238 results match your criteria Acs Catalysis[Journal]


Dehydropolymerization of HB·NMeH Using a [Rh(DPEphos)] Catalyst: The Promoting Effect of NMeH.

ACS Catal 2019 Apr 11;9(4):3657-3666. Epub 2019 Mar 11.

Chemistry Research Laboratories, Mansfield Road, University of Oxford, Oxford OX1 3TA, United Kingdom.

[Rh(κ-PP-DPEphos){ηη-HB(NMe)(CH)Bu}][BAr] acts as an effective precatalyst for the dehydropolymerization of HB·NMeH to form -methylpolyaminoborane (HBNMeH) . Control of polymer molecular weight is achieved by variation of precatalyst loading (0.1-1 mol %, an inverse relationship) and use of the chain-modifying agent H: with ranging between 5 500 and 34 900 g/mol and between 1. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.9b00081
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http://dx.doi.org/10.1021/acscatal.9b00081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6454579PMC
April 2019
1 Read

A Parsimonious Mechanism of Sugar Dehydration by Human GDP-Mannose-4,6-dehydratase.

ACS Catal 2019 Apr 1;9(4):2962-2968. Epub 2019 Mar 1.

Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, 8010 Graz, Austria.

Biosynthesis of 6-deoxy sugars, including l-fucose, involves a mechanistically complex, enzymatic 4,6-dehydration of hexose nucleotide precursors as the first committed step. Here, we determined pre- and postcatalytic complex structures of the human GDP-mannose 4,6-dehydratase at atomic resolution. These structures together with results of molecular dynamics simulation and biochemical characterization of wildtype and mutant enzymes reveal elusive mechanistic details of water elimination from GDP-mannose C5″ and C6″, coupled to NADP-mediated hydride transfer from C4″ to C6″. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.9b00064
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http://dx.doi.org/10.1021/acscatal.9b00064DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6454399PMC
April 2019
1 Read

Directing the Outcome of CO Reduction at Bismuth Cathodes Using Varied Ionic Liquid Promoters.

ACS Catal 2018 Apr 2;8(4):2857-2863. Epub 2018 Mar 2.

Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States.

Ionic liquids (ILs) have been established as effective promoters for the electrocatalytic upconversion of CO to various commodity chemicals. Imidazolium ([Im]) cathode combinations have been reported to selectively catalyze the 2e/2H reduction of CO to CO. Recently our laboratory has reported energy-efficient systems for CO production featuring inexpensive bismuth-based cathode materials and ILs comprised of 1,3-dialkylimidazolium cations. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.7b03433
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http://dx.doi.org/10.1021/acscatal.7b03433DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6457684PMC
April 2018
2 Reads

Catalytic Asymmetric Mannich Reaction of α-Fluoronitriles with Ketimines: Enantioselective and Diastereodivergent Construction of Vicinal Tetrasubstituted Stereocenters.

ACS Catal 2019 Mar 6;9(3):2169-2176. Epub 2019 Feb 6.

Department of Chemistry, Georgetown University, 37th and O Streets, Washington, DC 20057, USA.

Diastereodivergent and enantioselective conversion of isatin ketimines to α-fluoro-β-aminonitriles with vicinal tetrasubstituted stereocenters is achieved by a chiral copper complex/guanidine base catalyzed Mannich reaction with proper choice of the bisphosphine ligand. The reaction is broad in scope, scalable, and provides efficient access to a series of 3-aminoindolinones exhibiting a quaternary carbon-fluorine stereocenter with high yields and stereoselectivities. Selective transformations of the Mannich reaction products into multifunctional 3-aminooxindoles without erosion of enantiomeric and diastereomeric purity highlight the synthetic utility. Read More

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http://dx.doi.org/10.1021/acscatal.8b05164DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6449049PMC
March 2019
1 Read

Analysis of Interdependent Kinetic Controls of Fatty Acid Synthases.

ACS Catal 2018 Dec 31;8(12):11722-11734. Epub 2018 Oct 31.

Department of Chemical and Biological Engineering, University of Colorado, Boulder, 3415 Colorado Avenue, Boulder, Colorado 80303, United States.

Biocatalytic systems (e.g., multienzyme pathways or complexes) enable the conversion of simple sugars into complex products under ambient conditions and, thus, represent promising platforms for the synthesis of renewable fuels and chemicals. Read More

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http://dx.doi.org/10.1021/acscatal.8b03171DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6415943PMC
December 2018

Enhanced Catalytic Activity of Nickel Complexes of an Adaptive Diphosphine-Benzophenone Ligand in Alkyne Cyclotrimerization.

ACS Catal 2019 Mar 31;9(3):2458-2481. Epub 2019 Jan 31.

Utrecht University, Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.

Adaptive ligands, which can adapt their coordination mode to the electronic structure of various catalytic intermediates, offer the potential to develop improved homogeneous catalysts in terms of activity and selectivity. 2,2'-Diphosphinobenzophenones have previously been shown to act as adaptive ligands, the central ketone moiety preferentially coordinating reduced metal centers. Herein, the utility of this scaffold in nickel-catalyzed alkyne cyclotrimerization is investigated. Read More

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http://dx.doi.org/10.1021/acscatal.8b05025DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6400243PMC
March 2019
4 Reads

What Is Measured When Measuring Acidity in Zeolites with Probe Molecules?

