ChemistryEurope最新文献_第5页

Switching Product Selectivity in Immobilized Tungstate Catalysts by Control of Hydrophobicity of Mesoporous Silicate Supports 通过控制介孔硅酸盐载体的疏水性改变固定化钨酸盐催化剂的产品选择性

ChemistryEurope Pub Date : 2024-01-10 DOI: 10.1002/ceur.202300080

Ko Kuwamoto, Dr. Masaya Okamura, Prof. Dr. Shiro Hikichi

{"title":"Switching Product Selectivity in Immobilized Tungstate Catalysts by Control of Hydrophobicity of Mesoporous Silicate Supports","authors":"Ko Kuwamoto, Dr. Masaya Okamura, Prof. Dr. Shiro Hikichi","doi":"10.1002/ceur.202300080","DOIUrl":"10.1002/ceur.202300080","url":null,"abstract":"Novel mesoporous silicates modified with imidazolium cation were applied as the support for peroxotungstate. Stepwise introduction of multiple functional groups to SBA-15 was achieved by the combination of the direct and post-synthesis procedures. The co-condensation of tetraethoxysilane and 3-(imidazolyl-1-yl)-propyltriethoxysilane in the presence of the micelles of an amphiphilic surfactant yields the hydrophilic SBA-15 type silicate support with the imidazole modifier locating into the mesopores. The hydrophobic environment of the supports was imparted by capping the residual silanols on the silicate surface with trimethylsilyl groups. The fluoroalkyl- or alkyl-imidazolium cation-anchored supports were derived from the corresponding imidazole-functionalized precursors. The anion-exchanging reaction between peroxytungstate and the imidazolium cation-anchored supports yielded the corresponding tungstate-immobilized catalysts. The hydrophilic catalyst with the fluoroalkyl-imidazolium mediated alkene epoxidation with H2O2 in less polar solvents. The hydrophobic one, in contrast, produced diol through the epoxidation and following hydration in an aqueous solvent by the action of the highly Lewis acidic tungsten. The hydrophobic catalysts had the advantage of being more tolerant than hydrophilic catalysts, as evidenced by reusability tests. The activities of the alkyl-imidazolium catalysts were lower than those of the corresponding fluoroalkyl-imidazolium catalysts, indicating that the local structures surrounding the tungstate site affected the catalytic performance.","PeriodicalId":100234,"journal":{"name":"ChemistryEurope","volume":"2 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ceur.202300080","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139440152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Molecular Actuation of a Bistable Liquid-Crystalline [c2]Daisy Chain Rotaxane 双稳态液晶[c2]雏菊链旋烷的分子致动器

ChemistryEurope Pub Date : 2023-12-22 DOI: 10.1002/ceur.202300069

Dr. Christian C. Carmona-Vargas, Dr. Lara Faour, Dr. Shoichi Tokunaga, Dr. Doru Constantin, Guillaume Fleith, Dr. Emilie Moulin, Prof. Dr. Nicolas Giuseppone

引用次数: 0

6-Aryl-Substituted Harmanium Derivatives as Light-Up Probes for Fluorimetric DNA Detection and Staining of Eukaryotic Cells 作为荧光 DNA 检测和真核细胞染色的发光探针的 6-芳基取代的烃衍生物

ChemistryEurope Pub Date : 2023-12-20 DOI: 10.1002/ceur.202300045

Philipp Groß, Renée S. Hoffmann, Dr. Mareike Müller, Prof. Dr. Holger Schönherr, Prof. Dr. Heiko Ihmels

{"title":"6-Aryl-Substituted Harmanium Derivatives as Light-Up Probes for Fluorimetric DNA Detection and Staining of Eukaryotic Cells","authors":"Philipp Groß, Renée S. Hoffmann, Dr. Mareike Müller, Prof. Dr. Holger Schönherr, Prof. Dr. Heiko Ihmels","doi":"10.1002/ceur.202300045","DOIUrl":"10.1002/ceur.202300045","url":null,"abstract":"Nine 6-aryl-substituted harmanium derivatives were synthesized by Suzuki-Miyaura coupling of 6-bromoharmane with arylboronic acids and subsequent N2-benzylation. Depending on the substitution pattern of the aryl group the emission maxima cover a range between λfl=445 and 529 nm with quantum yields of Φfl=<0.01–0.92. The interactions with duplex DNA were investigated by photometric and fluorimetric titrations as well as CD and LD spectroscopy. These ligands bind to DNA by intercalation with binding constants of Kb=1–3×104 M−1. It was demonstrated by fluorescence microscopy that the 2-benzyl-6-(3-methoxyphenyl)harmanium derivative operates as a fluorescent light-up probe in the complex biological environment of eukaryotic cells, namely in NIH 3T3 mouse fibroblasts, as it stains the perinuclear cytoplasm and distinct substructures of the nucleus preferentially as compared with the rest of the nucleoplasm.","PeriodicalId":100234,"journal":{"name":"ChemistryEurope","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ceur.202300045","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139170927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Peroxo-Zr/Hf-Containing Wells-Dawson Polyoxometalates for H2O2-based Homogeneous, Heterogeneous, and Biphasic Oxidation Catalysis 用于基于 H2O2 的均相、异相和双相氧化催化的含过氧 Zr/Hf Wells-Dawson 聚氧化金属酸盐

