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1. Catalytic Carbonyl-Olefin Metathesis of Aliphatic Ketones: Iron(III) Homo-Dimers as Lewis Acidic Superelectrophiles

Author:
Albright, Haley; Riehl, Paul S.; McAtee, Christopher C.; Reid, Jolene P.; Ludwig, Jacob R.; Karp, Lindsey A.; Zimmerman, Paul M.; Sigman, Matthew S.; Schindler, Corinna S.
Source:
Journal of the American Chemical Society 2018 v.141 no.4 pp. 1690-1700
ISSN:
1520-5126
Subject:
Lewis acids; catalysts; catalytic activity; chemical bonding; iron; ketones
Abstract:
... Catalytic carbonyl-olefin metathesis reactions have recently been developed as a powerful tool for carbon–carbon bond formation. However, currently available synthetic protocols rely exclusively on aryl ketone substrates while the corresponding aliphatic analogs remain elusive. We herein report the development of Lewis acid-catalyzed carbonyl-olefin ring-closing metathesis reactions for aliphatic ...
DOI:
10.1021/jacs.8b11840
PubMed:
30596414
PubMed Central:
PMC6532644

2. Engineering Oxygen Vacancies into LaCoO₃ Perovskite for Efficient Electrocatalytic Oxygen Evolution

Author:
Lu, Yao; Ma, Aijing; Yu, Yifu; Tan, Rui; Liu, Chengwei; Zhang, Peng; Liu, Dan; Gui, Jianzhou
Source:
ACS sustainable chemistry & engineering 2018 v.7 no.3 pp. 2906-2910
ISSN:
2168-0485
Subject:
active sites; catalysts; catalytic activity; engineering; oxygen; oxygen production; strontium
Abstract:
... Oxygen vacancies (OVs) can improve catalytic activities in oxygen evolution reaction (OER). Although considerable effort has been devoted to increasing the OVs concentration in electrocatalysts, limited OVs have been created by current techniques so far. Here, we, for the first time, engineered (i.e., created) abundant OVs into perovskites by element doping and plasma treatment. The results reveal ...
DOI:
10.1021/acssuschemeng.8b05717

3. First-Row Transition Metal (De)Hydrogenation Catalysis Based On Functional Pincer Ligands

Author:
Alig, Lukas; Fritz, Maximilian; Schneider, Sven
Source:
Chemical reviews 2018 v.119 no.4 pp. 2681-2751
ISSN:
1520-6890
Subject:
catalysts; catalytic activity; dehydrogenation; electrons; hydrogen; hydrogenation; ligands; metals; protons
Abstract:
... The use of 3d metals in de/hydrogenation catalysis has emerged as a competitive field with respect to “traditional” precious metal catalyzed transformations. The introduction of functional pincer ligands that can store protons and/or electrons as expressed by metal–ligand cooperativity and ligand redox-activity strongly stimulated this development as a conceptual starting point for rational cataly ...
DOI:
10.1021/acs.chemrev.8b00555

4. Lewis Acid–Base Synergistic Catalysis for Polyethylene Terephthalate Degradation by 1,3-Dimethylurea/Zn(OAc)₂ Deep Eutectic Solvent

Author:
Liu, Bo; Fu, Wenzhao; Lu, Xingmei; Zhou, Qing; Zhang, Suojiang
Source:
ACS sustainable chemistry & engineering 2018 v.7 no.3 pp. 3292-3300
ISSN:
2168-0485
Subject:
active sites; biodegradation; catalysts; catalytic activity; energy; ethylene glycol; glycolysis; models; polyethylene terephthalates; salts; solvents; synergism; toxicity; urea; zinc
Abstract:
... Deep eutectic solvents (DESs) become more attractive in the catalytic field due to their biodegradation, low toxicity, and designability. This study focused on the active sites and influencing factors of 1,3-dimethylurea (1,3-DMU) based DESs in the polyethylene terephthalate (PET) glycolysis process. It is found that the active site of urea derivatives is the amino group, and the basicity and ster ...
DOI:
10.1021/acssuschemeng.8b05324