ACS Catal 2019 Feb 8;9(2):1539-1548. Epub 2019 Jan 8.

Instituto de Tecnología Química, Universitat Politècnica de València - Consejo Superior de Investigaciones Cientificas, Av. de los Naranjos, s/n, 46022 Valencia, Spain.

Based on theoretical calculations of CO, NH, and pyridine adsorption at different sites in MOR and MFI zeolites, we analyze how confinement effects influence the measurement of acidity based on the interaction of probe molecules with Brönsted acid sites. Weak bases, such as CO, form neutral ZH-CO adducts with a linear configuration that can be distorted by spatial restrictions associated with the dimensions of the pore, leading to weaker interaction, but can also be stabilized by dispersion forces if a tighter fitting with the channel void is allowed. Strong bases such as NH and pyridine are readily protonated on Brönsted acid sites, and the experimentally determined adsorption enthalpies include not only the thermochemistry associated with the proton transfer process itself, but also the stabilization of the Z-BH ion pair formed upon protonation by multiple interactions with the surrounding framework oxygen atoms, leading in some cases to a heterogeneity of acidities within the same zeolite structure. Read More

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http://dx.doi.org/10.1021/acscatal.8b04317DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369611PMC
February 2019

Straightforward Regeneration of Reduced Flavin Adenine Dinucleotide Required for Enzymatic Tryptophan Halogenation.

ACS Catal 2019 Feb 4;9(2):1389-1395. Epub 2019 Jan 4.

Organic and Bioorganic Chemistry, Department of Chemistry, and Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, P.O. Box 100131, 33501 Bielefeld, Germany.

Flavin-dependent halogenases are known to regioselectively introduce halide substituents into aromatic moieties, for example, the indole ring of tryptophan. The process requires halide salts and oxygen instead of molecular halogen in the chemical halogenation. However, the reduced cofactor flavin adenine dinucleotide (FADH) has to be regenerated using a flavin reductase. Read More

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http://dx.doi.org/10.1021/acscatal.8b04500DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369659PMC
February 2019
1 Read

Spectroscopic Investigation of the Activation of a Chromium-Pyrrolyl Ethene Trimerization Catalyst.

ACS Catal 2019 Feb 20;9(2):1197-1210. Epub 2018 Dec 20.

Sustainable Materials Characterization, van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.

1-Hexene is an important α-olefin for polyethylene production and is produced from ethene. Recent developments in the α-olefin industry have led to the successful commercialization of ethene trimerization catalysts. An important industrially applied ethene trimerization system uses a mixture of chromium 2-ethylhexanoate, AlEt, AlEtCl, and 2,5-dimethylpyrrole (DMP). Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b03414
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http://dx.doi.org/10.1021/acscatal.8b03414DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369658PMC
February 2019
6 Reads

Expanding the Spectrum of Light-Driven Peroxygenase Reactions.

ACS Catal 2019 Feb 18;9(2):890-894. Epub 2018 Dec 18.

Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.

Peroxygenases require a controlled supply of HO to operate efficiently. Here, we propose a photocatalytic system for the reductive activation of ambient O to produce HO which uses the energy provided by visible light more efficiently based on the combination of wavelength-complementary photosensitizers. This approach was coupled to an enzymatic system to make formate available as a sacrificial electron donor. Read More

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http://dx.doi.org/10.1021/acscatal.8b03752DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369655PMC
February 2019
9.312 Impact Factor

Mechanistic Insight into the [4 + 2] Diels-Alder Cycloaddition over First Row d-Block Cation-Exchanged Faujasites.

ACS Catal 2019 Jan 27;9(1):376-391. Epub 2018 Nov 27.

Inorganic Materials Chemistry group, Department of Chemical Engineering, and Energy Technology, Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.

The Diels-Alder cycloaddition (DAC) is a powerful tool to construct C-C bonds. The DAC reaction can be accelerated in several ways, one of which is reactant confinement as observed in supramolecular complexes and Diels-Alderases. Another method is altering the frontier molecular orbitals (FMOs) of the reactants by using homogeneous transition-metal complexes whose active sites exhibit d-orbitals suitable for net-bonding orbital interactions with the substrates. Read More

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http://dx.doi.org/10.1021/acscatal.8b03482DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369662PMC
January 2019
1 Read

Selective Production of Biobased Phenol from Lignocellulose-Derived Alkylmethoxyphenols.

ACS Catal 2018 Dec 22;8(12):11184-11190. Epub 2018 Oct 22.

Schuit Institute of Catalysis, Inorganic Materials Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.

Lignocellulosic biomass is the only renewable source of carbon for the chemical industry. Alkylmethoxyphenols can be obtained in good yield from woody biomass by reductive fractionation, but these compounds are of limited value for large-scale applications. We present a method to convert lignocellulose-derived alkylmethoxyphenols to phenol that can be easily integrated in the petrochemical industry. Read More

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http://dx.doi.org/10.1021/acscatal.8b03430DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369661PMC
December 2018

Enantioselective Synthesis of Pharmaceutically Active γ-Aminobutyric Acids Using a Tailor-Made Artificial Michaelase in One-Pot Cascade Reactions.

ACS Catal 2019 Feb 7;9(2):1503-1513. Epub 2019 Jan 7.

Department of Chemical and Pharmaceutical Biology, Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.

