Chemistry - A European Journal

Cover image for Vol. 23 Issue 35

Editor: Neville Compton, Deputy Editors: Anne Deveson, Elisabeth Roedern

Impact Factor: 5.317

ISI Journal Citation Reports © Ranking: 2016: 29/166 (Chemistry Multidisciplinary)

Online ISSN: 1521-3765

Associated Title(s): Angewandte Chemie International Edition, Chemistry – An Asian Journal, ChemistryOpen, ChemistrySelect, ChemBioChem, ChemCatChem, ChemElectroChem, ChemMedChem, ChemPhotoChem, ChemPhysChem, ChemPlusChem, ChemSusChem, European Journal of Inorganic Chemistry, European Journal of Organic Chemistry

Hot Papers

Hot Papers are chosen by the Editors for their importance in a rapidly evolving field of high current interest. Many of the "Very Important Papers" (VIPs) would certainly qualify to be included here, but such a duplication is avoided.

Sensors

A DNA-Based Label-Free Artificial Tongue for Pattern Recognition of Metal Ions

Hao Qiu, Fang Pu, Xiang Ran, Prof. Dr. Jinsong Ren and Prof. Dr. Xiaogang Qu

A DNA-Based Label-Free Artificial Tongue for Pattern Recognition of Metal Ions

DNA molecules as sensor elements attract considerable interest owing to their unique properties. Here, a label-free sensor array using DNA and commercially available dyes to differentiate metal ions is reported. In this way, fourteen metal ions can be efficiently distinguished by principal component analysis (PCA) and hierarchical cluster analysis (HCA). The work provides a simple and convenient method for the construction of DNA-based sensor arrays.

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Inorganic Flow Chemistry

From Ligand to Phosphor: Rapid, Machine-Assisted Synthesis of Substituted Iridium(III) Pyrazolate Complexes with Tuneable Luminescence

Lara M. Groves, Christiane Schotten, Dr. Joseph Beames, Dr. James A. Platts, Prof. Simon J. Coles, Dr. Peter N. Horton, Dr. Duncan L. Browne and Dr. Simon J. A. Pope

From Ligand to Phosphor: Rapid, Machine-Assisted Synthesis of Substituted Iridium(III) Pyrazolate Complexes with Tuneable Luminescence

Complex Automation: A hybrid approach incorporating continuous-flow and microwave techniques to produce iridium-based phosphors with tunable luminesence and redox properties is reported. Synthesis times are significantly shortened and safety aspects are improved through this method. The novel series of pyrazole-iridium complexes were characterised by physical, photophysical and DFT methods and show tunability in their exhibited properties.

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NMR Spectroscopy

Synthesis of Poly-γ-S-2-methylbutyl-l-glutamate and Poly-γ-S-2-methylbutyl-d-glutamate and Their Use as Enantiodiscriminating Alignment Media in NMR Spectroscopy

Dr. Stefanie Hansmann, Dr. Volker Schmidts and Prof. Dr. Christina M. Thiele

Synthesis of Poly-γ-S-2-methylbutyl-<span class="smallCaps">l</span>-glutamate and Poly-γ-S-2-methylbutyl-<span class="smallCaps">d</span>-glutamate and Their Use as Enantiodiscriminating Alignment Media in NMR Spectroscopy

A perfect match? The synthesis of two diastereomeric polyglutamate derivatives (see scheme) and their application as enantiodiscriminating alignment media for small organic molecules in NMR spectroscopy is described.

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Biological Systems

Artificial Enzyme-based Logic Operations to Mimic an Intracellular Enzyme-participated Redox Balance System

Yanyan Huang, Dr. Fang Pu, Prof. Jinsong Ren and Prof. Xiaogang Qu

Artificial Enzyme-based Logic Operations to Mimic an Intracellular Enzyme-participated Redox Balance System

Of mimes and men: Based on the biocatalytic properties of artificial enzymes and the redox characteristic of glutathione, we designed a colorimetric and resettable biological operation to mimic intracellular enzyme-participated redox balance system. By using four artificial enzymes, three simple biological logic gates were fabricated. With the assistance of glutathione, the system could be easily reset without needing a complicated procedure.

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Enantioselective Separation

Zinc-Coordinated Hierarchical Organization of Ligand-Stabilized Gold Nanoclusters for Chiral Recognition and Separation

Srestha Basu, Prof. Anumita Paul and Prof. Arun Chattopadhyay

Zinc-Coordinated Hierarchical Organization of Ligand-Stabilized Gold Nanoclusters for Chiral Recognition and Separation

Like attracts like: A crystalline complex of zinc ions and gold nanoclusters stabilized with mercaptopropionic acid and d- or l-tryptophan was synthesized. This served as an ideal candidate for facile chiral recognition and separation.

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C−C Coupling

Formaldehyde-Extruding Homolytic Aromatic Substitution via C[RIGHTWARDS ARROW]O Transposition: Selective ‘Traceless-Linker’ access to Congested Biaryl Bonds

Pabhon Poonpatana, Gabriel dos Passos Gomes, Thomas Hurrle, Kimhoa Chardon, Prof. Stefan Bräse, Dr. Kye-Simeon Masters and Prof. Igor Alabugin

Formaldehyde-Extruding Homolytic Aromatic Substitution via C<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/002192.gif" alt="[RIGHTWARDS ARROW]" />O Transposition: Selective ‘Traceless-Linker’ access to Congested Biaryl Bonds

Access denied: Denying the reaction to proceed via the ortho-position (via substituents) in acetal-linked substrates, a C[RIGHTWARDS ARROW]O transposition coupled with the elimination of formaldehyde (as a traceless linker) is achieved. This allows for a new selective way to form C−C bonds and a new synthetic approach towards highly substituted 2-phenyl phenols.

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N-Heterocycles

Synthesis and Characterization of Heterobenzenacyclo-octaphanes Derived from Cyclotetrabenzoin

Sebastian Hahn, Maymounah Alrayyani, Anna Sontheim, Dr. Xiqu Wang, Dr. Frank Rominger, Prof. Dr. Ognjen Š. Miljanić and Prof. Dr. Uwe H. F. Bunz

Synthesis and Characterization of Heterobenzenacyclo-octaphanes Derived from Cyclotetrabenzoin

Colorful rings: Different N-hetero benzenacyclooctaphanes were obtained by condensations with an octaketone building block. We evaluated the optical and electronic properties of the targets and discuss their properties through comparison with their linear diphenyl N-heteroacene counterparts.

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Ligand-based Oxidation

Noninnocent β-Diiminate Ligands: Redox Activity of a Bis(alkylimidazole)methane Ligand in Cobalt and Zinc Complexes

Dr. Pradip Ghosh, Richard Naastepad, Charl F. Riemersma, Dr. Martin Lutz, Dr. Marc-Etienne Moret and Prof. Dr. Robertus J. M. Klein Gebbink

Noninnocent β-Diiminate Ligands: Redox Activity of a Bis(alkylimidazole)methane Ligand in Cobalt and Zinc Complexes

Guilty as charged! Homoleptic transition metal complexes of a new class of β-diiminate ligand can undergo four ligand-based single-electron oxidations in total. The redox non-innocence of the ligand is perceptible by means of single crystal structural analysis.

