90th Anniversary of Acta Chimica Sinica Default Latest Most Read Please wait a minute... Review Recent Advances and Application Prospects in Photothermal Materials★ He Xu, Pengbo Han, Anjun Qin, Ben Zhong Tang Acta Chimica Sinica 2023, 81 (10): 1420-1437. DOI: 10.6023/A23050232 Abstract (900) HTML (84) PDF (13311KB)(934) Knowledge map Photothermal effect refers to the characteristics of materials that could generate heat under the irradiation of sun or laser light. It can not only maximize the efficiency of solar energy conversion, but also break through the spatiotemporal limitation of laser light transmission, which holds excellent potential and application prospect. Currently, researchers have developed many photothermal materials based on three main photothermal effect mechanisms, plasmonic heating, non-radiative relaxation in semiconductors and thermal vibration in molecules, which include metal nanomaterials, inorganic semiconductor materials, carbon materials, two-dimensional transition metal carbides and nitrides (MXenes), organic small molecules, polymer materials, metal organic framework (MOF), covalent organic framework (COF), organic co-crystals materials, etc. Among them, inorganic materials have the advantages of a wide range of sources, simple structure and excellent thermal stability, while organic materials can be easily designed in structure, and have better biocompatibility. Based on these attractive characteristics, the photothermal effects have been extensively investigated in the area of energy utilization, biomedicine, catalytic conversion, intelligent devices, etc., and realized the applications in photothermal solar evaporation, photothermal therapy, photothermal catalysis, photothermal functional materials. In addition to the rapid development of traditional applications, novel applications have also been explored, such as anti-icing coating, reversible adhesive, agriculture heaters, photothermal energy storage, photothermal induced self-healing materials, photothermal-driven soft robots, etc. However, there are still some challenges in the research of photothermal materials, such as narrow absorption range, low photothermal conversion efficiency, limited application development, and difficulty in use of the elevated temperature induced by photothermal effect. This review briefly summarizes the progresses in the development, utilization of photothermal materials. The challenges and the development direction of photothermal materials are also discussed. It is hope that this review could provide inspiration for the further research in terms of construction of new photothermal materials and innovation of their application. Fig. & Tab. | Reference | Related Articles | Metrics Perspective Research Progress of Porphyrin-Based Covalent Organic Frameworks in Photocatalysis★ Minghui He, Ziqiu Ye, Guiqing Lin, Sheng Yin, Xinyi Huang, Xu Zhou, Ying Yin, Bo Gui, Cheng Wang Acta Chimica Sinica 2023, 81 (7): 784-792. DOI: 10.6023/A23040178 Published: 07 June 2023 Abstract (879) HTML (61) PDF (3233KB)(1265) Knowledge map Covalent organic frameworks (COFs) are a class of crystalline organic porous materials formed by molecular building blocks via covalent bonds. According to the dimensions of the framework extended in space, COFs can be divided into two-dimensional and three-dimensional COFs. Owing to their high specific surface area, good stability and strong designability, COFs have broad prospects in the fields of gas adsorption and separation, catalysis, sensing, optoelectronics, and energy storage. In the field of photocatalysis, COFs have the following advantages. First, COFs are highly designable, which can achieve efficient photocatalysis by introducing different functional units to adjust the band gap energy and light absorption range. Secondly, the ordered structure of COFs improves the electron-hole separation efficiency. In addition, the high specific surface area and abundant active sites of COFs can promote the photocatalytic reaction and improve the reaction rate. Finally, COFs are connected by covalent bonds, which make them highly stable and facilitate the maintenance of catalytic activity in the photocatalytic process. Porphyrins are a class of 18 π-electron conjugated macrocyclic compounds formed by the interconnection of four pyrroles, which can be involved in photosynthesis as the core part of chlorophyll and other biomolecules. As a kind of functional units with large π-conjugated structure and good photophysical properties, porphyrins usually have strong absorption in the 400~450 nm (Soret band) and 500~700 nm (Q band) regions, and their photocatalytic properties can be regulated by coordination with metal ions and modification of functional groups, which has unique advantages in the field of photocatalysis. By introducing porphyrins into COFs, combined with their unique advantages, porphyrin-based COFs have been found great potential in the field of photocatalysis due to the exceptional optical absorption in a broad spectral range, multiple active sites and effective electron-hole separation ability. As a new type of photocatalyst, porphyrin-based COFs have attracted much interest and have been rapidly developed in the field of photocatalysis. In this review, we focus on the discussion of porphyrin-based COFs in the photocatalytic CO2 reduction, photocatalytic water splitting, photocatalytic organic transformation, and photocatalytic reduction of hexavalent uranium. Finally, the prospects and challenges of porphyrin-based COFs in photocatalysis are discussed. Fig. & Tab. | Reference | Related Articles | Metrics Review Recent Research Progress and Prospect of Photothermal Materials in Seawater Desalination★ Di Yang, Xiaofan Shi, Jijie Zhang, Xian-He Bu Acta Chimica Sinica 2023, 81 (8): 1052-1063. DOI: 10.6023/A23040148 Published: 25 June 2023 Abstract (874) HTML (73) PDF (2579KB)(966) Knowledge map Solar water evaporation system has appealing advantages of low cost and high energy efficiency, which is of great significance to alleviate energy crisis, reduce water pollution and promote seawater desalination. However, the natural mechanism of solar-driven water evaporation system is often affected via low evaporation rate and small absorption spectrum range. The interface evaporation strategy that locally