Chiral γ-aminobutyric acid (GABA) analogues represent abundantly prescribed drugs, which are broadly applied as anticonvulsants, as antidepressants, and for the treatment of neuropathic pain. Here we report a one-pot two-step biocatalytic cascade route for synthesis of the pharmaceutically relevant enantiomers of γ-nitrobutyric acids, starting from simple precursors (acetaldehyde and nitroalkenes), using a tailor-made highly enantioselective artificial "Michaelase" (4-oxalocrotonate tautomerase mutant L8Y/M45Y/F50A), an aldehyde dehydrogenase with a broad non-natural substrate scope, and a cofactor recycling system. We also report a three-step chemoenzymatic cascade route for the efficient chemical reduction of enzymatically prepared γ-nitrobutyric acids into GABA analogues in one pot, achieving high enantiopurity (e. Read More

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http://dx.doi.org/10.1021/acscatal.8b04299DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6366683PMC
February 2019

Catalytic, Enantioselective Synthesis of Allenyl Boronates.

ACS Catal 2018 Apr 21;8(4):3650-3654. Epub 2018 Mar 21.

Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA 92037.

A method to achieve enantioselective 1,4-hydroboration of terminal enynes to access allenyl boronates under CuH catalysis is described. The reaction typically proceeds in a highly stereoselective manner and tolerates an array of synthetically useful functional groups. The utility of the enantioenriched allenyl boronate products is demonstrated through several representative downstream derivatizations. Read More

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http://dx.doi.org/10.1021/acscatal.8b00626DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6364988PMC
April 2018
5 Reads

Cobalt Pincer Complexes in Catalytic C-H Borylation: The Pincer Ligand Flips Rather Than Dearomatizes.

ACS Catal 2018 Nov 17;8(11):10606-10618. Epub 2018 Oct 17.

Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA.

The mechanism for the borylation of an aromatic substrate by a cobalt pincer complex was investigated by density functional theory calculations. Experimental observations identified -(PNP)CoH(BPin) as the resting state in the borylation of five-membered heteroarenes, and 4-BPin-(PNP)Co(N)BPin as the resting state in the catalytic borylation of arene substrates. The active species, 4-R-(PNP)CoBPin (R=H, BPin), were generated by reductive elimination of H in the former, through Berry pseudorotation to the isomer, and N loss in the latter. Read More

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http://dx.doi.org/10.1021/acscatal.8b03146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6358283PMC
November 2018
1 Read

Photocatalysis with Reduced TiO: From Black TiO to Cocatalyst-Free Hydrogen Production.

ACS Catal 2019 Jan 30;9(1):345-364. Epub 2018 Nov 30.

Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacký University Olomouc, Šlechtitelů 27, 78371 Olomouc, Czech Republic.

Black TiO nanomaterials have recently emerged as promising candidates for solar-driven photocatalytic hydrogen production. Despite the great efforts to synthesize highly reduced TiO, it is apparent that intermediate degree of reduction (namely, gray titania) brings about the formation of peculiar defective catalytic sites enabling cocatalyst-free hydrogen generation. A precise understanding of the structural and electronic nature of these catalytically active sites is still elusive, as well as the fundamental structure-activity relationships that govern formation of crystal defects, increased light absorption, charge separation, and photocatalytic activity. Read More

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http://dx.doi.org/10.1021/acscatal.8b04068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6344061PMC
January 2019

Side-Chain Pruning Has Limited Impact on Substrate Preference in a Promiscuous Enzyme.

ACS Catal 2018 Dec 30;8(12):11648-11656. Epub 2018 Oct 30.

Department of Biology and Biotechnology, University of Pavia, Via Ferrata 1, 27100, Pavia, Italy.

Detoxifying enzymes such as flavin-containing monooxygenases deal with a huge array of highly diverse xenobiotics and toxic compounds. In addition to being of high physiological relevance, these drug-metabolizing enzymes are useful catalysts for synthetic chemistry. Despite the wealth of studies, the molecular basis of their relaxed substrate selectivity remains an open question. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b03793
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http://dx.doi.org/10.1021/acscatal.8b03793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6345240PMC
December 2018
1 Read

Molecular Dynamics Simulations of a Conformationally Mobile Peptide-Based Catalyst for Atroposelective Bromination.

ACS Catal 2018 Nov 13;8(11):9968-9979. Epub 2018 Sep 13.

Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, USA.

It is widely accepted that structural rigidity is required to achieve high levels of asymmetric induction in catalytic, enantioselective reactions. This fundamental design principle often does not apply to highly selective catalytic peptides that often exhibit conformational heterogeneity. As a result, these complex systems are particularly challenging to study both experimentally and computationally. Read More

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http://dx.doi.org/10.1021/acscatal.8b03563DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6342276PMC
November 2018
1 Read

Mechanistic Studies of Fatty Acid Activation by CYP152 Peroxygenases Reveal Unexpected Desaturase Activity.

ACS Catal 2019 Jan 6;9(1):565-577. Epub 2018 Dec 6.

Department of Chemistry, Organic & Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria.

The majority of cytochrome P450 enzymes (CYPs) predominantly operate as monooxygenases, but recently a class of P450 enzymes was discovered, that can act as peroxygenases (CYP152). These enzymes convert fatty acids through oxidative decarboxylation, yielding terminal alkenes, and through α- and β-hydroxylation to yield hydroxy-fatty acids. Bioderived olefins may serve as biofuels, and hence understanding the mechanism and substrate scope of this class of enzymes is important. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b03733
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http://dx.doi.org/10.1021/acscatal.8b03733DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6323616PMC
January 2019
19 Reads

Conformational Intermediate That Controls KPC-2 Catalysis and Beta-Lactam Drug Resistance.

