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Visible-light-driven thio-carboxylation of alkynes with CO_(2):facile synthesis of thiochromones

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Science China Chemistry 2023年第5期66卷 1457-1466页

作者： Meng Miao Lei Zhu Hong Zhao Lei Song Si-Shun Yan Li-Li Liao Jian-Heng Ye Yu Lan Da-Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Pharmacy Third Military Medical UniversityChongqing 400038China School of Chemistry and Chemical Engineering Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030China College of Chemistry and Institute of Green Catalysis Zhengzhou UniversityZhengzhou 450001China

Difunctionalizing carboxylation of alkynes with CO_(2)is a sustainable and important strategy to generate valuable acrylate derivatives from both readily available starting materials.Such protocols,however,always suffer from the use of excess metallic reagents and transition metal residue.Herein,we report the first thio-carboxylation of alkynes with thiophenols and CO_(2),which is a visible-light-driven and transition metal-free process.In contrast to previous carboxylations of alkynes via two-electron activation of CO_(2),mechanistic and computational investigations suggest that the single-electron activation of CO_(2)is involved in the thio-carboxylation,rendering uniqueβ-carboxylation.The following cyclizing acylation affords important thiochromones efficiently.Moreover,the one-pot method features mild reaction conditions(room temperature,1 atmosphere of CO_(2)),high chemo-and regio-selectivity,easy scalability and facile derivatization of products to bioactive compounds.

关键词： carbon dioxide visible light carboxylation thiochromones

Box-Behnken experimental design for optimizing process parameters in carbonate-promoted direct thiophene carboxylation reaction with carbon dioxide

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Chinese Journal of Chemical Engineering 2022年第10期50卷 222-234页

作者： Qingjun Zhang Youguang Ma Xigang Yuan Aiwu Zeng State Key Laboratory of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Chemical Engineering Research Center Collaborative Innovative Center of Chemical Science and Engineering(Tianjin)Tianjin 300350China

A feasible synthesis route is developed for achieving the direct carboxylation of thiophene and CO_(2) in a relatively mild solvent-free carboxylate-assisted carbonate(semi)molten state.The effects of reaction factors on the carboxylate yield are investigated in the preliminary screening experiments,and the phase behavior analysis of the reaction medium is detected through the thermal characterization analysis of insitu high temperature X-ray diffraction measurement(in-situ XRD).The application of response surface methodology(RSM)based on the Box-Behnken design(BBD)is conducted to investigate the effect of the reaction parameters,such as reaction temperatu re,carbonate proportion,CO_(2) pressure and thiophene amount,on the product yield.The regressed second-order polynomial model equation well correlates all the independent variables.The analysis of variance(ANOVA)results reveal that the quadratic effect of reaction temperature is the most effective parameter in this carboxylation reaction owing to it’s the highest contribution to the sum of square(30.18%).The optimum reaction conditions for maximum product yield are the reaction temperature of 287℃,carbonate proportion of 32.20%,CO_(2) pressure of 1.0MPa and thiophene amount of 9.35 mmol.Operating under these selected experimental conditions,a high product yield(50.98%)can be achieved.

关键词： carboxylation Solvent-free medium Molten salt Optimization Response surfacemethodology

Direct carboxylation of thiophene with CO_(2) in the solvent-free carboxylate-carbonate molten medium:Experimental and mechanistic insights

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Chinese Journal of Chemical Engineering 2022年第10期50卷 264-282页

作者： Qingjun Zhang Pengyuan Shi Xigang Yuan Youguang Ma Aiwu Zeng State Key Laboratory of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Chemical Engineering Research Center Collaborative Innovative Center of Chemical Science and Engineering(Tianjin)Tianjin 300350China

A feasible synthesis route is devised for realizing direct carboxylation of thiophene and CO_(2) in a relatively mild solvent-free carboxylate-assisted carbonate(semi)molten medium.The effects of reaction factors on product yield are investigated,and the phase behavior analysis of the reaction medium is detected through the thermal characterization techniques.Product yield varies with the alternative carboxylate co-salts,which is attributed to the difference in deprotonation capacity caused by the base effect within the system.Besides,the detailed mechanism of this carbonate-promoted carboxylation reaction is studied,including two consecutive steps of the formation of carbanion through breaking the C-H bond(s)via the carbonate and the nucleophile attacking the weak electrophile CO_(2) to form C-C bond(s).The activation energy barrier in C-H activation step is higher than the following CO_(2) insertion step whether for the formation of the mono-and/or di-carboxylate,which is in good agreement with that of kinetic isotope effect(KIE)experiments,indicating that the C-H deprotonation is slow and the forming presumed carbanion reacts rapidly with CO_(2).Both the activation energy barriers in deprotonation steps are the minimal for the cesium cluster system since there have the weak the cesium Cs-heteroatom S(thiophene)and Cs-the broken proton interactions compared to the K2CO3 system,which is likely to enhance the acidity of C-H bond,lowering the C-H activation barrier.Besides,these mechanistic insights are further assessed by investigating base and C-H substrate effects via replacing Cs2CO3 with K2CO3 and furoate(la)with thiophene monocarboxylate(1b)or benzoate(1c).

