Chemistry - A European Journal最新文献_第6页

Recent Advances in Pd-Catalyzed Directed meta-C–H Olefination: Strategies and Outlook 钯催化间碳氢定向烯烃研究进展：策略与展望。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-07-03 DOI: 10.1002/chem.71364

Hang-Cheng Li, Nai-Ting Wu, Ren-Lin Wang, Yi Hu, Hua-Jin Xu

{"title":"Recent Advances in Pd-Catalyzed Directed meta-C–H Olefination: Strategies and Outlook","authors":"Hang-Cheng Li, Nai-Ting Wu, Ren-Lin Wang, Yi Hu, Hua-Jin Xu","doi":"10.1002/chem.71364","DOIUrl":"10.1002/chem.71364","url":null,"abstract":"<div>\u0000 \u0000 Vinyl arenes are widely found in natural products, pharmaceuticals, and functional materials, and serve as important intermediates for the construction of complex molecular architectures. Among the various synthetic strategies available, transition-metal-catalyzed direct C–H olefination has emerged as a particularly concise and efficient alternative approach. Through the use of directing strategies and ligand modulation, both the regioselectivity and stereoselectivity of C–H bond cleavage can be precisely controlled. Among the available catalytic systems, palladium catalysts occupy a central position owing to their outstanding reactivity and broad applicability. In comparison, ortho-C–H functionalization has become relatively well established, whereas remote C–H functionalization remains underdeveloped due to the high-energy macrocyclic metallacyclic transition states involved, as well as factors such as conformational strain and steric hindrance. Current studies have primarily focused on directing-group design and substrate scope expansion, while other key issues have received comparatively limited attention. Building upon our group's research efforts in this area, this review systematically summarizes the recent advances, mechanistic insights, and applications of palladium-catalyzed directing-group-assisted meta-C–H olefination, with the aim of providing a useful reference for future developments in this field.\u0000 </div>","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":"32 38","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148381384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Symmetry Breaking in Achiral Porphyrins: Noncovalent Origins of Emergent Optical Activity 非手性卟啉的对称性破缺：涌现光学活性的非共价起源。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-07-06 DOI: 10.1002/chem.71367

Arunima Cheran, Betsy Marydasan, Jatish Kumar

引用次数: 0

Regioselective Aldol Reactions Directed by Charge and Orbital Effects in Cyclic Germyl Dienolates: Synthesis of Three Distinct Regio- and Stereoisomers 由电荷和轨道效应引导的环香叶二烯醇酯的区域选择性醛醇反应：三种不同区域和立体异构体的合成。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-07-17 DOI: 10.1002/chem.71422

Taishi Nojima, Akihito Konishi, Makoto Yasuda

{"title":"Regioselective Aldol Reactions Directed by Charge and Orbital Effects in Cyclic Germyl Dienolates: Synthesis of Three Distinct Regio- and Stereoisomers","authors":"Taishi Nojima, Akihito Konishi, Makoto Yasuda","doi":"10.1002/chem.71422","DOIUrl":"10.1002/chem.71422","url":null,"abstract":"Regioselective aldol reactions of dienolates represent a valuable method for the construction of complex molecular scaffolds; however, controlling the reaction site of the dienolate remains a significant challenge. This study presents a method for regioselectivity switching in the aldol reactions of cyclic Ge-dienolates, which are generated from the (4 + 1) cycloaddition of allenoates with Ge(II) salts. Through systematic tuning of the charge and orbital distributions of the Ge-dienolates and their aldehyde reaction partners, regio- and stereoselective access to three distinct aldol adducts (syn-α-, anti-α-, and anti-γ-adducts) is achieved. The aldol reaction of Ge-dienolates generally proceeds via an orbital-controlled pathway to afford the anti-γ-adduct through a cyclic transition state. Activation of the aldehyde with a Lewis acid shifts the reaction to a charge-controlled pathway, resulting in the syn-α-adduct via an acyclic transition state. Notably, coordination of a ligand or solvent to the Ge center of the cyclic Ge-dienolates increases electron density, thereby favoring a charge-controlled pathway, promoting selective α-addition to yield the anti-α-adduct through a distinct cyclic transition state. The synthetic utility of these types of adducts is further demonstrated via gold-catalyzed intramolecular C─H/C–Ge cross-coupling, which enables the efficient synthesis of various fused-ring systems.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":"32 38","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/chem.71422","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148467880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stepwise Synthesis of Tetrabenzotriazaporphyrins (TBTAPs) and Their Open 2- and 3-Ring Fragments. 四苯并三氮卟啉（TBTAPs）及其开放2环和3环片段的分步合成