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Enzyme Catalysis

The Catalytic Mechanism of the Pyridoxal-5′-phosphate-Dependent Enzyme, Histidine Decarboxylase: A Computational Study

Henrique Silva Fernandes, Dr. Maria João Ramos and Dr. Nuno M. F. S. A. Cerqueira

The Catalytic Mechanism of the Pyridoxal-5′-phosphate-Dependent Enzyme, Histidine Decarboxylase: A Computational Study

Role model: The catalytic mechanism of histidine decarboxylase (HDC), a pyridoxal-5′-phosphate (PLP)-dependent enzyme, was studied by using a computational QM/MM approach. The results agree with the available experimental data and allow the role played by several active site residues that are considered relevant according to site-directed mutagenesis studies to be explained.

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Ligand Design

Triazolylidene-Iridium Complexes with a Pendant Pyridyl Group for Cooperative Metal–Ligand Induced Catalytic Dehydrogenation of Amines

Dr. Marta Valencia, Ana Pereira, Dr. Helge Müller-Bunz, Prof. Dr. Tomás R. Belderraín, Prof. Dr. Pedro J. Pérez and Prof. Dr. Martin Albrecht

Triazolylidene-Iridium Complexes with a Pendant Pyridyl Group for Cooperative Metal–Ligand Induced Catalytic Dehydrogenation of Amines

Hang in there! A pendant pyridyl group in the C,N-bidentate chelating carbene-pyridyl complex 1 facilitates amine coordination to the iridium center and enhances catalytic activity of the metal center in amine dehydrogenation. Stoichiometric experiments provide evidence for hydrogen bonding of the amine substrate with the pendant pyridyl unit.

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Organic Diradicals

Thienylquinonoidal Porphyrins and Hexaphyrins with Singlet Diradical Ground States

Koji Naoda, Daiki Shimizu, Jun Oh Kim, Prof. Dr. Ko Furukawa, Prof. Dr. Dongho Kim and Prof. Dr. Atsuhiro Osuka

Thienylquinonoidal Porphyrins and Hexaphyrins with Singlet Diradical Ground States

Radical state: Oligothienylquinonoid-substituted porphyrins Pn and hexaphyrins Hn (n=0–2) were synthesized. P0 has been shown to be a closed-shell quinonoid, whereas P1 has been shown to be a diradical that is sensitive toward air and moisture. H0 and H1 have been shown to be quinonoids, whereas H2 has been characterized as a remarkably stable diradical with singlet ground state owing to the effective spin delocalization over the whole conjugated circuit.

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Cross-Coupling

Metal-Free Direct Alkylation of Ketene Dithioacetals by Oxidative C(sp2)−H/C(sp3)−H Cross-Coupling

Jiangwei Wen, Fan Zhang, Wenyan Shi and Prof. Dr. Aiwen Lei

Metal-Free Direct Alkylation of Ketene Dithioacetals by Oxidative C(sp2)−H/C(sp3)−H Cross-Coupling

A bond-cleavage without metals: This protocol provides an efficient and conventional method to obtain tetrasubstituted olefins. Importantly, the results of mechanistic experiments demonstrate that the alkane C−H bond cleavage is involved in the rate-determining step, and a radical pathway is proposed for the alkylation reaction. Notably, the present protocol has excellent functional group tolerance and could be easily scaled up with good efficiency.

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Biochemistry

2′β-Fluoro-Tricyclo Nucleic Acids (2′F-tc-ANA): Thermal Duplex Stability, Structural Studies, and RNase H Activation

Dr. Alena Istrate, Dr. Adam Katolik, Dr. Andrei Istrate and Prof. Dr. Christian J. Leumann

2′β-Fluoro-Tricyclo Nucleic Acids (2′F-tc-ANA): Thermal Duplex Stability, Structural Studies, and RNase H Activation

Gene in a bottle: The synthesis and biophysical properties of 2′β-fluoro-tricyclo nucleic acids (2′F-tc-ANA) are described. Overall, 2′F-tc-ANA represents a nucleic acid analogue with high RNA affinity while maintaining the ability to activate RNase H, and can be considered a prospective candidate for gene silencing applications.

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Supramolecular chemistry

Stepwise Construction of Self-Assembled Heterometallic Cages Showing High Proton Conductivity

Rupak Saha, Dipak Samanta, Prof. Aninda Jiban Bhattacharyya and Prof. Partha Sarathi Mukherjee

Stepwise Construction of Self-Assembled Heterometallic Cages Showing High Proton Conductivity

Complex cages: A series of discrete self-assembled heterometallic cages was synthesized in stepwise manner. Two of them showed high proton conductivity at a wide temperature range under different humid conditions.

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Molecular Devices

Tuning the Sensitivity of Fluorescent Porphyrin Dimers to Viscosity and Temperature

Dr. Aurimas Vyšniauskas, Dong Ding, Dr. Maryam Qurashi, Igor Boczarow, Dr. Milan Balaz, Prof. Harry L. Anderson and Dr. Marina K. Kuimova

Tuning the Sensitivity of Fluorescent Porphyrin Dimers to Viscosity and Temperature

Red, fluorescent and viscosity-sensitive: A series of viscosity-sensitive fluorophores (“molecular rotors”) based on a porphyrin dimer structure were tested for sensitivity to viscosity and temperature. We demonstrate how both viscosity and temperature can be measured by tuning the structure of the dimers.

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Organocatalysis

Organocatalytic Stereoconvergent Synthesis of α-CF3 Amides: Triketopiperazines and Their Heterocyclic Metamorphosis

Dr. Robert W. Foster, Dr. Eva N. Lenz, Prof. Dr. Nigel S. Simpkins and Dr. Darren Stead

Organocatalytic Stereoconvergent Synthesis of α-CF3 Amides: Triketopiperazines and Their Heterocyclic Metamorphosis

All about that base: The organocatalytic stereoconvergent synthesis of α-CF3 amides has been developed. This approach has been used to access a diverse range of enantioenriched triketopiperazine products and a novel reaction mechanism has been elucidated. In addition, an enamine-mediated rearrangement was developed for the regioselective synthesis of enantiopure semi-saturated pyrazolopyrimidines.

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Metal-Carbon Bonding

Sequential Reactions of Alkynes on an Iridium(III) Single Site

Elena A. Giner, Mar Gómez-Gallego, Alba D. Merinero, Luis Casarrubios, Carmen Ramírez de Arellano and Miguel A. Sierra

Sequential Reactions of Alkynes on an Iridium(III) Single Site

On your iridacycle! Cyclometalated half-sandwich IrIII complexes react with ortho-methyl-substituted aromatic alkynes to form Ir metallacycles resulting from the consecutive assembly of three efficient reactions: C−C bond formation, C(sp3)−H activation, and reductive coupling. The reaction is straightforward and allows for the incorporation of biomolecules (purines), photoactive molecules, and hybrid BODIPY–nucleoside derivatives, and as such are potentially useful for bio-labeling.

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Metal Complexes

Design, Synthesis, and Chemistry of Bis(σ)borate and Agostic Complexes of Group 7 Metals

Koushik Saha, Rongala Ramalakshmi, Suman Gomosta, Kriti Pathak, Vincent Dorcet, Dr. Thierry Roisnel, Prof. Dr. Jean-François Halet and Prof. Dr. Sundargopal Ghosh

Design, Synthesis, and Chemistry of Bis(σ)borate and Agostic Complexes of Group 7 Metals

Let it B: Several borate ligands with group 7 metals that show novel structures, bonding, and reactivities were synthesized. In addition, some bis(σ)borate complexes reacted with phosphines and led to the isolation of isomeric borate complexes (see scheme).