heats and limits heat loss is widely recognized as a high-performance and sustainable approach for efficient solar steam generation. With the continuous development of solar evaporation technology, the preparation of green and efficient photothermal materials has become a research hotspot. In this review, the photothermal materials were classified into metal materials, semiconductor materials, carbon-based materials and polymer materials according to their types. It elaborated on the photothermal conversion mechanisms of different materials and summarized the research status and progress of photothermal materials in the field of seawater desalination in recent years. The potential candidate photothermal materials were discussed and their future development was forecasted. This review aims to propose practical strategies for the rational design and development of efficient photothermal materials in the field of seawater desalination. The findings summarized in this review are of great significance for the future development of photothermal materials and provide valuable guidance for future research in this area. Fig. & Tab. | Reference | Related Articles | Metrics Review Research Progress of CO2 Capture and Separation by Functionalized Ionic Liquids and Materials★ Shaojuan Zeng, Xueqi Sun, Yinge Bai, Lu Bai, Shuang Zheng, Xiangping Zhang, Suojiang Zhang Acta Chimica Sinica 2023, 81 (6): 627-645. DOI: 10.6023/A23030063 Published: 27 April 2023 Abstract (766) HTML (66) PDF (4652KB)(1369) Knowledge map CO2 emission is a serious global problem. CO2 capture technology is indispensable to achieve the strategic goals of carbon peaking and carbon neutrality in China. Ionic liquids as new media have attracted much attention in the field of CO2 capture and separation due to their unique advantages of low volatility, good gas solubility and structure designability. This review focuses on research progresses of amino and non-amino functionalized ionic liquids, ionic liquid hybrid solvents, ionic liquid modified adsorbents and membranes for CO2 capture and separation reported in the past five years. The influence of amino groups and electronegative functional sites on CO2 separation performance and mechanism, and the role of functionalized ionic liquids in hybrid solvents, adsorbents and membranes were summarized. Finally, the future development direction and prospect of ionic liquid-based CO2 capture technologies were also proposed. Fig. & Tab. | Reference | Related Articles | Metrics Review Research Progress of Ion-initiated in situ Generated Solid Polymer Electrolytes for High-safety Lithium Batteries★ Zhixiang Yuan, Hao Zhang, Sijia Hu, Botao Zhang, Jianjun Zhang, Guanglei Cui Acta Chimica Sinica 2023, 81 (8): 1064-1080. DOI: 10.6023/A23030085 Published: 26 May 2023 Abstract (753) HTML (45) PDF (11712KB)(868) Knowledge map Lithium-ion batteries, widely used in many aspects of the national economy such as electric vehicles, mobile intelligent devices and large-scale energy storage, have gradually entered special applications area including deep sea, deep space, deep ground and individual combat equipment. However, lithium batteries using traditional carbonate liquid electrolytes often suffer from potential safety risk such as electrolyte leakage, flammability and explosion, so it is urgent to develop a new generation of high-safety solid electrolytes. Among them, solid polymer electrolytes have attracted great attention because of their superior mechanical flexibility and compatibility with the main production processes of lithium battery. In terms of preparation process, solid polymer electrolytes prepared via solution-casting often easily lead to high interfacial resistance and then deteriorate the battery performance. In contrast, liquid organic precursors used in in-situ polymerization strategy can sufficiently penetrate the positive and negative electrodes to guarantee superior interfacial compatibility and efficient ionic conduction. At present, most of in-situ polymerization strategies are based on free radical thermal polymerization with additional initiators and the need for harsh conditions such as high temperature. Ion polymerization can use lithium salt or lithium metal as an initiator at room temperature, thereby effectively avoiding the introduction of impurities. Up to now, researchers have made considerable research progress in the construction of solid polymer electrolytes by ion-initiated in situ polymerization. Hence, this review mainly summarizes the research progress of solid polymer electrolytes from the aspects of cationic polymerization and anionic polymerization. In addition, we also elaborates the challenges and development trends of solid polymer electrolytes through ion-initiated in situ polymerization for high-safety lithium batteries in the future. Fig. & Tab. | Reference | Related Articles | Metrics Perspective Perspective for Phosphine Ligands with Cyclopropane Backbone★ Yandong Zhang, Shoufei Zhu Acta Chimica Sinica 2023, 81 (7): 777-783. DOI: 10.6023/A23040125 Published: 17 May 2023 Abstract (741) HTML (16) PDF (1160KB)(441) Knowledge map Throughout the history of transition-metal catalysis, almost every breakthrough is closely related to the development of ligands. Therefore, the history of transition-metal catalysis roughly parallels the development history of ligands. Therefore, ligand development lies in the heart of transition metal catalysis. Since the beginning of homogeneous catalysis, transition metals have been accompanied by phosphine ligands (Wilkinson's catalyst). Till now, phosphine ligands are one of the most widely used ligand types. There are several key factors for the popularity of phosphine ligands, among which the backbone of ligand plays a decisive role in supporting their stability, activity and selectivity. Many privileged phosphine ligands contain five- or six-membered rings in their core structures, possibly due to their ready-availability, low ring strain, and high stability. Seven- and above membered cyclic structures have flexible frameworks, many stable conformations, and are difficult to synthesize, making them unsuitable as ligand backbones. The cyclobutane structure has relatively strong ring strain, but its conformation can be flipped, and it is difficult to synthesize, making it