On-Demand Chirality Transfer of Human Serum Albumin to Bis(thiophen-2-yl)hexafluorocyclopentenes through Their Photochromic Ring Closure

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The Journal of Organic Chemistry

The Journal of Organic Chemistry: Latest Articles (ACS Publications)
Authors: Yuri Saeki, Megumi Kayanuma, Aki Nitta, Yasuteru Shigeta, Izuru Kawamura, Tetsuya Nakagawa, Takashi Ubukata, and Yasushi Yokoyama
feedproxy.google.com/~r/acs/joceah/~3/wn4cHPR0pY4/acs.joc.1c00849

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Design of High-Performance Pyridine/Quinoline Hydrazone Photoswitches

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The Journal of Organic Chemistry

The Journal of Organic Chemistry: Latest Articles (ACS Publications)
Authors: Bernard Mravec, Šimon Budzák, Miroslav Medved’, Lukáš F. Pašteka, Chavdar Slavov, Torben Saßmannshausen, Josef Wachtveitl, Jozef Kožíšek, Lea Hegedüsová, Juraj Filo, and Marek Cigáň
feedproxy.google.com/~r/acs/joceah/~3/HNYcqwGcnPc/acs.joc.1c01174

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An Approach to Developing Cyanines with Simultaneous Intersystem Crossing Enhancement and Excited-State Lifetime Elongation for Photodynamic Antitumor Metastasis

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Journal of the American Chemical Society

Journal of the American Chemical Society: Latest Articles (ACS Publications)
Authors: Xueze Zhao, Qichao Yao, Saran Long, Weijie Chi, Yuxin Yang, Davin Tan, Xiaogang Liu, Haiqiao Huang, Wen Sun, Jianjun Du, Jiangli Fan, and Xiaojun Peng
feedproxy.google.com/~r/acs/jacsat/~3/n9HrNyL3yf0/jacs.1c06275

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Scalable Total Synthesis of (+)- and (−)-Codonopiloneolignanin A via Ti(IV)/NHC Cooperative Control Highly Enantioselective Dimerization of Multisubstituted Cinnamaldehyde

Organic Letters: Latest Articles (ACS Publications)
Authors: Xiangxin Li, Huaya Yong, Xiaohong Fan, Yajuan Zheng, Zhen Wang, and Zhixiang Xie
feedproxy.google.com/~r/acs/orlef7/~3/uNB4F1C-r4o/acs.orglett.1c02408

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Molecular Plasticity of Crystalline CK2α′ Leads to KN2, a Bivalent Inhibitor of Protein Kinase CK2 with Extraordinary Selectivity

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Journal of Medicinal Chemistry

Journal of Medicinal Chemistry: Latest Articles (ACS Publications)
Authors: Dirk Lindenblatt, Violetta Applegate, Anna Nickelsen, Merlin Klußmann, Ines Neundorf, Claudia Götz, Joachim Jose, and Karsten Niefind
feedproxy.google.com/~r/acs/jmcmar/~3/sd6_is-PJww/acs.jmedchem.1c00063

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Emerging Approaches to Overcome Acquired Drug Resistance Obstacles to Osimertinib in Non-Small-Cell Lung Cancer

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Journal of Medicinal Chemistry

Journal of Medicinal Chemistry: Latest Articles (ACS Publications)
Authors: Matin Shaikh, Yashodeep Shinde, Rahul Pawara, Malleshappa Noolvi, Sanjay Surana, Iqrar Ahmad, and Harun Patel
feedproxy.google.com/~r/acs/jmcmar/~3/VSLGrRe3xvo/acs.jmedchem.1c00876

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Rh(III)-Catalyzed Regioselective Annulations of 3-Arylisoxazolones and 3-Aryl-1,4,2-dioxazol-5-ones with Propargyl Alcohols: Access to 4-Arylisoquinolines and 4-Arylisoquinolones