ACS Catal 2018 Apr 21;8(4):2741-2747. Epub 2018 Feb 21.

Department of Molecular Physiology and Biological Physics, University of Virginia, Box 800886 Charlottesville VA 22908.

The KPC-2 carbapenemase enzyme is responsible for drug resistance in the majority of carbapenem-resistant gram-negative bacterial infections in the United States. A better understanding of what permits KPC-2 to hydrolyze carbapenem antibiotics and how this might be inhibited is thus of fundamental interest and great practical importance to development of better anti-infectives. By correlating molecular dynamics simulations with experimental enzyme kinetics, we have identified conformational changes that control KPC-2's ability to hydrolyze carbapenem antibiotics. Read More

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http://dx.doi.org/10.1021/acscatal.7b03832DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6324736PMC
April 2018
1 Read

Palladium Catalyzed -C-H Functionalization of Masked Aromatic Aldehydes.

ACS Catal 2018 Aug 5;8(8):7362-7367. Epub 2018 Jul 5.

Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037.

Palladium catalyzed -C-H functionalization enabled by transient mediators has the potential to extend the utility of directed C-H functionalization to remote positions. However, there have been no reports of palladium catalyzed C-H functionalization of aromatic aldehyde derivatives, which are highly versatile intermediates in organic synthesis. Herein we report the development of a directing group that, in the presence of a norbornene derived mediator and an appropriate pyridone ligand, allows palladium catalyzed C-H functionalization of masked aromatic aldehydes. Read More

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http://dx.doi.org/10.1021/acscatal.8b01599DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301045PMC

Catalytic Silylation of Dinitrogen by a Family of Triiron Complexes.

ACS Catal 2018 Aug 19;8(8):7208-7212. Epub 2018 Jul 19.

Center for Catalysis and Florida Center for Heterocyclic Chemistry, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA.

A series of triiron complexes supported by a tris(β-diketiminate)cyclophane ( ) catalyze the reduction of dinitrogen to tris(trimethylsilyl)amine using KC and MeSiCl. Employing FeBr affords 83 ± 7 equiv. NH/complex after protonolysis, which is a 50% yield based on reducing equivalents. Read More

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http://dx.doi.org/10.1021/acscatal.8b02021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6296492PMC
August 2018
3 Reads

Fe-mediated HER vs NRR: Exploring Factors that Contribute to Selectivity in PFe(N) (E = B, Si, C) Catalyst Model Systems.

ACS Catal 2018 Feb 3;8(2):1448-1455. Epub 2018 Jan 3.

Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States.

Mitigation of the hydrogen evolution reaction (HER) is a key challenge in selective small molecule reduction catalysis. This is especially true of catalytic nitrogen (N) and carbon dioxide (CO) reduction reactions (NRR and CORR, respectively) using H/e currency. Here we explore, via DFT calculations, three iron model systems, PFe (E = B, Si, C), known to mediate both NRR and HER, but with different selectivity depending on the identity of the auxiliary ligand. Read More

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http://dx.doi.org/10.1021/acscatal.7b03068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6289286PMC
February 2018

Reversible Restructuring of Silver Particles during Ethylene Epoxidation.

ACS Catal 2018 Dec 8;8(12):11794-11800. Epub 2018 Nov 8.

Laboratory of Inorganic Materials Chemistry, Schuit Institute of Catalysis, Eindhoven University of Technology P.O. Box 513, 5600 MB Eindhoven, The Netherlands.

The restructuring of a silver catalyst during ethylene epoxidation under industrially relevant conditions was investigated without and with vinyl chloride (VC) promotion. During non-VC-promoted ethylene epoxidation, the silver particles grow and voids are formed at the surface and in the bulk. Electron tomography highlighted the presence of voids below the Ag surface. Read More

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http://dx.doi.org/10.1021/acscatal.8b03331DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6292700PMC
December 2018

Cu-Catalyzed Decarboxylative Borylation.

ACS Catal 2018 Oct 13;8(10):9537-9542. Epub 2018 Sep 13.

Department of Chemistry, The Scripps Research Institute (TSRI), North Torrey Pines Road, La Jolla, California 92037, United States.

A simple method for the conversion of carboxylic acids to boronic esters via redox-active esters (RAEs) is reported using copper catalysis. The scope of this transformation is broad, and compared with the known protocols available, it represents the most inexpensive, rapid, and operationally simple option. In addition to a full exploration of the scope, a kinetic study was performed to elucidate substrate and reagent concentration dependences. Read More

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http://dx.doi.org/10.1021/acscatal.8b02928DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6257631PMC
October 2018

Enantioselective Synthesis of Biaryl Atropisomers via the Addition of Thiophenols into Aryl-Naphthoquinones.

ACS Catal 2018 Jun 8;8(6):5443-5447. Epub 2018 May 8.

Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States.