inappropriate to be used as a ligand skeleton, too. As the smallest all-carbon ring, the three carbon atoms of cyclopropane are located in the same plane. Because of the unique electronic structure and rigidity of cyclopropane, changing a substituent on any one of the carbon atoms of the ring will affect the conformation of the substituents on the other two carbons. And cyclopropane structure is relatively simple to synthesize and modify, making it a promising ligand skeleton. However, it is surprising that phosphine ligands with cyclopropane as the core structure have been rarely studied so far, and their applications need to be further explored, too. Based on types of ligands, this perspective systematically summarizes reported phosphine-containing ligands (including monophosphines, diphosphines, phosphine-heteroatoms and triphosphines) with cyclopropane backbone, and their applications in transition metal catalysis. We hope to draw researchers' attention to the cyclopropane-based phosphine ligands and thus promote the development of transition metal catalysis. Fig. & Tab. | Reference | Related Articles | Metrics Review Flexible Electrochemical Sensors and Their Applications in Noninvasive Medical Detection★ Huarun Liang, Haoxuan Ma, Xinrong Duan, Jie Yu, Haomin Wang, Shuo Li, Mengjia Zhu, Aibing Chen, Hui Zheng, Yingying Zhang Acta Chimica Sinica 2023, 81 (10): 1402-1419. DOI: 10.6023/A23060289 Published: 24 August 2023 Abstract (720) PDF (6657KB)(756) Knowledge map Electrochemical sensors are widely employed for the detection of substance concentrations owing to their rapid response, high sensitivity, remarkable selectivity, and ease of quantification. With the rapid advancements in flexible electronics technology, electrochemical sensors have been transitioned into flexible and wearable formats, facilitating the in-situ analysis of biological liquids or gases. This breakthrough has opened avenues for portable, noninvasive continuous monitoring of physiological parameters and health status, thereby unveiling vast potential in the realm of intelligent healthcare and medical applications. Building upon these remarkable progressions, this paper primarily focuses on the design and applications of flexible electrochemical sensors tailored specifically for noninvasive medical detection. Firstly, the basic components of flexible electrochemical sensors are elucidated. Subsequently, the working principles of various types of sensors are expounded upon. Furthermore, we systematically review the latest advancements in the detection of pivotal chemical substances in typical biofluids such as sweat, interstitial fluid, tears, saliva, and breath, using flexible electrochemical sensors. Finally, the challenges and opportunities of flexible electrochemical sensors for applications in noninvasive health monitoring and precision medicine are discussed and proposed. Reference | Related Articles | Metrics Review Recent Advance of Diazo Compounds in Polymer Synthesis★ Lefei Yu, Xing-Qi Yao, Jianbo Wang Acta Chimica Sinica 2023, 81 (8): 1015-1029. DOI: 10.6023/A23050244 Published: 25 June 2023 Abstract (705) HTML (42) PDF (1227KB)(929) Knowledge map Based on the well development of diazo compound transformations in organic synthesis, it is expected to extend its applications to the field of polymer synthesis. It is of vital importance to transform efficient organic reactions of diazo compounds into new polymerization methodology in order to afford polymers with new structures and functions. Currently, there is still great development potential in the application of diazo compounds in polymer synthesis. This review highlights the recent advancements of polymer synthesis chemistry with diazo compounds, including chain-growth polymerization, step-growth polymerization, end-group functionalization and post-polymerization modification. Transition-metal-catalyzed chain-growth polymerization of diazoacetates constructs C—C main chain from one carbon unit. Through the development of catalytic diazoacetate polymerization, the synthesis of high molecular weight polymers, stereocontrol polymerization and living/controlled polymerization can be realized successively. The stepwise polymerization of diazo compounds originated from their efficient organic conversions. The insertion reaction of diazo compounds into O—H and N—H bonds can be extended to stepwise polymerization to afford polyethers, polyesters and polyamines that are not easily accessible through other synthetic methods, while cross-coupling polymerization of diazo compounds via metal carbene insertion-migration mechanism can realize the synthesis of polymers with novel structures. Diazoacetates and diazomalonates can be employed to regulate the terminal structures of polymers synthesized through metal-catalyzed vinyl addition polymerization or ring-opening metathesis polymerization of olefins, and successively end-capped by metal carbene. The post-polymerization modifications based on diazo compounds can be applied to the introduction of polar functional groups into polyolefin. Compared to the copolymerization of polar olefins, the post-polymerization functionalization strategy avoids the depressed reactivity of varied monomers, and can be applicable to a broad scope of functional groups. The thermal and mechanical properties of polymers can be improved by this method. Finally, the future challenges in expanding the approaches on polymer chemistry of diazo compounds are prospected in this review. Fig. & Tab. | Reference | Related Articles | Metrics Review Surface Functionalization Based on Protein Amyloid-like Aggregation★ Chengyu Fu, Xingyu Zhou, Peng Yang Acta Chimica Sinica 2023, 81 (11): 1566-1576. DOI: 10.6023/A23060266 Published: 08 October 2023 Abstract (650) HTML (68) PDF (16249KB)(956) Knowledge map Surface modification plays a pivotal role across various domains by conferring novel properties and heightened value to materials, all while preserving their inherent characteristics. However, a critical impediment stalling the broader utilization and advancement of advanced interface materials is the absence of a simple, environmentally friendly, universally applicable, colorless and transparent interface modification system. Since the initial reports of employing amyloid-like proteins for interface