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Helical Structures

Twisting of Alkynes towards a Carbon Double Helix

Abdulselam Adam and Prof. Dr. Gebhard Haberhauer

Twisting of Alkynes towards a Carbon Double Helix

Search for a carbon double helix: Calculations show that only small energetic effort is required for a three-dimensional twisting of oligoalkynes. This kind of three-dimensional twisting could be experimentally proved by the synthesis of model systems in which two diphenyl oligoalkyne chains are fixed and twisted by a chiral imidazole-containing clamp (see figure).

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Supramolecular Chemistry

Arene-Inserted Extended Germa[n]pericyclynes: Synthesis, Structure, and Phosphorescence Properties

Dr. Hiroki Tanimoto, Junta Mori, Shunichiro Ito, Dr. Yasuhiro Nishiyama, Prof. Dr. Tsumoru Morimoto, Prof. Dr. Kazuo Tanaka, Prof. Dr. Yoshiki Chujo and Prof. Dr. Kiyomi Kakiuchi

Arene-Inserted Extended Germa[n]pericyclynes: Synthesis, Structure, and Phosphorescence Properties

A link to the future: This report describes the syntheses of arene-inserted type extended (ArEx) germa[n]pericyclynes composed of germanium-1,4-diethynylbenzene units, and their characterization. These novel cyclic germanium-π unit materials were characterized by X-ray crystallography, UV/Vis spectroscopy, fluorescence, and phosphorescence emission spectroscopy, which showed characteristic optical properties and large emission lifetimes compared to previous derivatives.

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Systems Chemistry

Unraveling the Multistimuli Responses of a Complex Dynamic System of Pseudopeptidic Macrocycles

Dr. Angel M. Valdivielso, Francesc Puig-Castellví, Dr. Joan Atcher, Dr. Jordi Solà, Prof. Dr. Romà Tauler and Dr. Ignacio Alfonso

Unraveling the Multistimuli Responses of a Complex Dynamic System of Pseudopeptidic Macrocycles

Getting a response: A complex dynamic library of macrocycles is responsive to several chemical stimuli, such as the ionic strength, the pH of the medium or the presence of a biogenic polyamine as a substrate. The adaptive responses of the whole dynamic library were unraveled using multivariate data analysis.

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Polymers

Semiconducting Coordination Polymers Based on the Predesigned Ternary Te-Fe-Cu Carbonyl Cluster and Conjugation-Interrupted Dipyridyl Linkers

Prof. Dr. Minghuey Shieh, Chia-Chi Yu, Dr. Chia-Yeh Miu, Chang-Hung Kung, Chung-Yi Huang, Yu-Hsin Liu, Prof. Dr. Hsiang-Lin Liu and Dr. Chih-Chiang Shen

Semiconducting Coordination Polymers Based on the Predesigned Ternary Te-Fe-Cu Carbonyl Cluster and Conjugation-Interrupted Dipyridyl Linkers

Cross the bridge! A series of conjugation-interrupted dipyridyl-linked cluster-incorporated polymers have been synthesized by liquid-assisted grinding. These polymers exhibit surprising semiconducting characteristics with ultra-narrow bandgaps and high conductivities, which violates our knowledge, attributed to the through-space electron transport via non-classical C−H⋅⋅⋅O(carbonyl) hydrogen bonds and aromatic C−H⋅⋅⋅π interactions.

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Fluorination

The Versatile Behavior of Platinum Alkyne Complexes towards XeF2: Formation of Fluorovinyl and Fluorido Complexes

Dr. Josefine Berger, Prof. Dr. Thomas Braun, Dr. Theresia Ahrens, Dr. Paul Kläring, Reik Laubenstein and Dr. Beatrice Braun-Cula

The Versatile Behavior of Platinum Alkyne Complexes towards XeF2: Formation of Fluorovinyl and Fluorido Complexes

What happens with XeF2? Electrophilic fluorination with XeF2 occurs at platinum-bound alkyne ligands to yield platinum(II) β-fluorovinyl fluorido compounds. An excess of XeF2 gives access to platinum(IV) fluoride complexes, but can also lead to fluorinated olefins (see scheme).

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Ionic Liquids

Green Imidazolium Ionics–From Truly Sustainable Reagents to Highly Functional Ionic Liquids

Steffen Tröger-Müller, Jessica Brandt, Prof. Dr. Markus Antonietti and Dr. Clemens Liedel

Green Imidazolium Ionics–From Truly Sustainable Reagents to Highly Functional Ionic Liquids

Task-specific ionic liquids: Highly functional ionic liquids were obtained using a benign reaction from low-cost, potentially green building blocks. Functionalities for applications in electrochemistry, metal complexation, and polymerization are included without hazardous or expensive reagents. Synthesis and analysis are described in detail, and potential applications are outlined.

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Asymmetric Catalysis

Palladium-Catalyzed Enantioselective Alkoxycarbonylation of Propargylic Carbonates with (R)- or (S)-3,4,5-(MeO)3-MeOBIPHEP

Wanli Zhang and Prof. Dr. Shengming Ma

Palladium-Catalyzed Enantioselective Alkoxycarbonylation of Propargylic Carbonates with (R)- or (S)-3,4,5-(MeO)3-MeOBIPHEP

Going left or right? A catalytic highly enantioselective synthesis of 2,3-allenoates from easily available racemic propargylic carbonates utilizing (R)- or (S)-3,4,5-(MeO)3-MeOBIPHEP and Pd has been developed, resulting in optically active allenoates with 90–98 % ee and decent yields.

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Asymmetric Catalysis

Catalytic Enantioselective Arylation and Heteroarylation of Ketones with Organotitanium Reagents Generated In Situ

Atsushi Matsuda, Tomoya Ushimaru, Yusuke Kobayashi and Prof. Dr. Toshiro Harada

Catalytic Enantioselective Arylation and Heteroarylation of Ketones with Organotitanium Reagents Generated In Situ

Titanium from within: A practical method has been developed for the catalytic enantioselective arylation and heteroarylation of ketones using titanium reagents, prepared in situ from inexpensive bromide or heteroarene precursors. Enantioselective preparation of a variety of tertiary diaryl carbinols and aryl heteroaryl carbinols could be achieved with a chiral titanium catalyst derived from a new ligand (R)-BTFP-BINOL at low loading (2 mol %).

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Mesoporous Materials

Fluorogenic Sensing of Carcinogenic Bisphenol A using Aptamer-Capped Mesoporous Silica Nanoparticles

Àngela Ribes, Dr. Elena Aznar, Dr. Andrea Bernardos, Dr. M. Dolores Marcos, Dr. Pedro Amorós, Dr. Ramón Martínez-Máñez and Dr. Félix Sancenón

Fluorogenic Sensing of Carcinogenic Bisphenol A using Aptamer-Capped Mesoporous Silica Nanoparticles

A new hybrid aptamer-capped mesoporous silica material has been developed for the selective and sensitive detection of Bisphenol A in water.

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Halogens

Halogen Bonds in Novel Polyhalogen Monoanions

Dr. Changwei Wang, Dr. David Danovich, Prof. Dr. Sason Shaik and Prof. Dr. Yirong Mo

Halogen Bonds in Novel Polyhalogen Monoanions

Evolution of the halogen bond:The halogen bond in [X2n+1] is primarily covalent due to a n[RIGHTWARDS ARROW]σ* charge-transfer interaction. As expected, covalence is not additive, and it decreases as the cluster size grows. The halogen bond between the [X2n−1] anion and a X2 molecule exhibits the same trends as the X⋅⋅⋅X2 halogen bond at different distance, which can thus be taken as a gauge for all [X2n+1] species.

