通讯机构：
[Ernest Koranteng] L;Laboratory of Sustainable Polymers and Synthesis, Department of Chemistry Education, University of Education, Winneba, Ghana
摘要：
Abstract Developing green composites has received intense attention among the scientific community because of their ability to help alleviate the global environmental pollution challenges. This current work focused on preparing a bio‐based composite material with desirable performance using renewable materials like diatomaceous earth, and polylactic acid (PLA) with poly(butanediol adipate ester) prepolymer (PBAPU) as a compatibilizer. The composites were prepared by reactive mixing using an intensive mixer. Subsequently, the effects of the PBAPU content on the structure and properties of the composites were studied. From the test results, it was revealed that increasing the PBAPU content resulted in an increasing trend in the properties of the composites. For instance, the thermal stability of the composites was improved as the PBAPU content was increased, and the best thermal stability was obtained when 20 wt% PBAPU was added. In addition, the mechanical properties test results showed that the elongation at break and impact strength of the composites increased with increasing PBAPU content. On the contrary, the tensile strength of the composites decreased with increasing PBAPU content. The scanning electron microscope images showed that the compatibility between the PLA matrix and PBAPU in the composites was improved significantly. Based on the analysis of the test results for the material's structure, morphology, thermal stability, fluidity, and other properties, it can be concluded that a bio‐based composite material with desirable performance was successfully prepared.
通讯机构：
[Wu, DY ] X;Xiamen Univ, State Key Lab Phys Chem Solid Surface, Collaborat Innovat Ctr Chem Energy Mat, Xiamen 361005, Peoples R China.;Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, Xiamen 361005, Peoples R China.
摘要：
Stereoelectronic effects in single-molecule junctions have been widely utilized to achieve a molecular switch, but high-efficiency and reproducible switching remain challenging. Here, we demonstrate that there are three stable intramolecular conformations in the 9,10-diphenyl-9,10-methanoanthracen-11-one (DPMAO) systems due to steric effect. Interestingly, different electronic coupling approaches including weak coupling (through-space), decoupling, and strong coupling (through-bond) between two terminal benzene rings are accomplished in the three stable conformations, respectively. Theoretical calculations show that the molecular conductance of three stable conformations differs by more than 1 order of magnitude. Furthermore, the populations of the three stable conformations are highly dependent on the solvent effect and the external electric field. Therefore, an excellent molecular switch can be achieved using the DPMAO molecule junctions and external stimuli. Our findings reveal that modulating intramolecular electronic coupling approaches may be a useful manner to enable molecular switches with high switching ratios. This opens up a new route for building high-efficiency molecular switches in single-molecular junctions.
摘要：
Removing microcystins (MCs) safely and effectively has become an urgent global problem because of their extremely hazardous to the environment and public health. Microcystinases derived from indigenous microorganisms have received widespread attention due to their specific MC biodegradation function. However, linearized MCs are also very toxic and need to be removed from the water environment. How MlrC binds to linearized MCs and how it catalyzes the degradation process based on the actual three-dimensional structure have not been determined. In this study, the binding mode of MlrC with linearized MCs was explored using a combination of molecular docking and site-directed mutagenesis methods. A series of key substrate binding residues, including E70, W59, F67, F96, S392 and so on, were identified. Sodium dodecane sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to analyze samples of these variants. The activity of MlrC variants were measured using high performance liquid chromatography (HPLC). We used fluorescence spectroscopy experiments to research the relationship between MlrC enzyme (E), zinc ion (M), and substrate (S). The results showed that MlrC enzyme, zinc ion and substrate formed E-M-S intermediates during the catalytic process. The substrate-binding cavity was made up of N and C-terminal domains and the substrate-binding site mainly included N41, E70, D341, S392, Q468, S485, R492, W59, F67, and F96. The E70 residue involved in both substrate catalysis and substrate binding. In conclusion, a possible catalytic mechanism of the MlrC enzyme was further proposed based on the experimental results and a literature survey. These findings provided new insights into the molecular mechanisms of the MlrC enzyme to degrade linearized MCs, and laid a theoretical foundation for further biodegradation studies of MCs.