modification, this approach has garnered considerable attention and research within the academic community. Subsequently, an array of protein-based materials featuring diverse morphological structures such as nanofilms, nanofibers, large particle aggregates, hydrogels, aerogels, and more have emerged. This review commences by elucidating the fundamental principles underlying amyloid-like protein aggregation. Subsequently, it provides a comprehensive summary of its applications as a surface modification system in various domains including biomedical coatings, separation and dialysis, biomineralization, flexible electronics, smart fabrics, chemical catalysis and environmental pollutant removal. Furthermore, it discusses the current application directions and ultimately highlights the system's limitations, concluding with a prospective outlook on its future development. Fig. & Tab. | Reference | Related Articles | Metrics Review Advances in Catalytic Asymmetric Reactions Involving o-Hydroxyphenyl Substituted p-Quinone Methides★ Shuang Yang, Ningyi Wang, Qingqing Hang, Yuchen Zhang, Feng Shi Acta Chimica Sinica 2023, 81 (7): 793-808. DOI: 10.6023/A23040192 Published: 15 June 2023 Abstract (646) HTML (27) PDF (1667KB)(663) Knowledge map o-Hydroxyphenyl substituted p-quinone methides (p-QMs) belong to a class of p-QMs with unique advantages. They not only maintain the high reactivity of p-QMs, but also have more reactive and activation sites owing to the introduction of hydroxyl group. Therefore, o-hydroxyphenyl substituted p-QMs have wide applications in synthetic and medicinal chemistry. The catalytic asymmetric 1,6-conjugate addition and [4+n] cycloaddition of o-hydroxyphenyl substituted p-QMs have developed very rapidly in recent years, which have become efficient strategies for the synthesis of chiral oxygen-containing heterocycles and arylmethanes with potential bioactivity. This review summarizes the catalytic asymmetric reactions involving o-hydroxyphenyl substituted p-QMs and points out the remaining challenges in this research area, which will open a new window for the design of new type of o-hydroxyphenyl substituted p-QMs and their involved catalytic asymmetric reactions. Fig. & Tab. | Reference | Related Articles | Metrics Review Development of Construction of Chiral C—X Bonds through Nickel Catalyzed Asymmetric Hydrogenation★ Xinhong Cai, Jianzhong Chen, Wanbin Zhang Acta Chimica Sinica 2023, 81 (6): 646-656. DOI: 10.6023/A23040140 Published: 15 May 2023 Online available: 15 May 2023 Abstract (631) HTML (20) PDF (1629KB)(693) Knowledge map Chiral C—X (X=N, O, P, B, F, etc.) bond fragments are present in a wide variety of natural and pharmaceutically active molecules. Transition metal-catalyzed asymmetric hydrogenation is one of the most attractive strategies for the synthesis of these chiral compounds. Among the many transition metal catalysts, earth-abundant transition metals (iron, cobalt, nickel, and copper) have been used in asymmetric hydrogenation to replace rare metals (rhodium, ruthenium, iridium and palladium) due to their abundant reserves, low toxicity, and environmental friendliness. At present, this method for the construction of chiral C—X bonds has become a prominent trend in modern organic chemistry. Among them, the development of nickel catalysts has been relatively rapid. Based on this, the article will review the latest research in the preparation of compounds with chiral C—X bonds via nickel-catalyzed asymmetric hydrogenation using hydrogen. It is divided into five sections consisting of the construction of chiral C—N, C—O, C—P, C—B and C—F bonds by nickel-catalyzed asymmetric hydrogenation. Fig. & Tab. | Reference | Related Articles | Metrics Review Self-assembly Fabrication and Applications of Photonic Crystal Structure Color Materials★ Liwei Hu, Xianhu Liu, Chuntai Liu, Yanlin Song, Mingzhu Li Acta Chimica Sinica 2023, 81 (7): 809-819. DOI: 10.6023/A23030080 Published: 10 May 2023 Abstract (631) HTML (47) PDF (6787KB)(693) Knowledge map Photonics crystals are structures composed of materials with different refractive indices arranged periodically. Due to their unique optical properties and excellent color saturation, they have become the most important type of structural color materials. In the past few decades, the fabrication of photonic crystals using self-assembly of nanoparticles has attracted widespread research attention due to its precision, low cost, and ease of large-scale production. The recent research progress on photonic crystal structural color materials, including their basic color production mechanisms, fabrication methods, and practical applications in displays, color sensing, and information anti-counterfeiting encryption is reviewed with focuses on the fabrication of photonic crystal structural colors using a “bottom-up” self-assembly approach. And the methods for producing photonic crystal patterns and large-area structural color films are emphasized. Finally, the challenges faced by current self-assembly fabrication of photonic crystal structural color materials and prospects for future development directions are discussed. Fig. & Tab. | Reference | Related Articles | Metrics Review Recent Advances in the Transformation of Difluorocyclopropenes★ Huang Jiapian, Liu Fei, Wu Jie Acta Chimica Sinica 2023, 81 (5): 520-532. DOI: 10.6023/A23030088 Published: 20 April 2023 Abstract (553) HTML (26) PDF (1220KB)(846) Knowledge map In recent years, organic reactions involving difluorocyclopropenes have attracted the attention of organic chemists and have made great progress. The reactions mainly include: (1) cyclization: a) transition-metal catalyzed C—H bond activation cyclization with directing groups; b) cyclization reactions with non-directing groups; (2) hydrogenation reduction; (3) fluorination as “F” source reagents. In this paper, the synthesis methods and applications of difluorocyclopropenes in past 10 years are summarized. The conversion reactions of difluorocyclopropenes are emphasized. Additionally, difluorocyclopropenes have aroused considerable interests both from a structural standpoint and their participation in various ring-opening reactions. Given the increasing application of cyclopropyl skeleton in the development of drugs and unarguable importance of fluorinated compounds in