关键词： Inert CAH bond carboxylation Solvent-free medium Base effect Density functionaltheory(DFT)study

Recent advances in electrochemical carboxylation reactions using carbon dioxide

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Green Chemical Engineering 2022年第2期3卷 125-137页

作者： Xiao-Fei Liu Ke Zhang Li Tao Xiao-Bing Lu Wen-Zhen Zhang State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian116024China

From the viewpoint of abundance,economy,non-toxicity,and renewability,CO_(2) is the ideal C1 synthon in organic synthetic chemistry.Utilizing CO_(2) for chemical conversion to synthesize highly value-added fine chem-icals is of great significance.Organic electrochemical synthesis that employs electrons as redox reagents to achieve selective oxidation or reduction has attracted much attention in the past decades.In this review,recent advances in the electrochemical carboxylations using CO_(2) from the perspective of organic synthesis will be summarized.We give an overview about the research progress of electrocarboxylation reactions according to the classification of substrates,such as alkenes,organic(pseudo)halides,aldehydes,ketones,and imines.The carb-anions produced by cathodic reduction are important intermediates in the electrocarboxylation reactions using CO_(2).

关键词： Carbon dioxide Organic electrochemical synthesis carboxylation Green chemistry Carboxylic acid

Surface carboxylation of iron oxide nanoparticles brings reduced macrophage inflammatory response through inhibiting macrophage autophagy

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Regenerative Biomaterials 2022年第1期9卷 414-423页

作者： Di Deng Shengxiang Fu Zhongyuan Cai Xiaomin Fu Rongrong Jin Hua Ai National Engineering Research Center for Biomaterials Sichuan UniversityNo.29 Wangjiang RoadChengdu 610064China Department of Radiology West China HospitalSichuan UniversityChengdu 610041China

Macrophage autophagy is a common biological response triggered by nanomaterials,which is closely related to the regulation of inflammation.Superparamagnetic iron oxide(SPIO)nanoparticles have been used for study of autophagy response due to their broad biomedical applications.However,few reports have focused on how to regulate the macrophage autophagy response induced by SPIO nanoparticles.In this study,SPIO nanoparticles grafted with carboxyl groups were synthesized and for the comparison of macrophage autophagy with unmodified nanoparticles.The study on the correlation between autophagy and inflammation induced by the two kinds of SPIO nanoparticles was also included,and the one that grafted with carboxyl groups shows a reduction of autophagy and thereby caused a milder inflammatory response.We proposed that the increased amount of albumin adsorption on the surface of carboxylated SPIO nanoparticles,a protein previously proven to attenuate autophagy,can be considered an important reason for reducing autophagy and inflammation.In general,the carboxyl modification of SPIO nanoparticles has been demonstrated to reduce inflammation by inhibiting macrophage autophagy,which may provide some insights for the design of nanomaterials in the future.

关键词： autophagy inflammation superparamagnetic iron oxide carboxylation

Homogeneous Light-Driven Catalytic Direct carboxylation with CO2

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Chinese Journal of Chemistry 2018年第6期36卷 545-554页

作者： Fen Tan Guoyin Yin Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients Hubei University of Education Wuhan Hubei 430205 China The Institute for Advanced Studies Wuhan University Wuhan Hubei430072 China

Carbon dioxide is a ubiquitous and inexpensive one-carbon source for chemical synthesis, and the efficient incorporation of CO2 into organic molecules is of widespread research interest both for economic and ecological reasons. The methodologies to employ carbon dioxide as a single-carbon unit to construct molecules relevant for agrochemical and pharmaceutical research include many elegant approaches, including asymmetric transformations. Even though remarkable achievements have been made in the field of light-driven catalysis, especially photoredox catalysis, homogeneous light-driven catalytic carboxylation by employing CO2 as the key reagent has only become a subject of increasing attention in recent years. Therefore, this concise review will discuss the latest advances in this research area.