Organic Letters: Latest Articles (ACS Publications)
Authors: Tong-Tong Wang, Hai-Shan Jin, Man-Man Cao, Ru-Bing Wang, and Li-Ming Zhao
feedproxy.google.com/~r/acs/orlef7/~3/zqW5jrvDCjo/acs.orglett.1c02049

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Multichromophore Molecular Design for Thermally Activated Delayed-Fluorescence Emitters with Near-Unity Photoluminescence Quantum Yields

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The Journal of Organic Chemistry

The Journal of Organic Chemistry: Latest Articles (ACS Publications)
Authors: Dongyang Chen, Yu Kusakabe, Yongxia Ren, Dianming Sun, Pachaiyappan Rajamalli, Yoshimasa Wada, Katsuaki Suzuki, Hironori Kaji, and Eli Zysman-Colman
feedproxy.google.com/~r/acs/joceah/~3/qoX9zoi80mM/acs.joc.1c01101

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Sustainable synthesis of [1]benzopyran azo dyes using CuCr2O4 NPs

Sustainable synthesis of [1]benzopyran azo dyes using CuCr2O4 NPs

Abstract

In this study, copper chromite nanoparticles (CuCr2O4 NPs) were prepared by a simple hydrothermal method. This nanomaterial was found as an efficient heterogeneous magnetic catalyst for the synthesis of a new class of [1]benzopyran azo dyes via pseudo-three-component reaction of (E)-1,2-diphenyl-1-diazene with 4-hydroxycoumarin in the ratio 1:2. The aim of the present work was to provide a practical and high yielding protocol that offers several advantages such as simple procedure with an easy work-up, mild reaction conditions, and the use of CuCr2O4 NPs as an efficient and easily recoverable catalyst.

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A Photo‐ and Redox‐Driven Two‐Directional Terthiazole‐Based Switch: A Combined Experimental and Computational Investigation

A Photo- and Redox-Driven Two-Directional Terthiazole-Based Switch: A Combined Experimental and Computational Investigation

Molecular switches are key elements for the design of stimuli-responsive systems and materials. Of particular interest are switches that can be fully operated both by light and electricity, the two most popular inputs. It is shown for the first time that a terarylene photoswitch can be effectively transformed to an efficient photo and redox one when decorated with the electroactive N-methyl pyridinium group. The driving forces behind different switching processes are revealed by a joint experimental and theoretical approach.

Abstract

Terthiazoles with redox-active substituents like an N-methyl pyridinium group and ferrocene have been synthesized and their photo- and electro-chromic behaviors were investigated. The presence of two lateral N-methyl pyridinium substituents in the structure of terthiazole proved to be effective in inducing not only the reductive ring-closure of the terthiazole core but also its oxidative ring-opening reaction, leading to the first terarylene-based switch able to fully operate both photochemically and electrochemically. Moreover, the large increase in the redox potential between its open and closed form (700 mV) means that a part of the photon energy necessary to trigger the cyclization is stored in the form of chemical potential available for other works. Introduction of a second redox-active unit such as ferrocene onto the central thiazolyl moiety is found to inhibit the photochromism of the switch but not its redox switchability, which, instead, got improved for the ring-opening reaction via the redox properties of the ferrocenyl unit. The optical and redox properties of the switch in its different oxidation states are analyzed with the aid of DFT calculations in order to rationalize different switching processes.

Wiley: Chemistry – A European Journal: Table of Contents
Authors: Nicolò Baggi, Anne Léaustic, Sihem Groni, Elodie Anxolabéhère‐Mallart, Régis Guillot, Rémi Métivier, François Maurel, Pei Yu
chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202101945

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Zeolitic Vanadotungstates with Ultrahigh Porosities for Separation of Butane and Isobutane

Zeolitic Vanadotungstates with Ultrahigh Porosities for Separation of Butane and Isobutane

Zeolitic octahedral metal oxides based on vanadotungstates with different cations were successfully obtained and characterized. They efficiently separated n-butane from n-butane and i-butane mixtures. Single-gas adsorption measurements showed that the adsorbed volume of n-butane was much larger than that of i-butane. Breakthrough measurements showed that the materials efficiently achieved the separation of n-butane and i-butane, which was environmental friendly and cost-efficiently.