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Computational Chemistry

How Can Methanol Dehydrogenase from Methylacidiphilum fumariolicum Work with the Alien CeIII Ion in the Active Center? A Theoretical Study

Mario Prejanò, Prof. Tiziana Marino and Prof. Nino Russo

How Can Methanol Dehydrogenase from Methylacidiphilum fumariolicum Work with the Alien CeIII Ion in the Active Center? A Theoretical Study

Ca- vs. Ce-methanol dehydrogenase (MDH): From the comparison with Ca-MDH, it emerges that although the reaction mechanism is the same, the presence of CeIII center favors the formation of the nucleophilic agent and the first produced intermediate is thermodynamically stabilized in Ce-MDH. This result provides the explanation for the different potential energy surface behaviors in the next addition and elimination steps.

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Asymmetric Synthesis

Stereoselective and Enantiospecific Mono- and Bis-C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion-Binding Catalysis

Alessandro Bosmani, Dr. Sandip A. Pujari, Dr. Céline Besnard, Dr. Laure Guénée, Dr. Amalia I. Poblador-Bahamonde and Prof. Jérôme Lacour

Stereoselective and Enantiospecific Mono- and Bis-C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion-Binding Catalysis

Basic instinct: Regio- and stereoselective Csp3−H azidations of Tröger bases are reported. Both mono- and bisazide functionalizations are available using TMSN3 and PhIO as reagent. High enantiospecificity is achieved (es 96–99 %). Interestingly, bridgehead iminium intermediates are evidenced by mechanistic and in-silico studies. With the azido products in hand, tailored bistriazole derivatives were prepared for application in anion-binding catalysis.

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Fluorescent Probes

Rational Development of Near-Infrared Fluorophores with Large Stokes Shifts, Bright One-Photon, and Two-Photon Emissions for Bioimaging and Biosensing Applications

Prof. Dr. Liyi Zhou, Qianqian Wang, Yi Tan, Prof. Dr. Matthew J. Lang, Prof. Dr. Hongyan Sun and Dr. Xiaogang Liu

Rational Development of Near-Infrared Fluorophores with Large Stokes Shifts, Bright One-Photon, and Two-Photon Emissions for Bioimaging and Biosensing Applications

Molecular engineering of near-infrared dyes: A new class of near-infrared fluorophores is reported that exhibit bright two-photon emissions, due to the resonant enhancement effect in the second absorption band of their two-photon absorption (2PA) spectra. Their Stokes shifts were increased by incorporating substitutes which experience slight rotations upon photoexcitation.

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Materials Science

Photocatalytic CO2 Reduction by Periodic Mesoporous Organosilica (PMO) Containing Two Different Ruthenium Complexes as Photosensitizing and Catalytic Sites

Dr. Yusuke Kuramochi, Masato Sekine, Kyohei Kitamura, Yoshifumi Maegawa, Dr. Yasutomo Goto, Dr. Soichi Shirai, Dr. Shinji Inagaki and Prof. Dr. Hitoshi Ishida

Photocatalytic CO2 Reduction by Periodic Mesoporous Organosilica (PMO) Containing Two Different Ruthenium Complexes as Photosensitizing and Catalytic Sites

Two of a kind: A periodic mesoporous organosilica (PMO) containing 2,2′-bipyridine (bpy) ligands within the framework (BPy-PMO) has been modified in a stepwise fashion with two different functional ruthenium complexes to synthesize Ru(PS)-Ru(Cat)-BPy-PMO as a heterogeneous catalyst for photochemical CO2 reduction.

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Asymmetric Catalysis

Catalysis of Michael Additions by Covalently Modified G-Quadruplex DNA

Dr. Surjendu Dey, Carmen L. Rühl and Prof. Andres Jäschke

Catalysis of Michael Additions by Covalently Modified G-Quadruplex DNA

A cat with ten lives: A new class of G-quadruplex DNA-based artificial metalloenzymes was developed and applied in asymmetric Michael addition. It was found that several parameters are all crucial for the catalytic performance. Up to 83 % ee for the product was obtained with the newly synthesized metalloenzymes (see figure) and they could be reused ten times without reduction of stereoselectivity. These findings are highly important as guiding principles for the design of asymmetric DNA-based hybrid catalysts.

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Gold Catalysis

Dual Gold Catalysis: Bidirectional Processes and Tandem sp3-C−H Insertion Reactions

Svetlana Tšupova, Dr. Matthias Rudolph, Dr. Frank Rominger and Prof. Dr. A. Stephen K. Hashmi

Dual Gold Catalysis: Bidirectional Processes and Tandem sp3-C−H Insertion Reactions

Running rings around gold: Gold-catalyzed cyclization of thiophene-based teraynes has been accomplished. The exact structure of the products there depends on the nature of the linker between the two diethynylthiophene moieties.

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Computational Chemistry

Hydrogen-Bond Strength of CC and GG Pairs Determined by Steric Repulsion: Electrostatics and Charge Transfer Overruled

Stephanie C. C. van der Lubbe and Prof. Dr. Célia Fonseca Guerra

Hydrogen-Bond Strength of CC and GG Pairs Determined by Steric Repulsion: Electrostatics and Charge Transfer Overruled

When electrons come too close: The Pauli repulsion can be a decisive factor for relative hydrogen bonding strengths and lengths. This study on DNA base pairs highlights the complex nature of hydrogen bonds, which are an interplay between steric, electrostatic, covalent, cooperative, and π-resonance interactions, and emphasizes the importance of state-of-the-art quantum chemical analysis to shed light on their bonding mechanism.

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N-Heterocyclic Carbenes

Polymer-Supported Palladium(II) Carbene Complexes: Catalytic Activity, Recyclability, and Selectivity in C−H Acetoxylation of Arenes

Maitham H. Majeed, Payam Shayesteh, Prof. L. Reine Wallenberg, Axel R. Persson, Niclas Johansson, Prof. Lei Ye, Prof. Joachim Schnadt and Prof. Ola F. Wendt

Polymer-Supported Palladium(II) Carbene Complexes: Catalytic Activity, Recyclability, and Selectivity in C−H Acetoxylation of Arenes

Again and again: Co-polymerization of divinyl benzene with vinyl moieties in a PdII complex gives a recyclable heterogeneous catalyst that is active in direct acetoxylation of unactivated C−H bonds in arenes and where the selectivity is equal, and in some cases superior, to the corresponding homogenous catalysts.

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Chalcogens

Silyl Chalconium Ions: Synthesis, Structure and Application in Hydrodefluorination Reactions

Dr. Natalie Kordts, Sandra Künzler, Saskia Rathjen, Thorben Sieling, Dr. Henning Großekappenberg, Dr. Marc Schmidtmann and Prof. Dr. Thomas Müller

Silyl Chalconium Ions: Synthesis, Structure and Application in Hydrodefluorination Reactions

Oxygen breaks ranks: The structural, spectroscopic and computer–chemical characterization of two series of silylated chalconium ions (Ch=O, S, Se, Te) revealed significant differences between the second row element oxygen and its higher congeners.