ChemistryEurope Pub Date : 2023-12-20 DOI: 10.1002/ceur.202300066

Dr. Anusree Sundar, Dr. Nataliya V. Maksimchuk, Dr. Irina D. Ivanchikova, Dr. Olga V. Zalomaeva, Dr. Danica Bajuk-Bogdanović, Prof. Oxana A. Kholdeeva, Prof. Gordana Ćirić-Marjanović, Dr. Bassem S. Bassil, Prof. Ulrich Kortz

{"title":"Peroxo-Zr/Hf-Containing Wells-Dawson Polyoxometalates for H2O2-based Homogeneous, Heterogeneous, and Biphasic Oxidation Catalysis","authors":"Dr. Anusree Sundar, Dr. Nataliya V. Maksimchuk, Dr. Irina D. Ivanchikova, Dr. Olga V. Zalomaeva, Dr. Danica Bajuk-Bogdanović, Prof. Oxana A. Kholdeeva, Prof. Gordana Ćirić-Marjanović, Dr. Bassem S. Bassil, Prof. Ulrich Kortz","doi":"10.1002/ceur.202300066","DOIUrl":"10.1002/ceur.202300066","url":null,"abstract":"Four peroxo-Zr and Hf containing polyanions, [M2(O2)2(X2W17O61)2]16− (X=P, M=ZrIV (ZrP), HfIV (HfP); X=As, M=ZrIV (ZrAs), HfIV (HfAs) were synthesized and structurally characterized. The structures consist of two monolacunary Wells-Dawson ions which are connected head-on via two side-on peroxo bridges. The four new polyanions are solution-stable as shown by 31P NMR, Raman and FT-IR spectroscopic studies. Comparative studies on alcohol oxidation with a solvent- and phase-transfer catalyst-free biphasic oxidative system with homogeneous and supported-catalyst were performed and several noteworthy observations in reactivity and selectivity were observed, such as the highly selective ring-opening oxidation of cyclohexanol to adipic acid. Tetra-n-butylammonium salts of ZrP and HfP were also synthesized to study the catalytic activity of the compounds in the homogenous H2O2-based oxidation of olefins, α,β-unsaturated carbonyl compounds, and thioethers in organic solvent.","PeriodicalId":100234,"journal":{"name":"ChemistryEurope","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ceur.202300066","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138957955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Understanding the Retro-Cope Elimination Reaction of Linear Alkynes 了解线性炔烃的逆冲消除反应

ChemistryEurope Pub Date : 2023-12-14 DOI: 10.1002/ceur.202300072

Steven E. Beutick, Dr. Song Yu, Prof. Dr. Laura Orian, Prof. Dr. F. Matthias Bickelhaupt, Dr. Trevor A. Hamlin

{"title":"Understanding the Retro-Cope Elimination Reaction of Linear Alkynes","authors":"Steven E. Beutick, Dr. Song Yu, Prof. Dr. Laura Orian, Prof. Dr. F. Matthias Bickelhaupt, Dr. Trevor A. Hamlin","doi":"10.1002/ceur.202300072","DOIUrl":"10.1002/ceur.202300072","url":null,"abstract":"The bioorthogonal retro-Cope elimination reaction of linear alkynes R3C−C≡C−X (R3 = combinations of H, MeO, F; X = H, F, Cl, Br, I) with N,N-dimethylhydroxylamine was quantum chemically investigated using relativistic density functional theory at ZORA-BP86/TZ2P. This novel reaction can be tuned through judicious substitution of the alkyne at both the terminal and propargylic position to render second-order kinetics that rival and out-compete strain-promoted variants. Activation strain and quantitative molecular orbital analyses reveal that, both upon terminal or propargylic substitution of propyne, the main effect of substituting H for X is a lowering of the propyne LUMO which stabilizes the HOMO–LUMO interactions and thus the transition state. In the case of terminal substitution with larger halogens (X = Cl, Br, I), a secondary effect interferes: steric repulsion with these larger halogens is absorbed into a longer forming C⋯N bond leading to a more asynchronous reaction accompanied by less (not more) steric Pauli repulsion.","PeriodicalId":100234,"journal":{"name":"ChemistryEurope","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ceur.202300072","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139002384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Radical-Formation Management: Towards Aza-Analogues of the Benzothioxanthene Imide 自由基形成管理：开发苯并噻吨酰亚胺的氮杂类似物