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-07-06 DOI: 10.1002/chem.71357

Jacob Gretton, Ala Alturk, Sonia Remiro-Buenamañana, Alejandro Díaz-Moscoso, Amirah A Aldawsari, Maha S Albayaa, Isabelle Chambrier, David L Hughes, Simon J Coles, Graham J Tizzard, Andrew N Cammidge

{"title":"Stepwise Synthesis of Tetrabenzotriazaporphyrins (TBTAPs) and Their Open 2- and 3-Ring Fragments.","authors":"Jacob Gretton, Ala Alturk, Sonia Remiro-Buenamañana, Alejandro Díaz-Moscoso, Amirah A Aldawsari, Maha S Albayaa, Isabelle Chambrier, David L Hughes, Simon J Coles, Graham J Tizzard, Andrew N Cammidge","doi":"10.1002/chem.71357","DOIUrl":"10.1002/chem.71357","url":null,"abstract":"The intermediate structures between phthalocyanines and porphyrins (so-called hybrid structures) are intriguing materials that offer the potential to combine features of each parent, and also offer tunability of properties through modification and further functionalization. We report here the stepwise synthesis of tetrabenzotriazaporphyrins(TBTAPs) bearing different core and meso-aryl substituents. The results are unexpected; our previous results showed that the reaction between aminoisoindoline initiator (\"A\") and a phthalonitrile (\"B\") led preferentially to 2:2, ABBA hybrids, presumed to be via reaction between 2x \"AB\" intermediates. Here we report the synthesis of discrete \"AB\" fragments and their subsequent reaction chemistry. Reaction of the AB intermediates under typical macrocyclization conditions fails to produce more than a trace of the expected ABBA TBTAP hybrid. Rather, the reactions yield the 3:1 ABBB TBTAPs predominantly, alongside an open ABA trimer (a tripyrrin analogue). The protocol provides a useful alternative synthesis of TBTAPs that minimizes the formation of phthalocyanine side-product. ABA trimer synthesis was separately optimized to produce a short series. The materials show broad absorption across the visible range and assemble into a preferred helical, coiled arrangement as revealed by crystallography.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":" ","pages":"e71357"},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13660487/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148389521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Metal-Ion Regulated Light-Free Z→E Isomerization of Azobenzene Glycomacrocycle 金属离子调控偶氮苯糖环的无光Z→E异构化。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-06-25 DOI: 10.1002/chem.71333

Yang Zhou, Jinbiao Jiao, Mathieu Lordez, Jean-Yves Salpin, Juan Xie

{"title":"Metal-Ion Regulated Light-Free Z→E Isomerization of Azobenzene Glycomacrocycle","authors":"Yang Zhou, Jinbiao Jiao, Mathieu Lordez, Jean-Yves Salpin, Juan Xie","doi":"10.1002/chem.71333","DOIUrl":"10.1002/chem.71333","url":null,"abstract":"We reported a 26-membered azobenzene-embedded glycomacrocycle, that undergoes metal-ion-mediated, light-free Z→E isomerization across an unprecedented kinetic spanning from seconds (Cu2+) to weeks (Co2+). The macrocycle was synthesized via an intramolecular glycosylation strategy incorporating an azobenzene-triazole linker and an isopropylidene-protected pentaerythritol unit. Upon addition of divalent metal perchlorates (Cu2+, Ni2+, Co2+, Pb2+) to the Z-isomer, three distinct kinetic regimes were observed and characterized by absorption spectroscopy and electrospray ionization-mass spectrometry. Beyond simple coordination-driven isomerization, Cu2+, Ni2+, and Pb2+ were found to act as Lewis acids, promoting in situ hydrolysis of the isopropylidene acetal moiety. This metal-induced chemical remodeling dramatically simplifies the macrocycle's conformational landscape, from a fragmented multi-conformer ensemble to a singular global minimum, as validated by a conformational search method. A photokinetic experiment on the copper complex revealed near-instantaneous re-establishment of the E-complex upon UV cessation, representing the fastest light-free Z→E reversion observed in this system. Crucially, the macrocyclic framework is recoverable by metal scavenging with QuadraPure IDA, confirming the system's reversibility and recyclability. This work introduces a design principle wherein a glycomacrocyclic scaffold, photoresponsive azobenzene, metal-ion-mediated light-free isomerizable, and Lewis-acid-labile protecting group cooperatively generate a programmable, temporally tunable molecular switch with broad potential in stimuli-responsive materials and chemical logic applications.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":"32 38","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/chem.71333","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148325117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Polymerization-Induced Liquid Crystallinity With Broadened Mesophase Temperature Range in Side-Chain Polymers Incorporating Photoresponsive 4-Cyanoazobenzene Units 含有光响应性4-氰偶氮苯单元的侧链聚合物中扩大中间相温度范围的聚合诱导液晶性。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-06-25 DOI: 10.1002/chem.71326