medicinal chemistry and agrochemistry, it is no doubt that difluorocyclopropenes are encountered into bioactive molecular and at present lie among “emerging fluorinated motifs”. Although the synthesis and application of structurally diverse difluorocyclopropenes have been witnessed in the past decade, the most widely used methods for the preparation of these compounds include difluoromethylenation of alkynes and difluoromethylation of heteroatom nucleophiles (such as NaF, NaI, nBuN4X, etc.) with a difluorocarbene reagent, which can be generated from various precursors (such as TMSCF3, TMSCF2X, Ph3P+CF2CO2-, TFDA, etc.). For the transition metal-catalyzed cyclization of difluorocyclopropenes, some common metal salts (such as rhodium, ruthenium, copper, palladium, silver) are used as catalysts. Moreover, the metallic hydrogen (M—H) reduction strategy is a simple and efficient method for the hydrogenation reduction of difluorocyclopropenes leading to difluorocyclopropanes, and the asymmetric hydrogenation reduction of difluorocyclopropenes can be achieved in the presence of chiral ligands. In fluorination reactions, difluorocyclopropenes have some advantages that cannot be achieved by traditional fluorination reagents for the direct fluorination and functionalization of hydroxyl groups (such as fluorination of polyhydroxyl alcohols). Of course, the biggest disadvantage of difluorocyclopropene as a fluorine source lies in its poor atomic economy, which has been criticized. Despite the remarkable achievements in the reactions of difluorocyclopropenes, there are still many issues that need to be addressed. For instance, difluorocyclopropenes are rarely applied in traditional radical reactions, photocatalysis, electrocatalysis and flow chemistry. Hopefully, difluorocyclopropenes can gradually appear in photo- and electro-catalyzed radical chemistry, and the related asymmetric reactions will also get more attention and development in the near future. Fig. & Tab. | Reference | Related Articles | Metrics Review Research Progress on the Preparation of Metal-Organic Frameworks Encapsulated Metal Nanoparticle Composites and Their Catalytic Applications★ Fengbin Zheng, Kun Wang, Tian Lin, Yinglong Wang, Guodong Li, Zhiyong Tang Acta Chimica Sinica 2023, 81 (6): 669-680. DOI: 10.6023/A23040146 Published: 26 May 2023 Abstract (531) HTML (38) PDF (5504KB)(614) Knowledge map Metal-organic frameworks (MOFs) are characteristic of high specific surface area, abundant metal nodes, diverse organic ligands, and ordered pore structure. More importantly, its composition and structure are easy to be designed and controlled, so it is very promising to become a new class of catalytic carrier materials. In recent years, the composites of metal nanoparticles encapsulated by MOFs have attracted great attention in the field of catalysis due to their unique structural features. However, more in-depth and systematic research is still needed in terms of its precise preparation and the relationship of the structure and catalytic performance. Based on above, the recent research progress on the preparation methods of metal nanoparticles encapsulated by MOFs and their catalytic applications are systematically summarizd. First, the synthesis methods of metal nanoparticles encapsulated by MOFs are summarized. Then, the catalytic applications are discussed in term of synergy among metal nanoparticles, pore structure, organic ligands or/and metal nodes of MOFs. Moreover, the relationships among active component, structure and their properties are illustrated. Finally, the challenges, opportunities and future development prospects of this research direction are discussed from the aspects of synthesis methods and catalytic applications. Fig. & Tab. | Reference | Related Articles | Metrics Review Heterogeneous Catalysts for Selective Hydrogenolysis of Biomass-derived Polyols★ Liu Lujie, Zhang Jian, Wang Liang, Xiao Fengshou Acta Chimica Sinica 2023, 81 (5): 533-547. DOI: 10.6023/A23020042 Published: 28 March 2023 Online available: 28 March 2023 Abstract (528) HTML (29) PDF (7803KB)(477) Knowledge map Catalytic transformation of biomass-derived polyols into valuable chemicals has attracted attention from the viewpoint on using renewable carbon resources. Therefore, it is important for design and preparation of heterogeneous catalysts with high activity, high selectivity, and high stability for the selective conversion of biomass-derived polyols. Recently, it has been reported the selective production of mono-alcohols and/or diols by selective hydrogenolysis of sugar alcohols, where the Ir-ReOx and Pt-WOx as typical heterogeneous catalysts are highly efficient. In this review, we briefly summarized the routes for the selective conversion of sugar alcohols into mono-alcohols and/or diols, where the metal-metal oxide interaction for catalyst design, relationship between catalyst structure and performance, and reaction mechanism for the C—O hydrogenolysis are particularly discussed. In addition, the future trend for the selective hydrogenolysis of sugars is also prospected. This review might be helpful for design of novel heterogeneous catalysts in sugar alcohol conversion. Fig. & Tab. | Reference | Related Articles | Metrics Review Advances in Electrochemical Reductive Removal of Oxyanions in Water★ Wei Hou, Yancai Yao, Lizhi Zhang Acta Chimica Sinica 2023, 81 (8): 979-989. DOI: 10.6023/A23040133 Published: 12 June 2023 Abstract (525) HTML (20) PDF (2667KB)(622) Knowledge map The excessive discharge of oxyanions (i.e., nitrate, bromate, perchlorate) into water has caused more and more serious environmental pollution problems. Oxyanions are generally persistent, refractory, teratogenic and carcinogenic, posing a great threat to ecosystems and human health. Therefore, they have increasingly attracted widespread attention. Electrochemical reduction is regarded as one of the most promising water treatment technology, because it could employ either electrons or strong reductive species (atomic H*) generated by dissociating water molecules to realize the efficient, green and safe removal of toxic oxyanions. Herein, the electrochemical reduction mechanism for removing pollutants is briefly introduced, the advancements of electrochemical reduction of nitrate, bromate and perchlorate are summarized