data in the cloud and access it from anywhere in the world. Commercial clouds are also well suited for providing high-end servers for rent to execute applications that require computation resources sporadically. Cloud users only pay for the time they actually use the hardware and the amount of data that is transmitted to and from the cloud, which has the potential to be more cost effective than purchasing, hosting, and maintaining dedicated hardware. In this dissertation, we look into the efficiency of the cloud Infrastructure-as-a-Service (IaaS) model for two real time high bandwidth applications: A scientific application of short-term weather forecasting and Video on Demand services. We show that, cloud services are efficient in both network and computation for real time scientific application of weather forecasting. We present a related list reordering approach, which reduces the network traffic of serving videos from VoD services and improve the efficiency of caches deployed to serve them. Also, we present transcoding policies to reduce the transcoding workload and present prediction models to maintain performance of providing ABR streaming of VoD services at the client with online transcoding in the cloud. Amphiphile ; Supramolecular chemistry ; Supramolecular polymers ; Polymer ; Polymer science ; Nanotechnology ; Materials science ; Chemistry ; Copolymer ; Organic chemistry ; Molecule ; Composite material Advanced Polymer Synthesis and Characterization ; Advanced Theoretical and Applied Studies in Material Sciences and Geometry ; Supramolecular Self-Assembly in Materials
Authors: Sossina Gezahegn
Source:  (preprint, 2021-05-22)
Field: Chemistry — Organic Chemistry

π-Conjugated Heteroles Containing Group 13 Elements This research targeted the synthesis of group 13 neutral heteroles via transmetallation of the tin atom in stannole moieties. The synthesis of Heteroles of 15a (1-chloro-2,3,4,5-tetraphenylborole), 15b (1-chloro-2,3,4,5-tetraphenylaluminole) and 15c (1-chloro-2,3,4,5-tetraphenylgallole) were attempted. The potential formation of Lewis base adducts were explored through the addition of a coordinating solvent of THF, Et3N, and Et2O and characterized with NMR (1H, 13C and 11B where applicable). It was attempted to synthesize Polymer 17a from the di-brominated borole monomer 16a via a Pd-catalyzed polycondensation reaction. THF was subsequently added to the polymer in an attempt to produce the polymer adduct 17a·THF. This was performed to produce a stable enough material for GPC analysis. The polymer was also characterized with NMR. Theoretical calculations were undertaken at the B3LYP/6-31G* level of DFT to help identify the effect of HOMO-LUMO energy gap of the above heteroles and their adducts. DFT calculations reveal that monomers and oligomer energy gaps can be tuned by substituents attached to the heterole, the type of Lewis adduct formed and the degree of catenation. These monomers and oligomers could potentially be novel building blocks for the synthesis of small energy gap π-conjugated systems. Monomer ; Conjugated system ; Chemistry ; Adduct ; Main group element ; Lewis acids and bases ; Oligomer ; Polymer chemistry ; Condensation polymer ; Polymer ; Transmetalation ; Solvent ; Organic chemistry ; Catalysis ; Transition metal Organoboron and organosilicon chemistry ; Chemical Synthesis and Reactions ; Conducting polymers and applications