We report a cinchona alkaloid catalyzed addition of thiophenol into rapidly interconverting aryl-naphthoquinones, resulting in stable biaryl atropisomers upon reductive methylation. An array of thiophenols and naphthoquinone substrates were evaluated, and we observed selectivities up to 98.5:1. Read More

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http://dx.doi.org/10.1021/acscatal.8b00906DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6238969PMC

Computationally Assisted Mechanistic Investigation and Development of Pd-Catalyzed Asymmetric Suzuki-Miyaura and Negishi Cross-Coupling Reactions for Tetra-Substituted Biaryl Synthesis.

ACS Catal 2018 Nov 20;8(11):10190-10209. Epub 2018 Sep 20.

Chemical Development, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Rd., Ridgefield, CT 06877, USA.

Metal-catalyzed cross-coupling reactions are extensively employed in both academia and industry for the synthesis of biaryl derivatives for applications to both medicine and material science. Application of these methods to prepare tetra--substituted biaryls leads to chiral atropisomeric products that introduces the opportunity to use catalyst-control to develop asymmetric cross-coupling procedures to access these important compounds. Asymmetric Pd-catalyzed Suzuki-Miyaura and Negishi cross-coupling reactions to form tetra--substituted biaryls were studied employing a collection of -chiral dihydrobenzooxaphosphole (BOP) and dihydrobenzoazaphosphole (BAP) ligands. Read More

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http://dx.doi.org/10.1021/acscatal.8b02509DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6234982PMC
November 2018
1 Read

Preparation of Cobalt Nanocrystals Supported on Metal Oxides To Study Particle Growth in Fischer-Tropsch Catalysts.

ACS Catal 2018 Nov 5;8(11):10581-10589. Epub 2018 Oct 5.

Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.

Colloidal synthesis of nanocrystals (NC) followed by their attachment to a support and activation is a promising route to prepare model catalysts for research on structure-performance relationships. Here, we investigated the suitability of this method to prepare well-defined Co/TiO and Co/SiO catalysts for the Fischer-Tropsch (FT) synthesis with high control over the cobalt particle size. To this end, Co-NC of 3, 6, 9, and 12 nm with narrow size distributions were synthesized and attached uniformly on either TiO or SiO supports with comparable morphology and Co loadings of 2-10 wt %. Read More

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http://dx.doi.org/10.1021/acscatal.8b03094DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6219851PMC
November 2018

Hydrogen-Bonding-Assisted Brønsted Acid and Gold Catalysis: Access to Both ()- and ()-1,2-Haloalkenes via Hydrochlorination of Haloalkynes.

ACS Catal 2018 Feb 15;8(2):904-909. Epub 2017 Dec 15.

College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, 2999 North Renmin Lu, Shanghai 201620, China.

We have developed an efficient synthesis of both ()- and ()-chlorohaloalkenes via hydrochlorination of haloalkynes, based on two distinct hydrogen-bond-network-assisted catalytic systems: Brønsted acid catalysis and gold catalysis. Both systems offer high stereoselectivity, good chemical yields, and diverse functional group tolerance. Read More

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http://dx.doi.org/10.1021/acscatal.7b03563DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6207084PMC
February 2018

Carvone-Derived P-Stereogenic Phosphines: Design, Synthesis, and Use in Allene-Imine [3 + 2] Annulation.

ACS Catal 2018 Jun 4;8(6):5188-5192. Epub 2018 May 4.

Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States.

We have prepared a previously unreported family of P-stereogenic [2.2.1] bicyclic chiral phosphines through straightforward syntheses starting from the natural product carvone. Read More

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http://dx.doi.org/10.1021/acscatal.8b01081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6208446PMC

Practical Intermolecular Hydroarylation of Terminal Alkenes via Reductive Heck Coupling.

ACS Catal 2018 Oct 24;8(10):8987-8992. Epub 2018 Aug 24.

Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, California 92037, United States.

The hydroarylation of alkenes is an attractive approach to construct carbon-carbon (C-C) bonds from abundant and structurally diverse starting materials. Herein we report a palladiumcatalyzed reductive Heck hydroarylation of unactivated and heteroatom-substituted terminal alkenes with an array of (hetero)aryl iodides. The reaction is anti-Markovnikov selective and tolerates a wide variety of functional groups on both the alkene and (hetero)aryl coupling partners. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02717
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http://dx.doi.org/10.1021/acscatal.8b02717DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6207086PMC
October 2018
1 Read

Catalytic Role of Conserved Asparagine, Glutamine, Serine, and Tyrosine Residues in Isoprenoid Biosynthesis Enzymes.

ACS Catal 2018 May 6;8(5):4299-4312. Epub 2018 Apr 6.

Industrial Enzymes National Engineering Laboratory, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China.

We report the results of an investigation into the catalytic role of highly conserved amide (asparagine, glutamine) and OH-containing (serine, tyrosine) residues in several prenyltransferases. We first obtained the X-ray structure of cyclolavandulyl diphosphate synthase containing two molecules of the substrate analog dimethylallyl ()-thiolodiphosphate (DMASPP). The two molecules have similar diphosphate group orientations to those seen in other ζ-fold (- head-to-tail and head-to-middle) prenyltransferases with one diphosphate moiety forming a bidentate chelate with Mg in the so-called S1 site (which is typically the allylic binding site in ζ-fold proteins) while the second diphosphate binds to Mg in the so-called S2 site (which is typically the homoallylic binding site in ζ-fold proteins) a single P1O1 oxygen. Read More

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https://www.researchgate.net/publication/324269263_Catalytic
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http://pubs.acs.org/doi/10.1021/acscatal.8b00543
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http://dx.doi.org/10.1021/acscatal.8b00543DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6193494PMC
May 2018
20 Reads

HO Oxidation by Fe-OOH Intermediates and Its Effect on Catalytic Efficiency.