Abstract

Zeolitic vanadotungstates with tunable microporosity have potential interests in gas separation. The pore openings of the materials are in between the diameters of normal butane and isobutane, which causes the materials only adsorb normal butane. The breakthrough experiments show that the materials effectively separate normal butane from the normal butane and isobutane mixture even at high temperatures. The robust materials can be reused without loss of the separation performance.

Wiley: Chemistry – A European Journal: Table of Contents
Authors: Panpan Hu, Qianqian Zhu, Zhenxin Zhang, Yanshuo Li, Wataru Ueda
chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202102148

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Metal‐Free Photoredox‐Catalyzed Hydrodefluorination of Fluoroarenes Utilizing Amide Solvent as Reductant

Metal-Free Photoredox-Catalyzed Hydrodefluorination of Fluoroarenes Utilizing Amide Solvent as Reductant

A metal-free photoredox-catalyzed hydrodefluorination of fluoroarenes was realized by using N,N,N’,N’-tetramethyl-para-phenylenediamine as a catalyst under UV light irradiation. This reaction does not necessitate aliphatic amine additives as sacrificial reductants. The mechanistic studies indicated that the amide solvent NMP plays a critical role as a hydrogen and electron donor for this photoredox catalysis.

Abstract

A metal-free photoredox-catalyzed hydrodefluorination of fluoroarenes was achieved by using N,N,N’,N’-tetramethyl-para-phenylenediamine (1) as a strong photoreduction catalyst. This reaction was applicable not only to electron-rich monofluoroarenes but also to polyfluoroarenes to afford non-fluorinated arenes. The experimental mechanistic studies indicated that the amide solvent NMP plays an important role for regeneration of the photocatalyst, enabling additive-free photoreduction catalysis.

Wiley: Chemistry – A European Journal: Table of Contents
Authors: Naoyuki Toriumi, Kazuya Yamashita, Nobuharu Iwasawa
chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202101813

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Expedient Synthesis of Bridged Bicyclic Nitrogen Scaffolds via Orthogonal Tandem Catalysis

Expedient Synthesis of Bridged Bicyclic Nitrogen Scaffolds via Orthogonal Tandem Catalysis

Escape from flatland: Increased saturation (fraction of sp3) is more likely to be successful when moving compounds through the drug development pipeline. Bridged nitrogen heterocycles have a huge potential in drug discovery, although long synthetic sequences are typically required. New step-economic and selective organic synthesis is therefore highly sought after. Bert U. W. Maes et al. describe in their Research Article (DOI: 10.1002/anie.202106716) the synthesis of the normorphan skeleton through challenging tandem catalysis. Cover design by Joris Snaet.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Sovan Biswas, Ben F. Van Steijvoort, Marjo Waeterschoot, Narendraprasad Reddy Bheemireddy, Gwilherm Evano, Bert U. W. Maes
onlinelibrary.wiley.com/doi/10.1002/anie.202109132

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Nanoscale Advancement Continues—From Catalysts and Reagents to Restructuring of Reaction Media

Nanoscale Advancement Continues—From Catalysts and Reagents to Restructuring of Reaction Media

In the highlighted article, the effect of alkane and water additives on the structure of several ionic liquids was used to increase the acidity of liquid reaction media and to accelerate the acid-catalyzed transformations. A possible connection between the appearance of a pronounced microstructure of the obtained systems and their performance in catalytic processes was proposed on the basis of microscopy and spectroscopy measurements.