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Transition-Metal Chalcogenides

2H[RIGHTWARDS ARROW]1T Phase Engineering of Layered Tantalum Disulfides in Electrocatalysis: Oxygen Reduction Reaction

Jan Luxa, Vlastimil Mazánek, Prof. Martin Pumera, Dr. Petr Lazar, Prof. David Sedmidubský, Dr. Mauro Callisti, Dr. Tomáš Polcar and Prof. Zdeněk Sofer

2H<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/002192.gif" alt="[RIGHTWARDS ARROW]" />1T Phase Engineering of Layered Tantalum Disulfides in Electrocatalysis: Oxygen Reduction Reaction

The right phase? Transition-metal chalcogenides (TMDs) have promising applications in electrocatalysis. The activity of TMDs 2H TaS2 and 1T TaS2 in the oxygen reduction reaction (ORR) and the hydrogen evolution reaction (HER) have been explored. Both phases showed poor HER activity, but good ORR activity, comparable to that of commercial Pt/C. DFT calculations were used to clarify the surprisingly low HER activity of 1T TaS2.

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Supported Catalysts

Electrosynthesis of Bifunctional WS3−x/Reduced Graphene Oxide Hybrid for Hydrogen Evolution Reaction and Oxygen Reduction Reaction Electrocatalysis

Shu Min Tan and Prof. Martin Pumera

Electrosynthesis of Bifunctional WS3−x/Reduced Graphene Oxide Hybrid for Hydrogen Evolution Reaction and Oxygen Reduction Reaction Electrocatalysis

A trick or two: Bifunctional electrocatalysts of WS3−x supported on reduced graphene oxide (rGO) towards both hydrogen evolution and oxygen reduction reactions (HER and ORR, respectively) are fabricated through simultaneous electrochemical reduction and deposition, as an environmentally benign alternative to conventional fabrication techniques (see figure).

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Multinuclear Complexes

A Fluxional Cu8H6 Cluster Supported by Bis(diphenylphosphino)methane and its Facile Reaction with CO2

Dr. Kanako Nakamae, Miho Tanaka, Dr. Bunsho Kure, Prof. Takayuki Nakajima, Prof. Yasuyuki Ura and Prof. Tomoaki Tanase

A Fluxional Cu8H6 Cluster Supported by Bis(diphenylphosphino)methane and its Facile Reaction with CO2

Copper hydride cluster: An octanuclear complex of [Cu8(μ-H)6(μ-dppm)5](PF6)2 (1), was synthesized by treating [CuH(PPh3)]6 and [Cu(CH3CN)4]PF6 with bis(diphenylphosphino)methane (dppm), and showed interesting scrambling behaviors of the ligands and facile reaction with CO2 to give [Cu3(μ-H)(μ-HCO2)(μ-dppm)3]PF6 (2), which led to catalytic hydrosilylation of CO2 under mild conditions.

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Nanomaterials

A Lanthanide MOF Thin-Film Fixed with Co3O4 Nano-Anchors as a Highly Efficient Luminescent Sensor for Nitrofuran Antibiotics

Feng Zhang, Hua Yao, Tianshu Chu, Gaowei Zhang, Yi Wang and Prof. Yangyi Yang

A Lanthanide MOF Thin-Film Fixed with Co3O4 Nano-Anchors as a Highly Efficient Luminescent Sensor for Nitrofuran Antibiotics

A new detective: A Ln MOF thin-film was fabricated using a nano-anchor fixation method, in which cobalt oxide species serve as the anchor. This material was utilized as a highly selective sensor for the detection of common nitrofuran-based antibiotics.

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Drug Discovery

A Specific and Covalent JNK-1 Ligand Selected from an Encoded Self-Assembling Chemical Library

Dr. Gunther Zimmermann, Dr. Ulrike Rieder, Davor Bajic, Sara Vanetti, Dr. Apirat Chaikuad, Prof. Dr. Stefan Knapp, Dr. Jörg Scheuermann, Dr. Martin Mattarella and Prof. Dr. Dario Neri

A Specific and Covalent JNK-1 Ligand Selected from an Encoded Self-Assembling Chemical Library

A novel covalent binder of JNK1, a kinase containing seven cysteine residues, including a conserved cysteine residue close to the ATP binding site, has been identified from a DNA encoded self-assembling chemical library (ESAC). The binder showed the ability to covalently modify JNK1 in a 1:1 stoichiometry in the presence of a large molar excess of glutathione to mimic the intracellular reducing environment.

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Synthetic Methods

An Aminocatalyzed Stereoselective Strategy for the Formal α-Propargylation of Ketones

Dr. Igor D. Jurberg

An Aminocatalyzed Stereoselective Strategy for the Formal α-Propargylation of Ketones

Add and unmask! Alkylidene isoxazol-5-ones can be used as key building blocks in a stereoselective aminocatalyzed Michael addition/nitrosative alkynylation sequence to produce an overall process of α-propargylation of ketones. This reaction sequence produces moderate to good yields, perfect diastereocontrol and good to excellent enantioselectivity, therefore making this synthetic route a viable strategy for the construction of densely substituted α-propargyl ketones.

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Iodine

Direct Observation of Confined I⋅⋅⋅I2⋅⋅⋅I Interactions in a Metal–Organic Framework: Iodine Capture and Sensing

Yue-Qiao Hu, Mu-Qing Li, Yanyan Wang, Tao Zhang, Dr. Pei-Qin Liao, Prof. Dr. Zhiping Zheng, Prof. Dr. Xiao-Ming Chen and Prof. Dr. Yan-Zhen Zheng

Direct Observation of Confined I−⋅⋅⋅I2⋅⋅⋅I− Interactions in a Metal–Organic Framework: Iodine Capture and Sensing

I2 spy: A heterometallic metal-organic framework {Tb(Cu4I4)(ina)3(DMF)} with 1D {Cu4I4}n building units shows a huge conductivity enhancement by ca. 107 times after uptake of guest iodine molecules, which can be used to sense iodine.

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Actinides

A Spontaneous Structural Transition of {U24Pp12} Clusters Triggered by Alkali Counterion Replacement in Dilute Solution

Yunyi Gao, Mateusz Dembowski, Jennifer E. S. Szymanowski, Wenbin Yin, Prof. Dr. Steven S. C. Chuang, Prof. Dr. Peter C. Burns and Prof. Dr. Tianbo Liu

A Spontaneous Structural Transition of {U24Pp12} Clusters Triggered by Alkali Counterion Replacement in Dilute Solution

It′s up to U: A unique structural transition process for two isomeric uranyl peroxide clusters of Li/Na-{U24Pp12} and Na/K-{U24Pp12} triggered by counterion replacement is reported. The ITC and IR measurements of the two isomers revealed that the K+/Rb+ will be specifically coordinated onto the polyhedral windows before they can replace the loosely associated counterions.

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Hapten Synthesis

Development of Tetramethylenedisulfotetramine (TETS) Hapten Library: Synthesis, Electrophysiological Studies, and Immune Response in Rabbits.

Dr. Bogdan Barnych, Dr. Natalia Vasylieva, Tom Joseph, Susan Hulsizer, Dr. Hai M. Nguyen, Dr. Tomas Cajka, Prof. Isaac Pessah, Prof. Heike Wulff, Shirley J. Gee and Prof. Bruce D. Hammock

Development of Tetramethylenedisulfotetramine (TETS) Hapten Library: Synthesis, Electrophysiological Studies, and Immune Response in Rabbits.

Mimicking neurotoxic TETS: TETS and newly synthesized polycyclic sulfamides were shown to have similar GABAA receptor channel blocking properties and were both recognized by antibodies raised against synthetic TETS haptens.