ACS Catal 2018 Oct 6;8(10):9665-9674. Epub 2018 Sep 6.

Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands.

The oxidation of the C-H and C=C bonds of hydrocarbons with HO catalyzed by non-heme iron complexes with pentadentate ligands is widely accepted as involving a reactive Fe=O species such as [(N4Py)Fe=O] formed by homolytic cleavage of the O-O bond of an Fe-OOH intermediate (where N4Py is 1,1-bis(pyridin-2-yl)-,-bis(pyridin-2-ylmethyl)methanamine). We show here that at low HO concentrations the Fe=O species formed is detectable in methanol. Furthermore, we show that the decomposition of HO to water and O is an important competing pathway that limits efficiency in the terminal oxidant and indeed dominates reactivity except where only sub-/near-stoichiometric amounts of HO are present. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02326
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http://dx.doi.org/10.1021/acscatal.8b02326DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179451PMC
October 2018
17 Reads
9.312 Impact Factor

How Chain Length and Branching Influence the Alkene Cracking Reactivity on H-ZSM-5.

ACS Catal 2018 Oct 5;8(10):9579-9595. Epub 2018 Sep 5.

Center for Molecular Modeling, Ghent University, Technologiepark 903, B-9052, Zwijnaarde, Belgium.

Catalytic alkene cracking on H-ZSM-5 involves a complex reaction network with many possible reaction routes and often elusive intermediates. Herein, advanced molecular dynamics simulations at 773 K, a typical cracking temperature, are performed to clarify the nature of the intermediates and to elucidate dominant cracking pathways at operating conditions. A series of C-C alkene intermediates are investigated to evaluate the influence of chain length and degree of branching on their stability. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b01779
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http://dx.doi.org/10.1021/acscatal.8b01779DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179455PMC
October 2018
1 Read

Effect of Saturating the Electrolyte with Oxygen on the Activity for the Oxygen Evolution Reaction.

ACS Catal 2018 Oct 21;8(10):9359-9363. Epub 2018 Aug 21.

Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA, Leiden, The Netherlands.

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http://pubs.acs.org/doi/10.1021/acscatal.8b01447
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http://dx.doi.org/10.1021/acscatal.8b01447DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179456PMC
October 2018
1 Read

Driving Surface Redox Reactions in Heterogeneous Photocatalysis: The Active State of Illuminated Semiconductor-Supported Nanoparticles during Overall Water-Splitting.

ACS Catal 2018 Oct 20;8(10):9154-9164. Epub 2018 Aug 20.

Photocatalytic Synthesis Group, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Meander 229, P.O. Box 217, 7500 AE Enschede, The Netherlands.

Materials used for photocatalytic overall water splitting (POWS) are typically composed of light-absorbing semiconductor crystals, functionalized with so-called cocatalytic nanoparticles to improve the kinetics of the hydrogen and/or oxygen evolution reactions. While function, quantity, and protection of such metal(oxide) nanoparticles have been addressed in the literature of photocatalysis, the stability and transients in the active oxidation-state upon illumination have received relatively little attention. In this Perspective, the latest insights in the active state of frequently applied cocatalysts systems, including Pt, Rh/CrO, or Ni/NiO , will be presented. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02215
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http://dx.doi.org/10.1021/acscatal.8b02215DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179457PMC
October 2018
1 Read

Deactivation Kinetics of Solid Acid Catalyst with Laterally Interacting Protons.

ACS Catal 2018 Oct 16;8(10):9016-9033. Epub 2018 Aug 16.

Process and Energy Department, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft, The Netherlands.

Differences in catalyst deactivation kinetics in solid acid catalysis are studied with catalyst models that allow for lateral interaction between protons. Deactivation of a solid acid catalyst with laterally interacting protons induces inhomogeneity of proton reactivity that develops with time. As a consequence, product selectivity changes and deactivation will accelerate. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b01511
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http://dx.doi.org/10.1021/acscatal.8b01511DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179454PMC
October 2018
13 Reads

Copper-Containing Catalytic Amyloids Promote Phosphoester Hydrolysis and Tandem Reactions.

ACS Catal 2018 Jan 22;8(1):59-62. Epub 2017 Nov 22.

Department of Chemistry, Syracuse University, 111 College Place, Syracuse, NY 13244.

Self-assembly of short de novo designed peptides gives rise to catalytic amyloids capable of facilitating multiple chemical transformations. We show that catalytic amyloids can efficiently hydrolyze paraoxon, a widely used, highly toxic organophosphate pesticide. Moreover, these robust and inexpensive metal-containing materials can be easily deposited on various surfaces producing catalytic flow devices. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.7b03323
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http://dx.doi.org/10.1021/acscatal.7b03323DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6181230PMC
January 2018
17 Reads

Development of de Novo Copper Nitrite Reductases: Where We Are and Where We Need To Go.

ACS Catal 2018 Sep 19;8(9):8046-8057. Epub 2018 Jul 19.

Department of Chemistry, University of Michigan Ann Arbor, Michigan 48109, United States.