期刊：
Journal of Thermoplastic Composite Materials,2023年36(11):4349 - 4364 ISSN：0892-7057
通讯作者：
Qiangxian Wu
作者机构：
[Wu, Qiangxian; Zhang, Peirui; Jian, Kui] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan, Peoples R China.;[Weng, Fangqing] Hubei Univ Educ, Coll Chem & Life Sci, Wuhan, Peoples R China.;[Zhuang, Kejia; Hong, Liu; Gao, Shanjun; Zhao, Weiwei] Wuhan Univ Technol, Sch Mat Sci & Engn, Wuhan, Peoples R China.;[Wu, Qiangxian] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, Luoyu Rd 152, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Qiangxian Wu] K;Key Laboratory of Pesticide and Chemical Biology of the Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
关键词：
shell;polycaprolactone;composite;CaCO3
摘要：
Agricultural waste shells are another source of calcium carbonate (CaCO3). Waste shells contain natural polymers such as polysaccharides and protein which can react with active groups in a polymer by melt mixing to form a compatible layer in a composite material. The formation of a compatible layer helps to improve the compatibility and material toughness of a composite. At the same time, the presence of CaCO3 in waste shells can also help to improve the hardness of a material. Therefore, this work mainly focused on the preparation of composite materials using different kinds of shell powder, and also studied the effects of the interface structure between shell powder and polycaprolactone (PCL) and properties of the composite materials. In particular, this work, studied the effects of the crystal forms of various shell powder as well as the content of polysaccharide and protein on the tensile performance and thermal properties of composite materials. The results implied that the tensile performance of the composites prepared from different kinds of shell powder were slightly different. The composite prepared from shell powder containing aragonite-structured CaCO3 had a better elastic modulus than the composite prepared from shell powder containing calcite-structured CaCO3. Likewise, the composite material prepared from scallop shell powder had the best toughness and thermal properties. This work has laid a foundation for exploring the effects of all sorts of shell powder on the structure and properties of composite material.
摘要：
Catalytic oxidation technology is currently considered as a feasible approach to degrade and mineralize volatile organic compounds (VOCs). However, it is still challenging to realize efficient removal of VOCs through catalytic oxidation at room temperature. In our study, a novel flow-through electrocatalytic reactor was designed, composed of porous solid-electrolyte, gas-permeable titanium sub-oxides/titanium-foam (TiSO/Ti-foam) as anode and platinum coated titanium foam (Pt/Ti-foam) as cathode. This device could oxidize nearly 100% of benzene (10 ppm) to carbon dioxide at a current density of 1.2 mA/cm2 under room temperature. More importantly, the device maintained excellent stability over 1000 h. Mechanism of benzene mineralization was discussed. Hydroxyl radicals generated on the TiSO/Ti-foam anode played a crucial role in the oxidation of benzene. This study provides a promising prototype of the electrochemical air purifier, and may find its application in domestic and industrial air pollution control.
摘要：
The comprehensive understanding of contaminant interfacial behavior strongly depends on the in situ characterization technique, which is still a great challenge. In this study, we constructed a device integrated with open-circuit potentialand attenuated total reflectance Fourier transform infrared (OCP-ATR-FTIR) spectroscopy to simultaneously monitor the electrochemical and infrared spectral information on the interfacial reaction for the process analysis, taking the competitive adsorption of hexavalent chromium (Cr(VI)) and oxalate on hematite nanocubes (HNC) as an example. The synchronous OCP and infrared results revealed that Cr(VI) interacted with HNC via bidentate binuclear inner-sphere coordination, accompanied by electron transfer from HNC to Cr(VI), while oxalate was adsorbed on HNC through bidentate mononuclear side-on inner-sphere coordination with electron transfer from HNC to oxalate, and also outer-sphere coordination with negative charge accumulation. When oxalate was added to HNC with preadsorbed Cr(VI), oxalate would occupy the inner-sphere adsorption sites and thus cause the detaching of preadsorbed Cr(VI) from HNC. This study provides a promising in situ characterization technique for real-time interfacial reaction monitoring and also sheds light on the competitive adsorption mechanism of oxalate and Cr(VI) on the mineral surface.