关键词： homogeneous catalysis photocatalysis green chemistry carboxylation carbon dioxide

Stereoselective electrochemical carboxylation ofα,β-unsaturated sulfones

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Chinese Chemical Letters 2023年第6期34卷 315-318页

作者： Zi-Xin Yang Liangchuan Lai Jingze Chen Hong Yan Ke-Yin Ye Fen-Er Chen Institute of Pharmaceutical Science and Technology College of ChemistryFuzhou UniversityFuzhou 350108China Department of Chemistry Engineering Center of Catalysis and Synthesis for Chiral MoleculesFudan UniversityShanghai 200433China Shanghai Engineering Research Center of Industrial Asymmetric Catalysis of Chiral Drugs Fudan UniversityShanghai 200433China

As an attractive C1 synthon,carbon dioxide(CO_(2))has been extensively used in organic synthesis to produce carboxylic acids.In this research,stereoselective electrochemical carboxylation ofα,β-unsaturated sulfones has been developed under transition-metal-free conditions.All the cinnamic acids and the derivatives are obtained selectively in the E-configuration.Besides,arylpropiolates also can be produced from alkynyl sulfones.

关键词： Electrosynthesis Carbon dioxide carboxylation α β-Unsaturated sulfone α β-Unsaturated carboxylic acid

carboxylation of Aromatics by CO<sub>2</sub>under “Si/Al Based Frustrated Lewis Pairs” Catalytic System

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Journal of Materials Science and Chemical Engineering 2015年第1期3卷 103-108页

作者： Miaofei Gu Zhenmin Cheng State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China

carboxylation of aromatics by CO2 to generate corresponding carboxylic acids is recently providing a novel approach to utilize the green gas CO2, in which the activation of CO2 is the key procedure. Among the many catalytic systems employed in the carboxylation, the concept of “Frustrated Lewis Pairs” (FLPs) was scarcely mentioned, which perform excellently in activating small molecules like CO2. The FLPs are combinations of Lewis acids and Lewis bases which failed to form adducts due to their bulky steric congestion. In this paper, we first attempted various Si/Al Based FLPs to catalyze the carboxylation of aromatics through the activation of CO2, and a good yield of 62% - 97% was obtained. The reaction mechanism was proposed, involving the activation of CO2 mainly contributed by AlCl3 in cooperation with organosilane, forming an intermediate consisting of CO2, AlCl3, and R4Si, as well as the subsequent electrophilic attack to aromatics, thus to promote the carboxylation reaction.

关键词： carboxylation Frustrated Lewis Pairs Carbon Dioxide Aromatic Catalytic System

Electrocarboxylation of CO_(2) with Organic Substrates:Toward Cathodic Reaction

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Transactions of Tianjin University 2023年第4期29卷 254-274页

作者： He Yao Mei-Yan Wang Chengguang Yue Bangman Feng Wenhao Ji Chunbo Qian Shengping Wang Sheng Zhang Xinbin Ma School of Chemical Engineering and Technology Key Laboratory for Green Chemical Technology of Ministry of EducationCollaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072China Ningbo Key Laboratory of Green Petrochemical Carbon Emission Reduction Technology and Equipment Zhejiang Institute of Tianjin UniversityNingbo 315200China

Electrocarboxylation of carbon dioxide(CO_(2))using organic substrates has emerged as a promising method for the sustainable synthesis of value-added carboxylic acids due to its renewable energy source and mild reaction conditions.The reactivity and product selectivity of electrocarboxylation are highly dependent on the cathodic behavior,involving a sequence of electron transfers and chemical reactions.Hence,it is necessary to understand the cathodic reaction mechanisms for optimizing reaction performance and product distribution.In this work,a review of recent advancements in the electrocarboxylation of CO_(2)with organic substrates based on different cathodic reaction pathways is presented to provide a reference for the development of novel methodologies of CO_(2)electrocarboxylation.Herein,cathodic reactions are particularly classified into two categories based on the initial electron carriers(i.e.,CO_(2)radical anion and substrate radical anion).Furthermore,three cathodic pathways(ENE(N),ENED,and EDEN)of substrate radical anion-induced electrocarboxylation are discussed,which differ in their electron transfer sequence,substrate dissociation,and nucleophilic reaction,to highlight their implications on reactivity and product selectivity.

关键词： Carbon dioxide Electrocatalysis carboxylation Cathodic reaction Carboxylic acids