The development of redox-active metalloprotein catalysts is a challenging objective of de novo protein design. Within this Perspective we detail our efforts to create a redox-active Cu nitrite reductase (NiR) by incorporating Cu into the hydrophobic interior of well-defined three-stranded coiled coils (3SCCs). The scaffold contains three histidine residues that provide a layer of three nitrogen donors that mimic the type 2 catalytic site of NiR. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02153
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http://dx.doi.org/10.1021/acscatal.8b02153DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6173324PMC
September 2018
2 Reads

Ring Expansion of Bicyclic Methyleneaziridines via Concerted, Near-Barrierless [2,3]-Stevens Rearrangements of Aziridinium Ylides.

ACS Catal 2018 Sep 17;8(9):7907-7914. Epub 2018 Jul 17.

Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States.

The synthesis of densely functionalized azetidinesin a highly stereocontrolled manner is challenging, but interest in the bioactivities of these small heterocycles has stimulated methods for their preparation. We recently reported a one-carbon ring expansion of bicyclic methylene aziridines under dirhodium catalysis capable of delivering enantioenriched azetidines. This work explores this ring expansion using computational and experimental studies. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02206
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http://dx.doi.org/10.1021/acscatal.8b02206DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6173328PMC
September 2018
17 Reads

Iridium Catalysts for Acceptorless Dehydrogenation of Alcohols to Carboxylic Acids: Scope and Mechanism.

ACS Catal 2018 May 26;8(5):3754-3763. Epub 2018 Mar 26.

Donald P. and Katherine B. Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States.

We introduce iridium-based conditions for the conversion of primary alcohols to potassium carboxylates (or carboxylic acids) in the presence of potassium hydroxide and either [Ir(2-PyCH(CHN))(COD)]OTf () or [Ir(2-PyCHPBu)(COD)]OTf (). The method provides both aliphatic and benzylic carboxylates in high yield and with outstanding functional group tolerance. We illustrate the application of this method to a diverse variety of primary alcohols, including those involving heterocycles and even free amines. Read More

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http://dx.doi.org/10.1021/acscatal.8b00105DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6166666PMC

3-Aryl-2,5-Dihydropyrroles via Catalytic Carbonyl-Olefin Metathesis.

ACS Catal 2018 Mar 18;8(3):2006-2011. Epub 2018 Jan 18.

Department of Chemistry, Willard Henry Dow Laboratory, University of Michigan, 930 North University Ave., Ann Arbor, Michigan 48109, United States.

Herein, we describe the development of a synthetic strategy towards chiral 3-pyrrolines based on the design principle of iron(III)-catalyzed carbonyl-olefin metathesis. This approach takes advantage of commercially available amino acids as chiral pool reagents and FeCl as a Lewis acid catalyst. Our strategy is characterized by its operational simplicity, mild reaction conditions and functional group tolerance. Read More

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http://dx.doi.org/10.1021/acscatal.7b03769DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6162066PMC

Structure and Evolution of Confined Carbon Species during Methane Dehydroaromatization over Mo/ZSM-5.

ACS Catal 2018 Sep 15;8(9):8459-8467. Epub 2018 Aug 15.

Laboratory of Inorganic Materials Chemistry, Schuit Institute of Catalysis, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.

Surface carbon (coke, carbonaceous deposits) is an integral aspect of methane dehydroaromatization catalyzed by Mo/zeolites. We investigated the evolution of surface carbon species from the beginning of the induction period until the complete catalyst deactivation by the pulse reaction technique, TGA, C NMR, TEM, and XPS. Isotope labeling was performed to confirm the catalytic role of confined carbon species during MDA. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02491
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http://dx.doi.org/10.1021/acscatal.8b02491DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6156090PMC
September 2018
4 Reads

Nickel(I) Aryl Species: Synthesis, Properties, and Catalytic Activity.

ACS Catal 2018 Mar 13;8(3):2526-2533. Epub 2018 Feb 13.

The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States.

In this work, Ni(I) aryl species that are directly relevant to cross-coupling have been synthesized. Transmetalation of (dppf)NiX (dppf = 1,1'-bis(diphenylphosphino)-ferrocene, X = Cl, Br) with aryl Grignard reagents or aryl boronic acids in the presence of base produces Ni(I) aryl species of the form (dppf)Ni(Ar) (Ar = Ph, -tolyl, 2,6-xylyl, 2,4,6-mesityl, 2,4,6-PrCH). The stability of the Ni(I) aryl species is inversely correlated to the steric bulk on the aryl ligand. Read More

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http://dx.doi.org/10.1021/acscatal.8b00546DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6150472PMC
March 2018
1 Read

Biocatalytic Aldol Addition of Simple Aliphatic Nucleophiles to Hydroxyaldehydes.

ACS Catal 2018 Sep 8;8(9):8804-8809. Epub 2018 Aug 8.

Biological Chemistry Department, Instituto de Química Avanzada de Cataluña IQAC-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.

Asymmetric aldol addition of simple aldehydes and ketones to electrophiles is a cornerstone reaction for the synthesis of unusual sugars and chiral building blocks. We investigated d-fructose-6-phosphate aldolase from (FSA) D6X variants as catalysts for the aldol additions of ethanal and nonfunctionalized linear and cyclic aliphatic ketones as nucleophiles to nonphosphorylated hydroxyaldehydes. Thus, addition of propanone, cyclobutanone, cyclopentanone, or ethanal to 3-hydroxypropanal or ()- or ()-3-hydroxybutanal catalyzed by FSA D6H and D6Q variants furnished rare deoxysugars in 8-77% isolated yields with high stereoselectivity (97:3 dr and >95% ). Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02486
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http://dx.doi.org/10.1021/acscatal.8b02486DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6135579PMC
September 2018
2 Reads

Operando Insights into CO Oxidation on Cobalt Oxide Catalysts by NAP-XPS, FTIR, and XRD.