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Anticancer Agents

Tumor Targeting with an isoDGR–Drug Conjugate

Simone Zanella, Simona Angerani, Arianna Pina, Paula López Rivas, Dr. Clelia Giannini, Dr. Silvia Panzeri, Dr. Daniela Arosio, Dr. Michele Caruso, Dr. Fabio Gasparri, Dr. Ivan Fraietta, Dr. Clara Albanese, Dr. Aurelio Marsiglio, Dr. Luca Pignataro, Prof. Dr. Laura Belvisi, Prof. Dr. Umberto Piarulli and Prof. Dr. Cesare Gennari

Tumor Targeting with an isoDGR–Drug Conjugate

Hitting bullseye: The skillful marksman (isoDGR–drug conjugate) targets cancer cells expressing integrin αVβ3, and releases the warhead (paclitaxel) selectively into them.

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Heteroacenes

Heterotetracenes: Flexible Synthesis and in Silico Assessment of the Hole-Transport Properties

Dr. Yifan Li, Dr. Ganna Gryn'ova, Felipe Saenz, Xavier Jeanbourquin, Prof. Kevin Sivula, Prof. Clémence Corminboeuf and Prof. Jérôme Waser

Heterotetracenes: Flexible Synthesis and in Silico Assessment of the Hole-Transport Properties

Acenes, acenes everywhere: Thienoacenes and furoacenes are among the most frequent molecular units found in organic materials. Here, we report a flexible and efficient synthesis of heterotetracenes based on a platinum- and gold-catalyzed cyclization–alkynylation domino process using ethynylbenziodoxole (EBX) hypervalent iodine reagents in the key step, as well the in silico estimation of the synthesized tetracenes’ charge mobility.

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NMR spectroscopy

Solid-State NMR Spectroscopy Proves the Presence of Penta-coordinated Sc Sites in MIL-100(Sc)

Raynald Giovine, Prof. Christophe Volkringer, Prof. Sharon E. Ashbrook, Dr. Julien Trébosc, Dr. David McKay, Dr. Thierry Loiseau, Prof. Jean-Paul Amoureux, Prof. Olivier Lafon and Dr. Frédérique Pourpoint

Solid-State NMR Spectroscopy Proves the Presence of Penta-coordinated Sc Sites in MIL-100(Sc)

MOF sites: Advanced solid-state NMR methods and first-principles calculations demonstrate for the first time the formation of penta-coordinated scandium sites. A 45Sc NMR experiment allows their specific observation in activated Sc3BTB2 and MIL-100(Sc) MOFs. The assignment of the ScO5 groups is supported by the DFT calculations of NMR parameters.

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Gas Sensors

A Designed ZnO@ZIF-8 Core–Shell Nanorod Film as a Gas Sensor with Excellent Selectivity for H2 over CO

Dr. Xiaonan Wu, Dr. Shunshun Xiong, Dr. Zhenghao Mao, Dr. Sheng Hu and Dr. Xinggui Long

A Designed ZnO@ZIF-8 Core–Shell Nanorod Film as a Gas Sensor with Excellent Selectivity for H2 over CO

Fabricating gas sensors: A ZnO@ZIF-8 core–shell nanorod film is fabricated through a solution deposition process. Fine-tuning the reaction conditions allows a ZnO@ZIF-8 core–shell structure with a thin, fine-grain, porous ZIF-8 shell to be obtained. The penetration of H2 through the ZIF-8 layer is easy because of the thin shell thickness, whereas passing of CO is hindered owing to the fine-grain confinement of the porous ZIF-8 shell (see figure). Selectivity for H2 over CO is realized using this ZnO@MOF complex.

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Materials Science

The Transformation of Hybrid Silica Nanoparticles from Solid to Hollow or Yolk-Shell Nanostructures

Xingwen Liu, Prof. Guangren Qian, Prof. Zheng Jiao, Prof. Minghong Wu and Prof. Haijiao Zhang

The Transformation of Hybrid Silica Nanoparticles from Solid to Hollow or Yolk-Shell Nanostructures

Mesoporous silica nanoparticles: A facile self-templating approach is presented for synthesis of hollow/yolk-shell mesoporous silica nanoparticles (HMSNs and YMSNs) through a facile selective etching of hybrid silica nanoparticles.

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Cluster Compounds

A Homochiral {CoΙΙ16CoΙΙΙ4} Supertetrahedral T4 Cluster from a Racemic Ligand with Ferromagnetic Behavior and High Photocatalytic Activity

Wei Du, Prof. Dr. Yue-Ling Bai, Xiuping Yin, Prof. Dr. Jianhui Fang, Prof. Dr. Shourong Zhu and Prof. Dr. Jun Tao

A Homochiral {CoΙΙ16CoΙΙΙ4} Supertetrahedral T4 Cluster from a Racemic Ligand with Ferromagnetic Behavior and High Photocatalytic Activity

Chiral cobalt cluster: An enantioselective coordination-induced mixed-valence homochiral Co20 supertetrahedral T4 cluster based on an inner CoIII4O4 cubane and four exterior CoII4O4 cubanes was synthesized from a racemic ligand, which displays ferromagnetic behavior and high photocatalytic activity.

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Organocatalysis

Phosphine-Mediated Sequential Annulation Reaction: Access to Functionalized Benzofurans and 4,5-Dihydrobenzofurans

Ling Liang, Xuelin Dong and Prof. Dr. You Huang

Phosphine-Mediated Sequential Annulation Reaction: Access to Functionalized Benzofurans and 4,5-Dihydrobenzofurans

Domino reaction: A new strategy for the facile access to multi-functionalized benzofurans and 4,5-dihydrobenzofurans is explored. The advantages include readily obtainable starting materials, mild and metal-free conditions, expedient and practical processes, excellent yields, and easy scale-up. The reaction demonstrates high efficiency to construct two rings in a single step.

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Supramolecular Chemistry

Supramolecular Amino Acid Based Hydrogels: Probing the Contribution of Additive Molecules using NMR Spectroscopy

Susana M. Ramalhete, Dr. Karol P. Nartowski, Nichola Sarathchandra, Jamie S. Foster, Dr. Andrew N. Round, Dr. Jesús Angulo, Dr. Gareth O. Lloyd and Prof. Yaroslav Z. Khimyak

Supramolecular Amino Acid Based Hydrogels: Probing the Contribution of Additive Molecules using NMR Spectroscopy

Unravelling hierarchical self-assembly: The heterogeneous nature of supramolecular hydrogels makes them challenging materials for structure characterisation. The combination of microscopy, rheology, diffraction and advanced NMR spectroscopy methods probe the variable length scales and dynamics present in these soft materials (see picture).

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Noncovalent Interactions

The Surprising Importance of Peptide Bond Contacts in Drug–Protein Interactions

Dr. Robert M. Parrish, Dr. Doree F. Sitkoff, Dr. Daniel L. Cheney and Prof. C. David Sherrill

The Surprising Importance of Peptide Bond Contacts in Drug–Protein Interactions

F-SAPT analysis is applied to elucidate the origins of binding enhancement in Cl- versus Me-containing ligands targeting the factor Xa S1-pocket. The enhancement of Cl-containing ligands is found to arise from many separate and intermediate-range contacts throughout the S1 pocket, notably including a number of significant differential electrostatic interactions with peptide bonds. This study underscores the potential of tools such as SAPT and F-SAPT to provide insights into molecular recognition that may not be wholly intuitive.