5. Selective Production of Propylene from Methanol over Monolith-Supported Modified ZSM-5 Catalysts

Author:
Ali, Mohammad Ashraf; Al-Baghli, Nadhir A.; Nisar, Mohammad; Malaibari, Zuhair O.; Abutaleb, Ahmed; Ahmed, Shakeel
Source:
Energy & fuels 2018 v.33 no.2 pp. 1458-1466
ISSN:
1520-5029
Subject:
X-ray diffraction; catalysts; catalytic activity; coatings; desorption; fuels; iron; liquids; methanol; phosphorus; pollution load; propylene; zeolites
Abstract:
... The catalytic activity of ZSM-5 zeolites with a SiO₂/Al₂O₃ molar ratio of 30, 50, 80, 280, and 410 was investigated in a fixed bed continuous flow reactor system and was found that the ZSM-5 zeolite with SiO₂/Al₂O₃ molar ratio of 280 (HZ-280) exhibited best catalyst performance. The optimized reaction conditions achieved were 500 °C, 1 bar pressure, and weight hourly space velocity of 15 h–¹ using ...
DOI:
10.1021/acs.energyfuels.8b04020

6. Oxygen reduction reaction activity and the microbial community in response to magnetite coordinating nitrogen-doped carbon catalysts in bioelectrochemical systems

Author:
Zhou, Huihui; Yang, Yang; You, Shijie; Liu, Bingfeng; Ren, Nanqi; Xing, Defeng
Source:
Biosensors & bioelectronics 2018 v.122 pp. 113-120
ISSN:
0956-5663
Subject:
Dietzia; active sites; bacterial communities; bioelectrochemistry; biofilm; biosensors; carbon; catalysts; catalytic activity; cathodes; commercialization; electron transfer; genes; hydrogen peroxide; iron; magnetism; magnetite; microbial fuel cells; nitrogen; polymers; porous media; ribosomal RNA
Abstract:
... A Fe-N-C catalyst is supposed to drive commercialization of microbial fuel cells (MFCs) because of its remarkable catalytic performance on oxygen reduction reaction (ORR). However, the catalyst suffers from unclear active site structure and unknown responses of the cathodic microbial community. Here, we prepared a mesoporous core-shell structure catalyst with a nitrogen doped matrix carbon shell, ...
DOI:
10.1016/j.bios.2018.09.044

7. Neutral Au₁-Doped Cluster Catalysts AuTi₂O₃–₆ for CO Oxidation by O₂

Author:
Chen, Jiao-Jiao; Li, Xiao-Na; Chen, Qiang; Liu, Qing-Yu; Jiang, Li-Xue; He, Sheng-Gui
Source:
Journal of the American Chemical Society 2018 v.141 no.5 pp. 2027-2034
ISSN:
1520-5126
Subject:
carbon monoxide; catalysts; catalytic activity; gold; ionization; oxidation; oxygen; spectrometers; titanium dioxide
Abstract:
... Oxide supported gold catalysts (e.g., Au/TiO₂) are of great significance in heterogeneous catalysis owing to their extraordinary catalytic activity. Study of heteronuclear metal oxide clusters (HMOCs, e.g., AuₓTiyOzq) is an important way to uncover the molecular-level mechanisms of gold catalysis in the related heterogeneous catalytic systems. However, the current studies of HMOCs are focused on c ...
DOI:
10.1021/jacs.8b11118

8. Room-Temperature Tandem Condensation-Hydrogenation Catalyzed by Porous C₃N₄ Nanosheet-Supported Pd Nanoparticles

Author:
Nie, Renfeng; Chen, Minda; Pei, Yuchen; Zhang, Biying; Qi, Long; Chen, Jingwen; Goh, Tian Wei; Qi, Zhiyuan; Zhang, Zhiguo; Huang, Wenyu
Source:
ACS sustainable chemistry & engineering 2018 v.7 no.3 pp. 3356-3363
ISSN:
2168-0485
Subject:
ambient temperature; carbon nitride; catalysts; catalytic activity; cyclohexanones; hydrogen; hydrogenation; nanoparticles; nanosheets; nitriles; palladium; surface area
Abstract:
... Tandem catalysis, often inspired by biological systems, offers many advantages in the synthesis of highly functionalized small molecules. NH₂-grafted porous C₃N₄ nanosheet with rich N species and surface area of 138 m²/g was fabricated via a NH₃-exfoliation method. After supporting Pd nanoparticles, the resulting bifunctional catalyst (Pd/C₃N₄–NH₂) could catalyze a one-step tandem condensation-hyd ...
DOI:
10.1021/acssuschemeng.8b05531