ACS Catal 2018 Sep 7;8(9):8630-8641. Epub 2018 Aug 7.

Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, Vienna 1060, Austria.

Cobalt oxide CoO has recently emerged as promising, noble metal-free catalyst for oxidation reactions but a better understanding of the active catalyst under working conditions is required for further development and potential commercialization. An operando approach has been applied, combining near ambient (atmospheric) pressure X-ray photoelectron spectroscopy (NAP-XPS), Fourier transform infrared spectroscopy (FTIR), or X-ray diffraction (XRD) with simultaneous catalytic tests of CO oxidation on CoO, enabling one to monitor surface and bulk states under various reaction conditions (steady-state and dynamic conditions switching between CO and O). On the basis of the surface-specific chemical information a complex network of different reaction pathways unfolded: Mars-van-Krevelen (MvK), CO dissociation followed by carbon oxidation, and formation of carbonates. Read More

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http://dx.doi.org/10.1021/acscatal.8b01237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6135594PMC
September 2018
15 Reads

Unraveling the H Promotional Effect on Palladium-Catalyzed CO Oxidation Using a Combination of Temporally and Spatially Resolved Investigations.

ACS Catal 2018 Sep 26;8(9):8255-8262. Epub 2018 Jul 26.

School of Chemistry and Chemical Engineering, Queen's University Belfast, Stranmillis Road, Belfast BT9 5AG, U.K.

The promotional effect of H on the oxidation of CO is of topical interest, and there is debate over whether this promotion is due to either thermal or chemical effects. As yet there is no definitive consensus in the literature. Combining spatially resolved mass spectrometry and X-ray absorption spectroscopy (XAS), we observe a specific environment of the active catalyst during CO oxidation, having the same specific local coordination of the Pd in both the absence and presence of H. Read More

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http://dx.doi.org/10.1021/acscatal.8b01509DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6135604PMC
September 2018

Tuning the Electrocatalytic Performance of Ionic Liquid Modified Pt Catalysts for the Oxygen Reduction Reaction via Cationic Chain Engineering.

ACS Catal 2018 Sep 25;8(9):8244-8254. Epub 2018 Jul 25.

Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany.

Modifying Pt catalysts using hydrophobic ionic liquids (ILs) has been demonstrated to be a facile approach for boosting the performance of Pt catalysts for the oxygen reduction reaction (ORR). This work aims to deepen the understanding and initiate a rational molecular tuning of ILs for improved activity and stability. To this end, Pt/C catalysts were modified using a variety of 1-methyl-3-alkylimidazolium bis(trifluoromethanesulfonyl)imide ([C Cim][NTf], = 2-10) ILs with varying alkyl chain lengths in imidazolium cations, and the electrocatalytic properties (e. Read More

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http://pubs.acs.org/doi/10.1021/acscatal.8b02018
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http://dx.doi.org/10.1021/acscatal.8b02018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6135603PMC
September 2018
3 Reads
9.312 Impact Factor

Mechanistic Complexity of Methane Oxidation with HO by Single-Site Fe/ZSM-5 Catalyst.

ACS Catal 2018 Sep 18;8(9):7961-7972. Epub 2018 Jul 18.

Catalysis Engineering Group, Chemical Engineering Department, and Inorganic Systems Engineering Group, Chemical Engineering Department, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.

Periodic density functional theory (DFT) calculations were carried out to investigate the mechanism of methane oxidation with HO over the defined Fe sites in Fe/ZSM-5 zeolite. The initial Fe site is modeled as a [(HO)-Fe(III)-(μO)-Fe(III)-(HO)] extraframework cluster deposited in the zeolite pore and charge-compensated by two anionic lattice sites. The activation of this cluster with HO gives rise to the formation of a variety of Fe(III)-oxo and Fe(IV)-oxo complexes potentially reactive toward methane dissociation. Read More

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http://dx.doi.org/10.1021/acscatal.8b01672DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6135593PMC
September 2018
1 Read

Achieving High Ortho Selectivity in Aniline C-H Borylations by Modifying Boron Substituents.

ACS Catal 2018 Jul 9;8(7):6216-6223. Epub 2018 May 9.

Division of Molecular Synthesis & Drug Discovery, Centre of Bio-Medical Research (CBMR), SGPGIMS Campus, Raebareli Road, Lucknow 226 014, UP, India.

High ortho selectivity for Ir-catalyzed C-H borylations (CHBs) of anilines results when Beg (eg = ethylene glycolate) is used as the borylating reagent in lieu of Bpin, which is known to give isomeric mixtures with anilines lacking a blocking group at the 4-position. With this modification, high selectivities and good yields are now possible for various anilines, including those with groups at the 2- and 3-positions. Experiments indicate that ArylN(H)Beg species are generated prior to CHB and support the improved ortho selectivity relative to Bpin reactions arising from smaller Beg ligands on the Ir catalyst. Read More

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http://dx.doi.org/10.1021/acscatal.8b00641DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6105271PMC
July 2018
12 Reads