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Alkylzinc Oxygenation

Unprecedented Variety of Outcomes in the Oxygenation of Dinuclear Alkylzinc Derivatives of an N,N-Coupled Bis(β-diketimine)

Tomasz Pietrzak, Maciej Damian Korzyński, Dr. Iwona Justyniak, Dr. Karolina Zelga, Arkadiusz Kornowicz, Dr. Zbigniew Ochal and Prof. Janusz Lewiński

Unprecedented Variety of Outcomes in the Oxygenation of Dinuclear Alkylzinc Derivatives of an N,N-Coupled Bis(β-diketimine)

One to get them all! Harnessing dinuclear three-coordinate alkylzinc derivatives of N,N-coupled bis(β-diketimine) ligand (L) as a model system, we demonstrate for the first time that a slight modification of the reaction conditions might have a dramatic influence on the oxygenation reaction outcomes, leading to an unprecedented variety of products originating from a single reaction system, that is, partially and fully oxygenated zinc alkoxides, zinc alkylperoxides, and zinc hydroxide compounds (see scheme).

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Metal-Organic Frameworks

In Situ Formation of Co9S8/N-C Hollow Nanospheres by Pyrolysis and Sulfurization of ZIF-67 for High-Performance Lithium-Ion Batteries

Peiyuan Zeng, Jianwen Li, Ming Ye, Kaifeng Zhuo and Prof. Zhen Fang

In Situ Formation of Co9S8/N-C Hollow Nanospheres by Pyrolysis and Sulfurization of ZIF-67 for High-Performance Lithium-Ion Batteries

Better batteries: Co9S8/N-C hollow spheres were successfully synthesized through synchronous pyrolysis and sulfurization of ZIF-67 (see figure). These structures deliver a distinguished performance when applied as the anode in lithium-ion batteries.

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Imaging Agents

Simultaneous Triple Imaging with Two PARASHIFT Probes: Encoding Anatomical, pH and Temperature Information using Magnetic Resonance Shift Imaging

Katie-Louise N. A. Finney, Alice C. Harnden, Dr. Nicola J. Rogers, Dr. P. Kanthi Senanayake, Prof. Andrew M. Blamire, Dr. Dara O'Hogain and Prof. David Parker

Simultaneous Triple Imaging with Two PARASHIFT Probes: Encoding Anatomical, pH and Temperature Information using Magnetic Resonance Shift Imaging

The third degree: Triple imaging has been achieved (see figure), in vitro and in vivo, of the MR signal due to water and tert-butyl probe resonances of thulium and dysprosium complexes of a common ligand, permitting the simultaneous acquisition of pH and temperature of the region of interest.

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Ligand NMR Shifts

Insights into trans-Ligand and Spin-Orbit Effects on Electronic Structure and Ligand NMR Shifts in Transition-Metal Complexes

Anja H. Greif, Dr. Peter Hrobárik and Prof. Dr. Martin Kaupp

Insights into trans-Ligand and Spin-Orbit Effects on Electronic Structure and Ligand NMR Shifts in Transition-Metal Complexes

σ-Antibonding is the key! Surprisingly general trans ligand effects on NMR shifts in transition metal complexes are revealed by relativistic quantum-chemical analyses of ligand shifts, notably 1H shifts, in 5d10, 5d8, and 5d6 complexes. They are traced back to changes in σ-/π-spinor mixing by spin-orbit coupling due to a destabilization of a σ-type MO by strong trans ligands (see graphic). The insights allow qualitative and quantitative predictions of a wide range of ligand effects.

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Cyanides

Preparation and Characterization of Group 13 Cyanides

Prof. Ralf Haiges, Dr. Piyush Deokar, Dr. Monica Vasiliu, Trent H. Stein, Prof. Dr. David A. Dixon and Prof. Dr. Karl O. Christe

Preparation and Characterization of Group 13 Cyanides

The many ways of cyanide: Group 13 cyanides [(py)2Ga(CN)3], [(py)3In(CN)3], [(py)2Tl(CN)3], [(bipy)2Ga(CN)2][Ga(CN)4], [(bipy)In(CN)3], [(bipy)Tl(CN)3], [PPh4][Ga(CN)4], [PPh4]2[In(CN)5], and [PPh4]2[Tl(CN)5] were prepared in quantitative yields from the corresponding metal trifluorides through fluoride–cyanide exchange with Me3SiCN in the presence of pyridine (py), 2,2′-bipyridine (bipy), or [PPh4]CN.

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Metal-Organic Frameworks

Tunable Porous Coordination Polymers for the Capture, Recovery and Storage of Inhalation Anesthetics

Prof. Brendan F. Abrahams, A. David Dharma, Prof. Paul S. Donnelly, Dr. Timothy A. Hudson, Prof. Cameron J. Kepert, Prof. Richard Robson, Dr. Peter D. Southon and Keith F. White

Tunable Porous Coordination Polymers for the Capture, Recovery and Storage of Inhalation Anesthetics

3D Capture: The widespread use of a variety of inhalation anesthetics present significant environmental, health and economic challenges associated with their release into the atmosphere. The ability of a family of 3D framework materials containing square channels to capture and store a range of anesthetics is described.

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Materials Science

Synthesis, Structure, and Properties of Clathrate Si30.3(8)P15.7(8)Se7.930(3)

Prof. Hui Zhang, Prof. Wei Peng, Dr. Gang Mu, Dr. Tao Hu, Prof. Fuqiang Huang and Prof. Xiaoming Xie

Synthesis, Structure, and Properties of Clathrate Si30.3(8)P15.7(8)Se7.930(3)

Semiconducting materials: Si30.3(8)P15.7(8)Se7.930(3) and partial Te/Ge-substituted semiclathrates were synthesized and characterized (see figure). Theoretical calculations showed a semiconducting feature based on an ordered model of Si32P14Se7, and photoelectric response and diamagnetism were observed in Si30.3(8)P15.7(8)Se7.930(3).

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Alkylation

Cobalt-Catalyzed Alkylation of Secondary Alcohols with Primary Alcohols via Borrowing Hydrogen/Hydrogen Autotransfer

Frederik Freitag, Dr. Torsten Irrgang and Prof. Dr. Rhett Kempe

Cobalt-Catalyzed Alkylation of Secondary Alcohols with Primary Alcohols via Borrowing Hydrogen/Hydrogen Autotransfer

It is all about the al[Co]hol: The first cobalt catalyst for the alkylation of secondary alcohols with primary alcohols is reported. The system requires mild conditions with a high substrate scope, even for aliphatic motifs, and yields of the isolated products of up to 80 %.

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N2 Binding and Reduction

Feasibility of N2 Binding and Reduction to Ammonia on Fe-Deposited MoS2 2D Sheets: A DFT Study

Dr. Luis Miguel Azofra, Dr. Chenghua Sun, Prof. Dr. Luigi Cavallo and Prof. Dr. Douglas R. MacFarlane

Feasibility of N2 Binding and Reduction to Ammonia on Fe-Deposited MoS2 2D Sheets: A DFT Study

Bosch–Haber alternative? Mild conditions for N2 capture and catalytic conversion into NH3 is a key priority for “green fuels” technology. DFT findings show that Fe deposited on MoS2 2D sheets selectively captures N2 gas and converts N2 into NH3 with a maximum energy input of 1.02 eV, which arises from the activation barrier for the first H+/e pair transfer.

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Energetic Materials

N-Acetonitrile Functionalized Nitropyrazoles: Precursors to Insensitive Asymmetric N-Methylene-C Linked Azoles

Dr. Dheeraj Kumar, Dr. Gregory H. Imler, Dr. Damon A. Parrish and Prof. Dr. Jean'ne M. Shreeve

N-Acetonitrile Functionalized Nitropyrazoles: Precursors to Insensitive Asymmetric N-Methylene-C Linked Azoles

Fine-tuning of energetic properties: Properties of energetic compounds obtained through linking energetic pyrazoles to tetrazoles by means of N-methylene-C bridges can be fine-tuned. Initial studies show that this new approach is promising for synthesizing less sensitive energetic compounds with fine-tuned properties.