Abstract

Comprehensive studies dedicated to the search for specific properties of matter at the micro- and nanoscales have greatly enriched the fields of chemistry and materials science. From the point of view of synthetic chemistry, discoveries in the field of nanoscale catalysis, in which the size effects of active centers are used to accelerate the reactions, are of particular importance. However, another approach for the promotion of chemical transformations based on the micro- or nanoconfinement of reacting molecules or even on the structuring of the reaction media as a whole is gaining interest as a highly valuable tool. Herein, we highlight the example of an increase in the efficiency of phenol alkylation and tert-butylation of benzyl alcohol in reaction media based on ionic liquids by the creation of acidic microdomains in the presence of small molecule additives.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Alexey S. Kashin, Valentine P. Ananikov
onlinelibrary.wiley.com/doi/10.1002/anie.202107075

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Probing the Paradigm of Promiscuity for N‐Heterocyclic Carbene Complexes and their Protein Adduct Formation

Probing the Paradigm of Promiscuity for N-Heterocyclic Carbene Complexes and their Protein Adduct Formation

Isostructural N-heterocyclic carbene Ru, Os, Rh, and Ir complexes showed distinctive reactivity to hen egg white lysozyme by forming adducts at different binding sites and/or underwent different ligand exchange reactions. Protein crystallography, mass spectrometry and computational studies demonstrated the role of the metal centers and the protein microenvironment in determining their selectivity for a specific site.

Abstract

Metal complexes can be considered a “paradigm of promiscuity” when it comes to their interactions with proteins. They often form adducts with a variety of donor atoms in an unselective manner. We have characterized the adducts formed between a series of isostructural N-heterocyclic carbene (NHC) complexes with Ru, Os, Rh, and Ir centers and the model protein hen egg white lysozyme by X-ray crystallography and mass spectrometry. Distinctive behavior for the metal compounds was observed with the more labile Ru and Rh complexes targeting mainly a surface l-histidine moiety through cleavage of p-cymene or NHC co-ligands, respectively. In contrast, the more inert Os and Ir derivatives were detected abundantly in an electronegative binding pocket after undergoing ligand exchange of a chlorido ligand for an amino acid side chain. Computational studies supported the binding profiles and hinted at the role of the protein microenvironment for metal complexes eliciting selectivity for specific binding sites on the protein.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Matthew P. Sullivan, Monika Cziferszky, Iogann Tolbatov, Dianna Truong, Davide Mercadante, Nazzareno Re, Ronald Gust, David C. Goldstone, Christian G. Hartinger
onlinelibrary.wiley.com/doi/10.1002/anie.202106906

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Light‐Harvesting Supramolecular Phosphors: Highly Efficient Room Temperature Phosphorescence in Solution and Hydrogels

Light-Harvesting Supramolecular Phosphors: Highly Efficient Room Temperature Phosphorescence in Solution and Hydrogels

One of the highest quantum yield ambient solution state (ca. 41.8 %) and hydrogel (ca. 34 %) room temperature phosphorescence, by employing an organic–inorganic supramolecular scaffolding strategy is reported. These soft-hybrids are further employed as an efficient light-harvesting scaffold by co-anchoring acceptor dyes to yield triplet-to-singlet energy transfer mediated delayed fluorescence.

Abstract

Solution phase room-temperature phosphorescence (RTP) from organic phosphors is seldom realized. Herein we report one of the highest quantum yield solution state RTP (ca. 41.8 %) in water, from a structurally simple phthalimide phosphor, by employing an organic–inorganic supramolecular scaffolding strategy. We further use these supramolecular hybrid phosphors as a light-harvesting scaffold to achieve delayed fluorescence from orthogonally anchored Sulforhodamine acceptor dyes via an efficient triplet to singlet Förster resonance energy transfer (TS-FRET), which is rarely achieved in solution. Electrostatic cross-linking of the inorganic scaffold at higher concentrations further facilitates the formation of self-standing hydrogels with efficient RTP and energy-transfer mediated long-lived fluorescence.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Swadhin Garain, Bidhan Chandra Garain, Muthusamy Eswaramoorthy, Swapan K. Pati, Subi J. George
onlinelibrary.wiley.com/doi/10.1002/anie.202107295

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