and their possible reaction pathways are discussed, the effect of catalysts (i.e., structure, types) on the performance of electrochemical reduction is further analyzed. Finally, the possible challenges of electrochemical reduction technology to remove oxyanions are deeply discussed and prospected. Fig. & Tab. | Reference | Related Articles | Metrics Article Light-Responsible Room-Temperature Phosphorescence Materials Based on Diarylethene★ Liu Yiwei, Ma Liangwei, Wang Qiaochun, Ma Xiang Acta Chimica Sinica 2023, 81 (5): 445-449. DOI: 10.6023/A23030077 Published: 10 April 2023 Abstract (524) HTML (31) PDF (1856KB)(591) Knowledge map Photochromic molecules show great potential in biological imaging, logic gates, super-resolution imaging and other fields due to the sensitivity, accuracy and penetrability of light. By utilizing their variations on physical properties upon light irradiation, the fluorescence signal of photochromic dyes can be turned on or off accurately by specific wavelength. As an important luminescent dye, organic room-temperature phosphorescence (RTP) materials have attracted great research interest of scientists by the triplet state radiation process, and have potential in sensing, anticounterfeiting, photo-dynamic therapy, and so forth. In this work, we combine the phosphorescence and photochromic properties together by connecting a classic photochromic dye (bithienylethene) with an efficient phosphor (thiochroman-4-one) via sp2 and sp3 linker (BTE1oand BTE2o). These compounds show typical photochromic phenomenon in solution and polymer matrix and have good fatigue resistance. During the irradiation, a clear isosbestic point can be observed, indicating the quantified transition between two isomers. The emission quenching of derivatives is considered as the radiative energy transfer between fluorescent open form and non-fluorescent closed form. It’s interesting that the fluorescence lifetime of BTE1oand BTE2oincreases after ultraviolet (UV) irradiation, which rules out the possibility of non-radiative energy transfer mechanism of the fluorescence quenching phenomena. In the poly(vinyl alcohol) (PVA) matrix, these compounds show decent RTP emission and millisecond level lifetime. And the RTP emission can also be reversibly turned “ON” or “OFF” via irradiation of different wavelengths. It’s very interesting that the phosphorescence lifetime also increases (from 16.1 to 19.4 ms) with the irradiation of UV light, which is identified with the variation of fluorescence lifetime in solution and PVA matrix. The increase of lifetime can rule out the non-radiative energy transfer mechanism for the phosphorescence quenching phenomena. Considering the fluorescence quenching phenomena in tetrahydrofuran (THF) solution, the fluorescence and phosphorescence quenching in PVA matrix should also be attributed to the form conversion and the radiative energy transfer process between open and closed isomers. Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Communication Catalytic Synthesis of Polyolefin Elastomer Using Unsymmetrical α-Diimine Nickel Catalyst★ Zihao Wang, Min Chen, Changle Chen Acta Chimica Sinica 2023, 81 (6): 559-564. DOI: 10.6023/A23040162 Published: 02 June 2023 Abstract (490) HTML (19) PDF (1313KB)(471) Knowledge map Since the discovery of Ziegler-Natta catalyst, great breakthrough has been made in the design of catalyst in olefin polymerization field, but the development of catalyst is still the fresh source in this field. It will always be a frontier scientific problem in this field to influence the olefin polymerization process through the structural design of catalysts. Due to the low cost of nickel and its high abundance, nickel-based catalysts have shown great prospects in the application of olefin polymerization. In this work, three kinds of unsymmetrical α-diimine nickel catalysts with different steric effects were designed, and their catalytic performances in ethylene polymerization were explored. It is found that the variety of catalysts and the change of polymerization conditions have important effects on the catalytic activity of ethylene polymerization, the molecular weight, branching density, thermodynamic parameters and mechanical properties of the prepared polyethylene. Among them, the polyolefin prepared by Ni3 catalyst with large steric hindrance is ultra-high molecular weight polyethylene, and the above materials maintain excellent mechanical properties and elastic properties at the same time. Specifically, tert-butyl substituted ketoimine intermediate B was condensed with three different anilines to synthesize ligands L1~L3 with different steric effects. The catalysts Ni1~Ni3 were successfully synthesized by efficient coordination reaction between the obtained ligands and DMENiBr2, and the yields were over 90%. The single crystal structures of catalysts Ni1 and Ni3 were also prepared, and the steric hindrance around the nickel center was quantified utilizing the steric maps [Vbur(Ni1)=46.1%, Vbur(Ni3)=48.7%]. Under 0.8 MPa pressure of ethylene and AlEt2Cl as cocatalyst, the ethylene polymerization performance was explored using three nickel catalysts at different temperatures. Among them, Ni2 exhibited the best catalytic activity in ethylene polymerization at 50 ℃ (up to 1.7×107 g•mol-1•h-1), generating polyethylene with higher branching density. The polyethylene prepared by Ni3 with large steric hindrance is ultra-high molecular weight polyethylene with a molecular weight of 172×104 g•mol-1. Moreover, polyethylene materials prepared by Ni3 also showed excellent mechanical properties (breaking stress, 6~8 MPa; elongation at break, ≈600%) and elastic properties (strain recovery value up to 68%). Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Review Recent Advances in Multiple Resonance Organic/Polymer Fluorescent Materials with Narrowband Emission★ Yinuo Wang, Shiyang Shao, Lixiang Wang Acta Chimica Sinica 2023, 81 (9): 1202-1214. DOI: 10.6023/A23040186 Published: 07 July 2023 Abstract (477) HTML (25) PDF (1254KB)(796) Knowledge map Multiple resonance (MR) emitters can be considered as intramolecular push-pull electronic systems formed by embedding electron-deficient atoms and electron-rich atoms in polycyclic aromatic skeleton. Since the structural relaxation of excited state is suppressed by the rigid molecular skeleton, multiple resonance emitters exhibit the prominent feature of narrowband emission, which enables them to attract wide attention of researchers since its report. Up to now blue, green and red multiple resonance emitters with both high device efficiency and high color purity were developed, making them become an important research direction for organic/polymeric fluorescent materials. In this review, recent advances in narrowband multiple resonance emitters are summarized from the perspective of materials and devices, with focus on B/N-, B/O(S)-, C=O/N-containing and indolocarbazole-based multiple resonance emitters. The effects of elements composition, molecular framework and substituents on their luminescent characteristics and device performances are summarized. Meanwhile, opportunities and challenges for future development of multiple resonance emitters are analyzed and prospected. Fig. & Tab. | Reference | Related Articles | Metrics Perspective Palladium(II)-Catalyzed Enantioselective Functionalization of C(sp3)—H Bonds★ Yeqiang Han, Bingfeng Shi Acta Chimica Sinica 2023, 81 (11): 1522-1540. DOI: 10.6023/A23070336 Published: 12 September 2023 Abstract (467) HTML (15) PDF (1432KB)(608) Knowledge map Chiral molecules are ubiquitous in nature and play an important role in natural products, pharmaceuticals, agriculture, advanced materials, as well as living organisms. Therefore, the development of efficient strategies to enable the facile construction of enantiopure chiral compounds in an atom- and step-economical manner is of great importance. The enantioselective functionalization of C—H bonds without multi-steps transformation is arguably one of the most powerful and straightforward strategies to fulfill this goal. This emerging research field has been rapidly developed with the innovation of various chiral catalysts and/or ligands in recent years. In particular, significant advances have been achieved in palladium-catalyzed enantioselective functionalization of C(sp3)—H bonds, streamlining the efficient and concise construction of chiral molecules from readily available hydrocarbon feedstocks. The stereoselective functionalization of C(sp3)—H bonds with the assistance of chiral ligand to form a chiral palladacycle intermediate, which could be transformed into various chemical bonds to form functionalized chiral compounds, has attracted tremendous attention. Thus, this perspective summarizes the advances on palladium(II)-catalyzed enantioselective functionalization of C(sp3)—H bonds via asymmetric C—H palladation. According to the type of C—H bonds, this perspective is classified into several sections, including methyl C(sp3)—H bonds, methylene C(sp3)—H bonds in constrained cycloalkanes, functionalization of methylene C(sp3)—H bonds adjacent to α-heteroatom, benzylic methylene C(sp3)—H bonds, and unbiased methylene C(sp3)—H bonds. The emphasis of this perspective focuses on the discussion of the philosophy of developing novel chiral ligands and the mode of stereocontrol. The remaining limitations and challenges regarding to chemo- and enantioselective control in this field is also discussed. Further development of new chiral ligands and catalytic systems is expected to address these issues and expands the scope of this powerful synthetic strategy. We anticipate that this perspective might inspire more efforts to this emerging research field and the strategy might find wide applications in the synthesis of complicated chiral molecules, such as natural products and drugs. Fig. & Tab. | Reference | Related Articles | Metrics Review Reserach Advances on Nanozyme-Guided Therapy of Inflammatory Bowel Diseases★ Qiwen Chen, Xianzheng Zhang Acta Chimica Sinica 2023, 81 (8): 1043-1051. DOI: 10.6023/A23040144 Published: 07 June 2023 Abstract (455) HTML (24) PDF (2916KB)(703) Knowledge map Recently, the increasing morbidity of inflammatory bowel diseases (IBD) has become a threat to public health around the world. At present, anti-inflammatory drugs, antibiotics, biological antibodies, and immunomodulators are widely used to treat IBD through suppressing inflammation response, but the therapeutic effects are not always satisfied. Biological enzymes have highly efficient and specific catalytic activity, which has aroused extensive research interest in diagnosis and treatment of inflammatory diseases. However, bioenzymes are difficult to be purified and are easy to be inactivated within organism, which limits its further applications. Compared with bioenzymes, nanozymes have simple preparation procedure, stable structure and high enzyme-like catalytic activity. Very recently, nanozymes have been widely used in the field of biomedicine, such as anti-cancer, antibacterial, anti-inflammation and so on. In this review, recent research advances of nanozymes for treatment of IBD are summarized by introducing typical studies, focusing on the composition, synthesis methods, catalytic properties and therapeutic mechanisms of the used nanozymes. This review also discusses the limitations of the current application of nanozymes for the treatment of IBD, and the prospect of the future construction of nanozymes for treatment of IBD. Fig. & Tab. | Reference | Related Articles | Metrics Review Progress and Environmental Research Applications of Cryo-Electron Microscopy★ Yujie Yang, Yuxiu Gong, Tianhang Gu, Wei-xian Zhang Acta Chimica Sinica 2023, 81 (8): 990-1001. DOI: 10.6023/A23040166 Published: 28 June 2023 Abstract (452) HTML (29) PDF (5287KB)(620) Knowledge map Electron microscopy (EM) is one of the most important techniques to characterize the morphology and structure of micro- and nano-particles. However, conventional procedures for sample preparation often alter the structure and morphology of samples with high water contents, causing distortions and misinterpretations for EM characterizations. The invention of Cryo-electron microscopy (Cryo-EM) has largely solved this problem. Via rapidly freezing the hydrated samples at low temperatures, cryogenic techniques instantaneously transform liquid water into amorphous ice to ensure high vacuum and reduce electron radiation damage, allowing researchers to observe hydrated samples in their native state with high resolution. For example, applications of Cryo-EM during the COVID-19 