摘要：
Alcoholic liver disease (ALD) has attracted widespread attention because of the ever-increasing alcohol consumption and high morbidity. However, there is still no effective detection method to prevent the deterioration of the disease. Cholesterol, as the main component of the cell membrane (CM), often transported to lipid droplets (LDs) for storage in hepatocytes. Meanwhile, abnormal changes of cholesterol could cause liver diseases, such as Tangier disease. Based on cholesterol could serve as a hub that affects the cell membrane fluidity (CMF) and the number of LDs, we planned to study the microscopic changes of CMF and LDs in ALD. As viscous media could limit the intramolecular motion of fluorescent probes, aggregation induced emission luminogens (AIEgens), which typically have rotators and vibrators in their structures and emit strongly in the aggregate state, may be promising candidates for CMF and LD study. So two AIE probes (TPCN and NDPB) were designed and synthesized based on the typical AIE skeleton, tetraphenylethylene (TPE), which could selectively target CMs and LDs, respectively. These probes exhibited high chemical stability, controllable emission, and excellent subcellular specificity. They successfully sensed the correlated changes of CMs and LDs in ALD model, which would contribute to understanding the microscopic process of ALD pathogenesis and further development of ALD therapeutic drugs.
摘要：
An amphiphilic AIE photosensitizer has been successfully developed, which allows for easily inserting into the bacterial membranes. Binding experiments with phospholipid preliminary demonstrates its membrane specificity. As expected, it is proved to possess a broad-spectrum bacterial staining performance and photodynamic antibacterial activity toward S. aureus and E. coli.
作者机构：
[Qin, Ying; Zhu, Chengzhou; Liu, Mingwang; Li, Jinli; Tan, Rong; Gu, Wenling; Wang, Hengjia] Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol, Key Lab Pesticide & Chem Biol,Minist Educ, Wuhan 430079, Peoples R China.;[Hu, Liuyong] Wuhan Inst Technol, Hubei Engn Technol Res Ctr Optoelect & New Energy, Hubei Key Lab Plasma Chem & Adv Mat, Wuhan 430205, Peoples R China.;[Li, Jinli] Jingchu Univ Technol, Sch Elect & Informat Engn, Jingmen 448000, Peoples R China.
通讯机构：
[Liuyong Hu] H;[Wenling Gu; Chengzhou Zhu] K;Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, Hubei Engineering Technology Research Center of Optoelectronic and New Energy Materials, Wuhan Institute of Technology, Wuhan 430205, PR China<&wdkj&>Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, PR China
作者机构：
[Bao, Guang-Ming; Wang, Yongze; Luo, Xin; Li, Shentian] Hubei Univ Technol, Hubei Prov Cooperat Innovat Ctr Ind Fermentat, Natl Ctr Cellular Regulat & Mol 111, Hubei Res Ctr Food Fermentat Engn,Key Lab Fermenta, Wuhan 430068, Hubei, Peoples R China.;[Xu, Weiqing; Luo, Zhen; Fang, Qie; Zhu, Chengzhou; Gu, Wenling; Wang, Hengjia] Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;[Zhu, CZ] Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
通讯机构：
[Zhu, CZ ] ;Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
摘要：
Circularly polarized luminescence (CPL) materials have attracted considerable attention for their promising applications in encryption, chiral sensing, and three-dimensional (3D) displays. However, the preparation of high-efficiency, pure blue CPL materials remains challenging. In this study, we reported an enantiomeric pair of triangle copper(I) clusters (R/S-Cu(3)) rigidified by employing chiral N-heterocyclic carbene (NHC) ligands with two pyridine-functionalized wingtips. These chiral clusters emitted pure blue phosphorescence that overlapped with that of the commercial blue phosphor having Commission Internationale de l'Eclairage (CIE) chromaticity coordinates of (0.14, 0.10), and the films exhibited an unprecedented photoluminescence quantum yield (PLQY) of ∼70.0%. Additionally, the solutions showed very bright circularly polarized phosphorescence (CPP) with a dissymmetry factor of ±2.1 × 10(-3). The excellent solubility and photostability endowed these pure-blue-emitting chiral clusters with promising applications as pure blue CPP inks for 3D printing white objects, such as precise-atomic-enlarged models of metal clusters and a lovely white stereoscopic "rabbit". The intricate mechanism underlying blue phosphorescence in this small cluster and across various states is elucidated through a comprehensive approach that integrates thorough analysis of luminescence properties, controlled experiments, and theoretical calculations. For the first time, we propose that the dominant high-energy emission center is constituted by delocalized hybrid orbitals over multiple atomic centers, encompassing both the metal and the coordinated atoms. This challenges stereotypical assumptions that the cluster center solely supports low-energy emissions. This work expands the currently limited range of CPP functional materials and provides a new direction for CPP applications involving NHC-stabilized metal clusters.