9. Aromatic Donor–Acceptor Interaction-Based Co(III)-salen Self-Assemblies and Their Applications in Asymmetric Ring Opening of Epoxides

Author:
Liang, Jian; Soucie, Luke N.; Blechschmidt, Daniel R.; Yoder, Aaron; Gustafson, Addie; Liu, Yu
Source:
Organic letters 2018 v.21 no.2 pp. 513-518
ISSN:
1523-7052
Subject:
catalysts; catalytic activity; chemical reactions; cobalt; crystal structure; epoxides; mass spectrometry; nuclear magnetic resonance spectroscopy
Abstract:
... Aromatic donor–acceptor interaction as the driving force to assemble cooperative catalysts is described. Pyrene/naphthalenediimide functionalized Co(III)-salen complexes self-assembled into bimetallic catalysts through aromatic donor–acceptor interactions and showed high catalytic activity and selectivity in the asymmetric ring opening of various epoxides. Control experiments, nuclear magnetic res ...
DOI:
10.1021/acs.orglett.8b03824

10. Design and Synthesis of Ionic Liquid Supported Hierarchically Porous Zr Metal–Organic Framework as a Novel Brønsted–Lewis Acidic Catalyst in Biodiesel Synthesis

Author:
Ye, Changshen; Qi, Zhaoyang; Cai, Dongren; Qiu, Ting
Source:
Industrial & engineering chemistry process design and development 2018 v.58 no.3 pp. 1123-1132
ISSN:
1520-5045
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; biodiesel; catalysts; catalytic activity; coordination polymers; encapsulation; esterification; ionic liquids; ligands; methanol; nitrogen; oleic acid; process design; response surface methodology; scanning electron microscopy; sulfates; synergism; thermogravimetry; zirconium
Abstract:
... A novel strategy of approximate ligand substitution was proposed to introduce ionic liquids (ILs) into the porous framework of metal–organic frameworks (MOFs). With this approach, an efficient Brønsted–Lewis acidic catalyst [(CH₂COOH)₂IM]HSO₄@H-UiO-66 was successfully constructed via bidentate coordination between one −COO– group of [(CH₂COOH)₂IM]HSO₄ and two portions of unsaturated Zr ion defects ...
DOI:
10.1021/acs.iecr.8b04107

11. Ni(II)-Dimeric Complex-Derived Nitrogen-Doped Graphitized Carbon-Encapsulated Nickel Nanoparticles: Efficient Trifunctional Electrocatalyst for Oxygen Reduction Reaction, Oxygen Evolution Reaction, and Hydrogen Evolution Reaction

Author:
Devi, Bandhana; Koner, Rik Rani; Halder, Aditi
Source:
ACS sustainable chemistry & engineering 2018 v.7 no.2 pp. 2187-2199
ISSN:
2168-0485
Subject:
catalysts; catalytic activity; commercialization; durability; electrochemistry; fuel cells; graphene; hydrogen production; methanol; nanoparticles; nickel; oxygen production; platinum
Abstract:
... The successful commercialization of fuel cells and electrolyzer is limited to the cost and instability issues associated with electrocatalysts (platinum/platinum-based catalysts) used. Hence, there is critical challenge to develop stable, non-platinum-based catalysts with multifunctionality and better durability that can efficiently replace platinum. While a sufficient number of bifunctional catal ...
DOI:
10.1021/acssuschemeng.8b04883

12. Quantitative Evaluation of the Effect of the Hydrophobicity of the Environment Surrounding Brønsted Acid Sites on Their Catalytic Activity for the Hydrolysis of Organic Molecules

Author:
Miura, Hiroki; Kameyama, Shutaro; Komori, Daiki; Shishido, Tetsuya
Source:
Journal of the American Chemical Society 2018 v.141 no.4 pp. 1636-1645
ISSN:
1520-5126
Subject:
Bronsted acids; Fourier transform infrared spectroscopy; X-ray photoelectron spectroscopy; acetate esters; adsorption; catalysts; catalytic activity; ethers; gels; hydrolysis; hydrophobicity; liquids; nuclear magnetic resonance spectroscopy; quantitative analysis; silicon
Abstract:
... Sulfo-functionalized siloxane gels with a variety of surface hydrophobicities were fabricated to elucidate the effect of the environment surrounding the Brønsted acid site on their catalytic activity for the hydrolysis of organic molecules. A detailed structural analysis of these siloxane gels by elemental analysis, X-ray photoelectron spectroscopy, Fourier-transformed infrared (FT-IR), and ²⁹Si M ...
DOI:
10.1021/jacs.8b11471