Omkar Dash, Jyoti Swarup Thakur, Pradip Kumar Mondal, Susanta K. Nayak

{"title":"Polymerization-Induced Liquid Crystallinity With Broadened Mesophase Temperature Range in Side-Chain Polymers Incorporating Photoresponsive 4-Cyanoazobenzene Units","authors":"Omkar Dash, Jyoti Swarup Thakur, Pradip Kumar Mondal, Susanta K. Nayak","doi":"10.1002/chem.71326","DOIUrl":"10.1002/chem.71326","url":null,"abstract":"<div>\u0000 \u0000 A series of 4-cyanoazobenzene containing monomers and their corresponding side-chain polymers with different polymer backbones and alkoxy spacer lengths were analyzed to investigate the influence of polymer backbones on the thermotropic liquid crystalline behavior. The solid-state features of the monomers were elucidated by single crystal X-ray diffraction, revealing the presence of C─H···X (X = O/N/F), C─X···π (X = H/O) and π···π interactions. Hirshfeld surface and energy framework analysis further demonstrated that dispersion interactions are the dominant contributor to the overall crystal packing. Thermal analysis of the acrylate and 2-fluoroacrylate based monomer indicated the presence of nematic mesophase over a narrow temperature window (1°C–2°C), whereas the methacrylate-terminated monomers did not display liquid crystalline behavior. In contrast, polymerization resulted in a significantly broadened nematic mesophase range exceeding 70°C, highlighting the critical role of the polymer backbone in mesophase stabilization. Further, the monomers displayed photoinduced nematic-isotropic phase transition upon irradiation with 365 nm UV light. Additionally, the monomers and polymers exhibited reversible trans<math></math>cis isomerization in solution under 365 nm UV and 510 nm visible light irradiation, achieving up to 90% conversion efficiency. These findings underscore the role of the polymer backbone in promoting liquid crystallinity and photoresponse toward the development of stimuli-responsive materials.\u0000 </div>","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":"32 38","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148325193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Straightforward Synthesis of C2-Symmetric Ansaranes: Potential 3-D Structures to Mimic Naphthalene c2对称Ansaranes的直接合成：模拟萘的潜在三维结构。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-06-25 DOI: 10.1002/chem.71317

Lisenn Doré, Lauriane Avelino, Fabienne Fache, Olivier Piva

{"title":"Straightforward Synthesis of C2-Symmetric Ansaranes: Potential 3-D Structures to Mimic Naphthalene","authors":"Lisenn Doré, Lauriane Avelino, Fabienne Fache, Olivier Piva","doi":"10.1002/chem.71317","DOIUrl":"10.1002/chem.71317","url":null,"abstract":"<div>\u0000 \u0000 A library of compounds possessing a rare 3-D pentacyclic skeleton known as ansarane has been prepared in high yields and only 3 steps. The sequence required at first the oxidation of salicylic alcohol with sodium periodate to deliver a spiroepoxyhexadienone, which spontaneously underwent, even at low temperature, a dimerization through a [4+2] cycloaddition. The trimeric adduct obtained in 86% was next irradiated at 350 nm to quantitatively furnish an ansarane. The C2 symmetry of the molecule and the presence of two different electrophilic centers allowed a bidirectional approach through the regioselective ring-opening of the two epoxides by various nucleophiles (halogen, chalcogen, azido,…), or the olefination of the two keto groups. In parallel, the cyclic analogues of grandifloracin and grandifloridins, compounds reported for their biological properties against pancreatic cell lines, has been also prepared by a parent sequence. Finally, and on the basis of x-ray diffraction analysis, the 3D can be considered as a bioisostere of the naphthyl group.\u0000 </div>","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":"32 38","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148325200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Working Under Pressure: Empirical Findings on the Challenges Facing PhD Students in Chemistry 压力下的工作：化学博士生面临的挑战的实证研究。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-07-02 DOI: 10.1002/chem.71358