作者机构：
[Fu, Lijie; Liu, Fanglei; Zhao, Jiayi; Yang, Guohai; Qu, Lulu; Gu, Yingqiu] Jiangsu Normal Univ, Sch Chem & Mat Sci, Xuzhou 221116, Peoples R China.;[Zhu, Chengzhou] Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;[Zhu, Jun-Jie] Nanjing Univ, Sch Chem & Chem Engn, State Key Lab Analyt Chem Life Sci, Nanjing 210093, Peoples R China.;[Lin, Yuehe] Washington State Univ, Sch Mech & Mat Engn, Pullman, WA 99164 USA.
通讯机构：
[Lulu Qu] S;[Chengzhou Zhu] N;School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, PR China<&wdkj&>National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, P.R. China
摘要：
As recently developed two-dimensional (2D) materials, MXenes have attracted great attention in the fields of sensing, catalysis, energy, and electromagnetism due to their good electrical, mechanical, and optical properties and their biocompatibility. Their rich elemental composition, diverse surface functional groups and flexible bandgaps enable them to exhibit ideal physicochemical properties that are superior to those of traditional 2D materials. Therefore, MXenes not only serve as ideal biosensing materials but also show great potential in biomedical-related applications. In this review, we summarize the latest research on MXenes in the fields of biosensing and biomedicine. First, we introduce the different synthe-sis strategies and unique properties of MXenes. Then, according to the sensing mechanism, we divide the biosensing applications of MXenes into three subcategories: electrochemical, photochemical, and opto-electrochemical biosensors. Moreover, we systematically evaluate the biomedical applications of MXenes from four aspects: antibacterial activity, bioimaging, therapeutics and theranostics. How the specific chemical and physical properties of MXenes that can influence the efficiency of biosensing and biomedicine are highlighted, as well as the structure-performance relationships determining detection sensitivity and the toxicity of materials. Finally, we discuss the recent challenges and future prospects and opportunities for MXenes. It is expected that the review could promote the development of related fields.(c) 2022 Elsevier B.V. All rights reserved.
摘要：
Enrichment of OVs on oxide semiconductors is an effective strategy to promote their photocatalytic performances but limited by the maximum concentration allowed by lattice thermodynamics. Herein, we report that an In(I) doping strategy, realized by an UV light-induced reduction of a sluggish In(III) precursor, can promote OVs-laden BiOCl by up to 6.5 times for the visible-light sodium pentachlorophenate (PCPNa) degradation. The photocatalysis mechanism study highlighted the In(I) site as an electron transfer site could reduce PCPNa directly, related to the In(I) induced more negative conduction band and faster transfer of electron. Moreover, several monocyclic aromatic organic compounds (AOC) exhibited degradation selectivity over In(I) doped OVs-laden BiOCl (BOVs-In) by an electron reduction path, PCPNa with the lowest negative charge density on the benzene ring has been degraded fastest. Differently, the doped In(I) in BOVs-In mainly triggered the multiring Rhodamine B degradation by promoting the O-center dot(2)- generation not the directly electron reduction path. The electron transfer ability, band structure, and the free energy of O-2 activation over BOVs-In were confirmed by TPV spectra, EPR spectra and DFT calculation. This study illustrates an In(I) doping strategy to couple with OVs engineering for champion photoactivity of BiOCl for AOC degradation under visible light irradiation.