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Water Oxidation

Electrochemical Water Oxidation Catalyzed by an In Situ Generated α-Co(OH)2 Film on Zeolite-Y Surface

Dr. Suranjana Bose, Dr. Joyashish Debgupta, Rani M. Ramsundar and Prof. Samar K. Das

Electrochemical Water Oxidation Catalyzed by an In Situ Generated α-Co(OH)2 Film on Zeolite-Y Surface

Cobalt electrocatalysis: A simple but unique technique to in situ generate a thin-film of α-Co(OH)2 on the surface of zeolite-Y that acts as an efficient and stable catalyst for electrochemical water oxidation at alkaline pH is reported. A Tafel slope of 59 mV decade−1 in 0.1 m KOH (pH 13) suggests faster oxygen evolution kinetics (overpotential=329 mV; turnover frequency=0.35 molinline image  molCo−1 s−1 at 1 mA cm−2) than the existing α-Co(OH)2-based electrocatalysts operating in alkaline medium.

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Structure-Activity Relationships

Tunable GLUT–Hexose Binding and Transport via Modulation of Hexose C-3 Hydrogen-Bonding Capabilities

Dr. Venkata Pavan Kumar Kondapi, Dr. Olivier-Mohamad Soueidan, Prof. Christopher I. Cheeseman and Prof. Frederick G. West

Tunable GLUT–Hexose Binding and Transport via Modulation of Hexose C-3 Hydrogen-Bonding Capabilities

A series of fructose mimics with varying functionality at C-3 was prepared. Compounds with hydrogen bond donor groups at C-3 were recognized selectively by fructose transporter GLUT5, whereas those with hydrogen bond acceptor groups at C-3 were recognized by glucose transporter GLUT1.

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Oxidative Alkynylation

Highly Selective Olefin-Assisted PdII-Catalyzed Oxidative Alkynylation of Enallenes

Jeffrey L. Henry, Daniels Posevins, Bin Yang, Dr. Youai Qiu and Prof. Dr. Jan-E. Bäckvall

Highly Selective Olefin-Assisted PdII-Catalyzed Oxidative Alkynylation of Enallenes

Highly selective palladium-catalyzed oxidative alkynylation of enallenes has been developed, affording regio- and stereoselectively substituted trienynes. The reaction shows a broad substrate scope with good tolerance for various functional groups on the enallene and the terminal alkyne.

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Protein Folding

pH-Responsive Aminoproline-Containing Collagen Triple Helices

Jasmine Egli, Dr. Christiane Siebler, Dr. Boris Maryasin, Dr. Roman S. Erdmann, Cedric Bergande, Prof. Dr. Christian Ochsenfeld and Prof. Dr. Helma Wennemers

pH-Responsive Aminoproline-Containing Collagen Triple Helices

Position and stereochemistry matter: The position and the absolute configuration at C(4) of pH-responsive aminoproline residues can be used to tune the stability of collagen triple helices in acidic and basic environments (see scheme).

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Iron Complexes

Spin States of Homochiral and Heterochiral Isomers of [Fe(PyBox)2]2+ Derivatives

Kay E. Burrows, Sarah E. McGrath, Dr. Rafal Kulmaczewski, Dr. Oscar Cespedes, Simon A. Barrett and Prof. Malcolm A. Halcrow

Spin States of Homochiral and Heterochiral Isomers of [Fe(PyBox)2]2+ Derivatives

A heated switch: Homochiral [Fe((R)-LPh)2]2+ (green; LPh=2,6-bis{4-phenyloxazolinyl}pyridine) undergoes spin-crossover in CD3CN at 34 K lower temperature than its heterochiral diastereomer [Fe((R)-LPh)((S)-LPh)]2+ (red). This is attributed to a more twisted coordination geometry in the homochiral isomer, reflecting a steric clash between phenyl substituents. The equivalent diastereomers of [Fe(LiPr)2]2+ (LiPr=2,6-bis{4-isopropyloxazolinyl}pyridine) are both high-spin.

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Pincer Ligands

A Multifunctional Pincer Ligand Supports Unsaturated Cobalt: Five Functionalities in One Pincer

Dr. Alexander V. Polezhaev, Dr. Chun-Hsing Chen, Dr. Yaroslav Losovyj and Prof. Dr. Kenneth G. Caulton

A Multifunctional Pincer Ligand Supports Unsaturated Cobalt: Five Functionalities in One Pincer

Five in one: A pyridyl pincer ligand was designed to incorporate five different functionalities through PtBu2 and pyrazole pincer ligand arms (see figure). Ligand properties in neutral, monoanionic, and dianionic form were investigated in CoI and CoII complexes. The concept of a single-molecule frustrated Lewis pair (FLP) is discussed, and an alkali metal chloride was used as a model substrate to show FLP behavior.

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Chirality

Near-Infrared Circularly Polarized Light Triggered Enantioselective Photopolymerization by Using Upconversion Nanophosphors

Dr. Guang Yang, Dr. Liangfu Zhu, Dr. Jingang Hu, Dr. Hongyan Xia, Dr. Dong Qiu, Prof. Qijin Zhang, Prof. Douguo Zhang and Prof. Gang Zou

Near-Infrared Circularly Polarized Light Triggered Enantioselective Photopolymerization by Using Upconversion Nanophosphors

Transferring information: The inherent chirality of λ=980 nm circularly polarized light (CPL) could be transferred to upconversion luminescence (UCL) from lanthanide-doped upconversion nanoparticles (UCNPs), making it possible to realize near-IR CPL triggered enantioselective photopolymerization by incorporating UCNPs as antenna species (see figure). The screw direction of the formed helical polymer chains is the same as the handedness of the incident λ=980 nm CPL.

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Dyes/Pigments

10-Silacorroles Exhibiting Near-Infrared Absorption and Emission

Hiroto Omori, Prof. Dr. Satoru Hiroto and Prof. Dr. Hiroshi Shinokubo

10-Silacorroles Exhibiting Near-Infrared Absorption and Emission

Jump to 1000 nm! A new family of heteroporphyrinoid, 10-silacorroles, has been prepared through Pd-catalyzed silylation of a dibromodipyrrin NiII precursor. 10-Silacorroles exhibited near-infrared absorption (NIR) and emission. Theoretical analysis and electrochemical investigation revealed the presence of σ*–π* conjugation between the silicon atom and tetrapyrrolic macrocyclic skeleton.

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Fluorescent Probes

Accessing Structurally Diverse Near-Infrared Cyanine Dyes for Folate Receptor-Targeted Cancer Cell Staining

Dr. Sandra G. König and Prof. Dr. Roland Krämer

Accessing Structurally Diverse Near-Infrared Cyanine Dyes for Folate Receptor-Targeted Cancer Cell Staining

Tuneable wavelengths and selective cancer cell staining: A series of structurally diverse near-infrared (NIR) cyanine derivatives has been prepared using for example, Suzuki and Sonogashira cross-couplings. These derivatives cover a wavelength range of almost 100 nm. Selected modified cyanines were conjugated to folic acid for selective cancer cell targeting and were found to display a favourable combination of high fluorescence brightness and high affinity to folate receptor positive cancer cells.

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