Alexandra Tietze, Anna Röhnelt, Laura Hillebrand, Sylvia Schlöglmann, Monja Schilling, Chris M. Wanner, Katrin Beuthert

{"title":"Working Under Pressure: Empirical Findings on the Challenges Facing PhD Students in Chemistry","authors":"Alexandra Tietze, Anna Röhnelt, Laura Hillebrand, Sylvia Schlöglmann, Monja Schilling, Chris M. Wanner, Katrin Beuthert","doi":"10.1002/chem.71358","DOIUrl":"10.1002/chem.71358","url":null,"abstract":"<div>\u0000 \u0000 This study examines well-being, supervision quality, work-related conflicts, workload, and financing among PhD students in chemistry, drawing on a nationwide survey in Germany (N = 722). The data reveals considerable challenges across all domains of the survey: 61% had considered discontinuing their PhD, citing mental health issues, poor supervision, and high workloads. Satisfaction with supervision correlated strongly with feedback quality, leadership, and communication skills (r = .72–.78, p <.001), highlighting the central role of supervisory practices in PhD students’ well-being. Over half reported working more than 45 h per week, and one-fifth could not cover living expenses with their income, pointing to structural mismatches between workload expectations and financial support. Reports of discrimination, power abuse, and inadequate career support further highlight systemic shortcomings in PhD training environments. These findings emphasize the need for structural reforms in PhD education and research environments to support well-being and sustain the future research workforce.\u0000 </div>","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":"32 38","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148366259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Deazapurine-Based Cyclic Selenenyl Sulfide as a Glutathione Peroxidase Mimetic. 以地氮嘌呤为基础的环硒酰硫代谷胱甘肽过氧化物酶模拟物。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-06-25 DOI: 10.1002/chem.71330

Adam Hałuszczuk, Aleksandra Liana, Andrzej S Skwarecki, Witold Przychodzeń

{"title":"Deazapurine-Based Cyclic Selenenyl Sulfide as a Glutathione Peroxidase Mimetic.","authors":"Adam Hałuszczuk, Aleksandra Liana, Andrzej S Skwarecki, Witold Przychodzeń","doi":"10.1002/chem.71330","DOIUrl":"10.1002/chem.71330","url":null,"abstract":"Glutathione peroxidase (GPx) is a vital antioxidant enzyme that protects cells from oxidative damage by catalyzing the reduction of reactive oxygen species (ROS). The development of efficient GPx mimetics is crucial for reproducing this protective function in therapeutic and industrial contexts. In this study, we describe the gram-scale synthesis of a water-soluble deazapurine-based cyclic selenenyl sulfide via an efficient five-step route. The catalytic activity of this compound was evaluated under physiologically relevant glutathione (GSH) concentrations (∼6.5 mM). Activity was quantified using a newly developed UPLC-based assay and benchmarked against results obtained with the classical NMR-based Iwaoka assay, ensuring cross-validation of kinetic parameters. Using these complementary approaches, we demonstrate that the selenenyl sulfide 6a catalyzes thiol oxidation with substantially higher efficiency than ebselen, a widely studied GPx mimic, under applied assay conditions. In addition, the compound exhibits exceptional chemical stability, with no NMR-detectable signs of degradation after two years of storage. These findings underscore the potential of cyclic selenenyl sulfides as GPx mimetics, providing a strong rationale for evaluating their catalytic properties in more complex chemical and biological contexts.","PeriodicalId":144,"journal":{"name":"Chemistry - A European Journal","volume":" ","pages":"e71330"},"PeriodicalIF":3.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148325137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Unified Approach for the Synthesis of Conformationally Locked and sp²-sp³ Fused Hybrids. 合成构象锁定和sp2-sp3融合杂化的统一方法。

IF 3.6 2区化学

Chemistry - A European Journal Pub Date : 2026-10-13 Epub Date: 2026-07-03 DOI: 10.1002/chem.71359

Ervis Saraci, Federica Plavi, Giovanni Viscardi, Chad N Ungarean, Massimo Boiocchi, Christophe Salome, Quentin Lefebvre, Thomas C Fessard, David Sarlah

引用次数: 0