作者：
Gao, Yang-Yang;Yang, Wei-Cheng;Ashby Jr, Charles R.;Hao, Ge-Fei
期刊：
Drug Resistance Updates,2023年67:100934 ISSN：1368-7646
通讯作者：
Charles R. Ashby
作者机构：
[Yang, Wei-Cheng; Gao, Yang-Yang; Hao, Ge-Fei] Guizhou Univ, Ctr Res & Dev Fine Chem, Natl Key Lab Green Pesticide, Key Lab Green Pesticide & Agr Bioengn,Minist Educ, Guiyang 550025, Peoples R China.;[Hao, Ge-Fei] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan 430079, Peoples R China.;[Ashby Jr, Charles R.] St Johns Univ, Dept Pharmaceut Sci, New York, NY 10003 USA.
通讯机构：
[Charles R. Ashby] D;Department of Pharmaceutical Sciences, St. John’s University, New York, NY, USA
关键词：
Drug resistance;Cryptic binding sites;Resistance management
摘要：
The emergence of drug resistance is a primary obstacle for successful chemotherapy. Drugs that target cryptic binding sites (CBSs) represent a novel strategy for overcoming drug resistance. In this short communication, we explain and discuss how the discovery of CBSs and their inhibitors can overcome drug resistance.
摘要：
Pd/SSZ-13 has been proposed as a passive NOx adsorber (PNA) to effectively alleviate NOx emission during vehicle cold start. However, the chemical poisons which are derived from biodiesel and lubricant oil are challenging for the practical application of PNA technology. In this paper, Pd/SSZ-13 was poisoned by alkali/alkaline earth metals to investigate the effects of chemical poisons on the adsorption performance of Pd/SSZ-13. It was found that the alkali/alkaline earth metals led to the decrease of surface area and Brønsted acid sites of Pd/SSZ-13. Strikingly, the 27Al MAS NMR demonstrated that the alkali/alkaline earth metals could effectively prevent Pd/SSZ-13 from dealumination during hydrothermal aging treatment. The H2-TPR results showed that more than 70% of Pd2+ ions were lost in the Na- and K-impregnated Pd/SSZ-13, while almost complete loss of Pd2+ ions was observed in the Mg- and Ca-impregnated Pd/SSZ-13, which resulted in the deactivation of Pd/SSZ-13. Further, the DRIFTS results showed that Mg2+ and Ca2+ ions exhibited preferential substitution for Pd2+ ions, while Na+ and K+ ions preferentially replaced the H+ ions. This work provides insights into the effects of alkali/alkaline earth metals on Pd/SSZ-13, expecting to attract attention to design PNA materials with resistance to chemical poisons.
期刊：
Journal of Materials Science,2023年58(31):12764-12774 ISSN：0022-2461
通讯作者：
Cao, Y;Chen, DD
作者机构：
[Cao, Y; Asibaike, Laizaiti; Mukerabigwi, Jean Felix; Wu, Xuelin; Cao, Yu; Qu, Jiaying; Sun, Yuyang; Huang, Xueying] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan 430079, Peoples R China.;[Chen, Didi; Qu, Jiaying] Hubei Univ Educ, Hubei Key Lab Purificat & Applicat Plant Anticanc, Wuhan 430205, Peoples R China.;[Mukerabigwi, Jean Felix] Univ Rwanda, Coll Sci & Technol, Dept Chem, POB 3900, Kigali, Rwanda.
通讯机构：
[Cao, Y ] C;[Chen, DD ] H;Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan 430079, Peoples R China.;Hubei Univ Educ, Hubei Key Lab Purificat & Applicat Plant Anticanc, Wuhan 430205, Peoples R China.