13. Intramolecular Catalysis in Carboxylic Acid Esterification: Modeling of Single- and Multi-Acid Esterification

Author:
Painer, Daniela; Lux, Susanne
Source:
Industrial & engineering chemistry process design and development 2018 v.58 no.3 pp. 1133-1141
ISSN:
1520-5045
Subject:
acetates; biorefining; catalysts; catalytic activity; dissociation; esterification; formates; formic acid; kinetics; methanol; models; process design; propionic acid; temperature; transesterification
Abstract:
... Downstream processing in the biorefinery is often faced with multicomponent process streams containing carboxylic acids and alcohols. Isolation of carboxylic acids may be simplified by direct esterification with the alcohol present in the process stream. However, uncatalyzed esterification is generally slow at moderate temperature. In multicomponent mixtures, though, stronger carboxylic acids act ...
DOI:
10.1021/acs.iecr.8b04666

14. Manganese-Catalyzed Acceptorless Dehydrogenative Coupling of Alcohols With Sulfones: A Tool To Access Highly Substituted Vinyl Sulfones

Author:
Waiba, Satyadeep; Barman, Milan K.; Maji, Biplab
Source:
Journal of organic chemistry 2018 v.84 no.2 pp. 973-982
ISSN:
1520-6904
Subject:
alcohols; bromides; byproducts; catalysts; catalytic activity; dehydrogenation; iodides; manganese; moieties; nuclear magnetic resonance spectroscopy; organic chemistry
Abstract:
... The development of first-row-transition-metal catalysts that can match with the reactivities of the noble metals is considered to be challenging yet very much a desirable goal in homogeneous catalysis. It has become even more fascinating to develop processes where these metals show a unique reactivity and selectivity than their higher congeners. Herein, we report on the catalytic activity of a pin ...
DOI:
10.1021/acs.joc.8b02911

15. Steric Effect of Protonated Tertiary Amine in Primary–Tertiary Diamine Catalysis: A Double-Layered Sterimol Model

Author:
Wang, Yaning; Zhou, Han; Yang, Kai; You, Chang; Zhang, Long; Luo, Sanzhong
Source:
Organic letters 2018 v.21 no.2 pp. 407-411
ISSN:
1523-7052
Subject:
Gibbs free energy; catalysts; catalytic activity; chemical reactions; enantioselectivity; hydrogen bonding; models; moieties; organic compounds
Abstract:
... Steric shielding effects are seldom adopted in the stereocontrol with chiral primary amine catalysts. An unexpected steric shielding effect of protonated tertiary amine, a typical hydrogen-bonding moiety, was disclosed. A linear free energy relationship between structure and enantioselectivity was established in three reactions when a double-layered Sterimol model was introduced. ...
DOI:
10.1021/acs.orglett.8b03584

16. Thermally Regulated Recyclable Carbene Catalysts for Upgrading of Biomass Furaldehydes

Author:
Cywar, Robin M.; Wang, Lu; Chen, Eugene Y.-X.
Source:
ACS sustainable chemistry & engineering 2018 v.7 no.2 pp. 1980-1988
ISSN:
2168-0485
Subject:
acetates; air; biomass; carbenes; catalysts; catalytic activity; filtration; heterocyclic nitrogen compounds; hydroxymethylfurfural; polyesters; polystyrenes; salts
Abstract:
... The upgrading of biomass furaldehydes—furfural (FF) and 5-alkyl (R) substituted furfurals (R = Me, MF; CH₂OH, HMF; CH₂OMe, MMF)—into C₁₀–₁₄ furoins was achieved by the selective umpolung self-coupling reaction catalyzed by polystyrene (PS) supported azolium salts paired with an acetate counterion, which allows a thermal equilibrium between the dormant ion pair and the active N-heterocyclic carbene ...
DOI:
10.1021/acssuschemeng.8b04190

17. Nanopalladium on Magnetic Ionic Nanoparticle Network (MINN) as an Efficient and Recyclable Catalyst with High Ionic Density and Dispersibility