ChemistryEurope Pub Date : 2023-11-27 DOI: 10.1002/ceur.202300071

Darío Puchán Sánchez, Dr. Pierre Josse, Dr. Monika G. Mutovska, Benjamin Siegler, Dr. Magali Allain, Korentin Morice, Dr. Philippe Blanchard, Prof. Frédéric Gohier, Prof. Tangui Le Bahers, Prof. Cyrille Monnereau, Prof. Yulian Zagranyarski, Prof. Dominik Lungerich, Prof. Dr. Clément Cabanetos

{"title":"Radical-Formation Management: Towards Aza-Analogues of the Benzothioxanthene Imide","authors":"Darío Puchán Sánchez, Dr. Pierre Josse, Dr. Monika G. Mutovska, Benjamin Siegler, Dr. Magali Allain, Korentin Morice, Dr. Philippe Blanchard, Prof. Frédéric Gohier, Prof. Tangui Le Bahers, Prof. Cyrille Monnereau, Prof. Yulian Zagranyarski, Prof. Dominik Lungerich, Prof. Dr. Clément Cabanetos","doi":"10.1002/ceur.202300071","DOIUrl":"10.1002/ceur.202300071","url":null,"abstract":"While benzothioxanthene imide (BTI) has shown promise in organic electronics and more recently in photodynamic therapy, its full potential remains yet undiscovered. In this context, this study repots the synthesis and characterization of aza derivatives in which the characteristic sulfur atom is replaced by an amino group. Adapted from the synthetic route of the BTI, a way was found to control the electronic structure of the radical intermediates, by means of a simple chemical modification. As a result, either the thermodynamically six-membered or the kinetically favored five-membered ring regioisomers can selectively be accessed. Photophysical rationalization of their structure-property relationships confirmed the richness, versatility and tunability of this class of rylene imide-based dyes.","PeriodicalId":100234,"journal":{"name":"ChemistryEurope","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ceur.202300071","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139230531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Front Cover: Synthesis and Enzymatic Conversion of Amino Acids Equipped with the Silanetriol Functionality: A Prelude to Silicon Biodiversification (ChemistryEurope 3/2023) 封面:具有硅三醇功能的氨基酸的合成和酶转化:硅生物多样化的前奏(化学欧洲3/2023)

ChemistryEurope Pub Date : 2023-11-15 DOI: 10.1002/ceur.202300076

Dr. Jade Dussart-Gautheret, Dr. Julie Rivollier, Dr. Cédric Simon, Dr. Alessandro De Simone, Dr. Jérôme Berthet, Prof. Stéphanie Delbaere, Régina Maruchenko, Claire Troufflard, Dr. Denis Lesage, Dr. Yves Gimbert, Dr. Gilles Lemière, Dr. Philippe Marlière, Prof. Louis Fensterbank

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Cover Feature: Pore Nanoarchitectonics of Carbon Nitrides for the Excited-State Deactivation of Confined Methylene Blue (ChemistryEurope 3/2023) 封面专题:用于受限亚甲基蓝激发态失活的碳氮化物的孔隙纳米结构(ChemistryEurope 3/2023)

ChemistryEurope Pub Date : 2023-11-15 DOI: 10.1002/ceur.202300075

Dr. Chunyu Li, Dr. Erik Troschke, Dr. Carolin Müller, Anindita Dasgupta, Prof. Dr. Christian Eggeling, Prof. Dr. Martin Oschatz, Prof. Dr. Benjamin Dietzek-Ivanšić

引用次数: 0

Sequence Information Transfer in Oligoarylacetylenes 低聚芳基乙炔中的序列信息传递

ChemistryEurope Pub Date : 2023-11-09 DOI: 10.1002/ceur.202300073

Dr. Kyle R. Strom, Dr. Jack W. Szostak

引用次数: 0

Non-Innocent π Linkers Affect Cooperativity in Hydrogen-Bonded Macrocycles 非无辜π连接体影响氢键大环的合作性

ChemistryEurope Pub Date : 2023-11-06 DOI: 10.1002/ceur.202300036

David Almacellas, Dr. Stephanie C. C. van der Lubbe, Alice A. Grosch, Iris Tsagri, Dr. Pascal Vermeeren, Dr. Jordi Poater, Prof. Dr. Célia Fonseca Guerra

引用次数: 0