摘要：
Due to its small particle size, high specific surface area, functional capability and long-term stable fluorescence, nanodiamond (ND) has been widely used in biomedical applications including fluorescent probes, drug delivery and biological imaging. Nevertheless, the metabolism of ND and its derivatives is not yet well understood for diverse biomedical applications. In this study, to evaluate the cytotoxicity and biodistribution of the ND derivative, pure ND was functionalized with ethylenediamine (EDA) as a linker (ND-EDA) and then covalently labeled with an organic fluorescent dye called calcein. The modified ND is referred to as ND-EDA-calcein. Even at the maximum dose of 0.1 mg & BULL;mL(-1), the in vitro results for ND-EDA-calcein against HepG2 and LO2 cell lines showed negligible cytotoxicity, which was in line with the in vivo observations. In addition, it was found that following an intraperitoneal injection, ND-EDA-calcein could be accumulated mostly in the liver and kidney of the mice but not in the spleen. It is interesting to note that after 5 days following intraperitoneal injection, mice can totally metabolize the elimination of ND-EDA-calcein outside of their bodies. Therefore, our findings suggested that NDs can be considered for various nanomedicine applications including drug delivery and biomarkers.
作者：
Song, Yongjun;Yu, Renyou;Meng, Xianwen;He, Lei
期刊：
Dyes and Pigments,2023年208:110876 ISSN：0143-7208
通讯作者：
He, Lei(helei@ccnu.edu.cn)
作者机构：
[Song, Yongjun; Meng, Xianwen; He, Lei; Yu, Renyou] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ,Hubei Int Sci & Technol Cooperat Base, Wuhan 430079, Peoples R China.;[He, Lei] South China Univ Technol, State Key Lab Luminescent Mat & Devices, Guangzhou 510640, Peoples R China.
通讯机构：
[Lei He] K;Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan, 430079, PR China<&wdkj&>State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, PR China
作者机构：
[Cheng, Ying; Xiao, Wen-Jing; Chen, Jia-Rong; Shi, De-Qing; Li, Tian-Tian; Chen, JR] Cent China Normal Univ, Coll Chem, Engn Res Ctr Photoenergy Utilizat Pollut Control &, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.;[Xiao, Wen-Jing] Shanghai Inst Organ Chem, State Key Lab Organometall Chem, 345 Lingling Rd, Shanghai 200032, Peoples R China.
通讯机构：
[Shi, DQ; Chen, JR ] C;Cent China Normal Univ, Coll Chem, Engn Res Ctr Photoenergy Utilizat Pollut Control &, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.
摘要：
Radical Cross‐CouplingA copper‐catalyzed enantioselective three‐component radical relay 1,2‐alkylesterification of 1,3‐dienes using cycloalkyl hydroperoxides and carboxylic acids was reported. This protocol features broad substrate scope and good functional group tolerance with respect to each component, providing practical access to a variety of distally keto‐functionalized chiral allylic esters with high enantioselectivity under mild and redox‐neutral conditions. Abstract Transition‐metal‐catalyzed radical relay cross‐coupling reactions of 1,3‐dienes have recently emerged as one of the most powerful methods for construction of structurally diverse allylic compound in a single chemical step. However, there still has been limited success in expanding substrate scope of radical precursors and coupling partners, as well as exploring catalytic asymmetric variants. Herein, we report a copper‐catalyzed enantioselective three‐component 1,2‐alkylesterification of 1,3‐dienes using cycloalkyl hydroperoxides as the carbonyl‐containing alkyl radical sources and carboxylic acids as O‐nucleophiles under mild and redox‐neutral conditions. This protocol features broad substrate scope and good functional group tolerance with respect to each component, providing practical access to a variety of distally keto‐functionalized allylic esters with high enantioselectivity. Mechanistic studies suggest the involvement of a sequential radical relay and C−O cross‐coupling in this three‐component radical reaction.
期刊：
JOURNAL OF ORGANIC CHEMISTRY,2023年88(11):7463-7468 ISSN：0022-3263
通讯作者：
Ke Gao
作者机构：
[Gao, Ke; Sun, Yulin] Cent China Normal Univ, CCNU uOttawa Joint Res Ctr, Key Lab Pesticide & Chem Biol, Minist Educ,Coll Chem, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Ke Gao] C;CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, P. R. China
摘要：
An inexpensive and efficient aminoguanidine-catalyzed reductive cyclization of o-phenylenediamines with CO2 in the presence of triethoxysilane is described. Various functionalized benzimidazoles, benzoxazole, and benzothiazole were synthesized in high yields. Mechanistic studies indicate that formic acid as a cocatalyst promotes the cyclization reaction.