Author:
Karimi, Babak; Tavakolian, Mina; Mansouri, Fariborz; Vali, Hojatollah
Source:
ACS sustainable chemistry & engineering 2018 v.7 no.4 pp. 3811-3823
ISSN:
2168-0485
Subject:
Suzuki reaction; catalysts; catalytic activity; dispersibility; durability; ionic liquids; ligands; magnetic separation; magnetism; models; nanoparticles; organochlorine compounds; surface area
Abstract:
... A novel magnetic ionic nanoparticle network (MINN) comprising ultrasmall iron oxide nanoparticles as seeds and an immobilized ionic liquid as the interfacing ionic linker was prepared using a simple coupled ligand exchange–sol–gel strategy. The material demonstrated a combination of interesting features such as network structure, high ionic density, pronounced ionic liquid content, excellent redis ...
DOI:
10.1021/acssuschemeng.8b04566

18. Reaction Packaging CoSe₂ Nanoparticles in N-Doped Carbon Polyhedra with Bifunctionality for Overall Water Splitting

Author:
Lu, Hengyi; Zhang, Youfang; Huang, Yunpeng; Zhang, Chao; Liu, Tianxi
Source:
ACS applied materials & interfaces 2018 v.11 no.3 pp. 3372-3381
ISSN:
1944-8252
Subject:
packaging; electrolytes; hydrogen production; porosity; catalysts; carbon; electrolysis; hydrogen; nanoparticles; oxygen production; catalytic activity
Abstract:
... Water electrolysis is a promising approach for green and large-scale hydrogen production; however, there are still challenges for developing efficient and stable bifunctional electrocatalysts toward the hydrogen and oxygen evolution reactions. Herein, zeolitic imidazolate framework-67 was used as the precursor for the construction of CoSe₂ nanoparticles trapped in N-doped carbon (NC) polyhedra. Am ...
DOI:
10.1021/acsami.8b20184

19. Zr-Metal–Organic Frameworks Featuring TEMPO Radicals: Synergistic Effect between TEMPO and Hydrophilic Zr-Node Defects Boosting Aerobic Oxidation of Alcohols

Author:
Zhuang, Jin-Liang; Liu, Xiang-Yue; Zhang, Yu; Wang, Chen; Mao, Hui-Ling; Guo, Jun; Du, Xuan; Zhu, Shao-Bin; Ren, Bin; Terfort, Andreas
Source:
ACS applied materials & interfaces 2018 v.11 no.3 pp. 3034-3043
ISSN:
1944-8252
Subject:
active sites; alcohols; catalysts; catalytic activity; coordination polymers; crystals; free radicals; hydrophilicity; oxidation; synergism
Abstract:
... Metal–organic frameworks (MOFs) featuring multiple catalytic units are excellent platforms for heterogeneous catalysis. However, the synergism between multiple catalytic units for catalysis is far from being well understood. Herein, we reported the synthesis of a robust 2,2,6,6-tetramethylpiperidinyloxy (TEMPO) radical-functionalized Zr-MOF (UiO-68-TEMPO) in the form of single-crystalline and micr ...
DOI:
10.1021/acsami.8b18370

20. Metal–Organic Framework MIL-101-NH₂-Supported Acetate-Based Butylimidazolium Ionic Liquid as a Highly Efficient Heterogeneous Catalyst for the Synthesis of 3-Aryl-2-oxazolidinones

Author:
Chong, S. Y.; Wang, T. T.; Cheng, L. C.; Lv, H. Y.; Ji, M.
Source:
Langmuir 2018 v.35 no.2 pp. 495-503
ISSN:
1520-5827
Subject:
Fourier transform infrared spectroscopy; acetates; butanes; catalysts; catalytic activity; composite materials; coordination polymers; ionic liquids; nitrogen; physicochemical properties; potassium; scanning electron microscopy; ultraviolet-visible spectroscopy
Abstract:
... A novel heterogeneous catalyst, the ionic liquid (IL) of 1-butyl-3-methylimidazolium acetate (BmimOAc) immobilized on MIL-101-NH₂, denoted as IL(OAc–)-MIL-101-NH₂, was prepared by the “ship-in-a-bottle” strategy. The IL of BmimOAc was prepared in the MIL-101-NH₂ nanocages primordially, in which the condensation product of MIL-101-NH₂’s amine group with 1,1′-carbonyldiimidazole (CDI) reacted with 1 ...
DOI:
10.1021/acs.langmuir.8b03153