pandemic have demonstrated the amazing ability of Cryo-EM to visualize the detailed structure of SARS-CoV-2 viruses, which provides vital knowledge for rapid and reliable detection and diagnosis of the disease, transmission mitigation, and vaccine development. So far, Cryo-EM technology has been widely used in materials, biology, pharmaceuticals, and other fields of research, successfully broadening and deepening the understanding of the interactions between micro- and nano-particles. This review summarizes the recent development of Cryo-EM from aspects of electronic components, imaging technology, and resolution and introduces the sample preparation methods. Furthermore, the three-dimensional reconstruction method is highlighted to advance the EM method from 2D to 3D. As most environmental samples are highly hydrated, Cryo-EM will likely become an essential tool to investigate microscopic particles in the environmental field. This review gives examples of the applications of Cryo-EM in the formation of aerosol particles in the atmosphere, observing biofilm morphology in the water treatment process, the pore structure of activated sludge flocs, and the potential mechanism of soil microorganisms on heavy metal remediation. Finally, the prospects of Cryo-EM are summarized and discussed. We expect that with software, hardware, and artificial intelligence development, Cryo-EM technology can achieve faster data acquisition and higher resolution and make breakthrough contributions to environmental chemistry research. Fig. & Tab. | Reference | Related Articles | Metrics Communication Brønsted Acid-Catalyzed Intramolecular Hydroalkoxylation/Claisen Rearrangement of Ynamides★ Tongyi Zhai, Chang Ge, Pengcheng Qian, Bo Zhou, Longwu Ye Acta Chimica Sinica 2023, 81 (9): 1101-1107. DOI: 10.6023/A23040188 Published: 13 June 2023 Abstract (446) HTML (115) PDF (633KB)(457) Knowledge map A Brønsted acid-catalyzed intramolecular hydroalkoxylation/Claisen rearrangement of ynamides for the synthesis of eight-membered lactams is presented. Firstly, the keteniminium intermediate was generated from the activation of ynamide by Brønsted acid, which could interact with intramolecular hydroxy group through hydrogen bonding and ion pairing effects. Then, the tandem hydroalkoxylation/Claisen rearrangement took place and produced eight-membered lactams. Meanwhile, preliminary studies were conducted into the chiral Brønsted acid-catalyzed kinetic resolution, and several chiral eight-membered lactams were successfully synthesized. Other notable features of this metal-free method include the simple procedure, mild reaction conditions and good functional group compatibility. This research provides a practical method for the synthesis of biologically important eight-membered lactam skeletons. Accordingly, MsOH (5 mol%, 0.005 mmol, 0.32 μL) was added to the solution of ynamide (1 equiv., 0.1 mmol) in dry PhCl (4 mL) at room temperature. The reaction mixture was then stirred at 60 ℃ and the progress of the reaction was monitored by thin layer chromatography (TLC). Upon completion, the reaction was quenched with Et3N (0.005 mmol, 0.7 μL), concentrated and purified by chromatography on silica gel (eluent: petroleum ether/ethyl acetate, V∶V=5∶1), to afford the desired eight-membered lactam. Under this condition, a series of ynamides with different substituents worked smoothly to provide the corresponding eight-membered lactams efficiently. Furthermore, chiral Brønsted acid (10 mol%, 0.005 mmol, 3.5 mg) and H2O (0.05 mmol, 0.9 μL) were added to the solution of ynamide (1 equiv., 0.05 mmol) in PhCl (2 mL) at –20 ℃ and the progress of the reaction was monitored by TLC. Upon completion, the reaction was quenched with Et3N (0.005 mmol, 0.75 μL), concentrated and purified by chromatography on silica gel (eluent: petroleum ether/ethyl acetate, V∶V=5∶1), to afford the chiral eight-membered lactam and chiral substrate. Also, a plausible mechanism involving the hydrogen bonding and ion pairing effects is proposed based on experimental results. Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Article Chromium-Catalyzed Carbonyl-Carbonyl Deoxygenative Couplings of Ketones to Tetrasubstituted Olefins★ Yuan Fangyan, Li Chao, Luo Meiming, Zeng Xiaoming Acta Chimica Sinica 2023, 81 (5): 456-460. DOI: 10.6023/A23020048 Published: 23 May 2023 Online available: 24 May 2023 Abstract (441) HTML (18) PDF (582KB)(445) Knowledge map Tetrasubstituted olefins are industrially important building blocks, which have been widely used in material and medicinal chemistry. Strategies that enable access to olefins have been developed, including the classic McMurry reactions of ketones using organotitanium reagents. The development of McMurry-type reactions using earth-abundant metals as catalysts, by the homo- and cross-couplings of two carbonyls in the deoxygenative fashion, would be a value-addition to tetrasubstituted olefins. Herein, we report the deoxygenative couplings of ketones that are enabled by cost-effective chromium catalysis. These couplings occur with low-cost Cr salt as precatalyst, 4,4'-di-tert-butyl-2,2'-bipyridyl (dtbpy) as ligand, metallic Mg as reductant, and trimethylchlorosilane (TMSCl) as additive. The protocols can be applied to achieve both homo- and cross-coupling of ketones, allowing for the efficient formation of sterically demanding tetrasubstituted olefins in one-step operation. Based on our experimental results and known reports, a plausible mechanism involving in the Cr-catalyzed deoxygenative couplings of ketones was proposed, wherein the reactive silachromate(I) might be formed by reaction of low-valent Cr species with Mg and trimethylchlorosilane, and is detected by high-resolution mass spectrometry analysis. It adds to unsaturated carbonyl of ketone in giving silyloxy-substituted (alkyl)Cr intermediate, followed by process of carbometalation by the addition of C—Cr bond to carbonyl of another ketone molecule. The C=C bond is formed by following deoxygenation in giving tetrasubstituted olefin product. Trimethylchlorosilane plays important roles in the ketone deoxygenative coupling, by the formation of reactive silachromate in responsibility for the addition and deoxygenation processes. The general procedure for the deoxygenative homocoupling is as following: in a dried Schlenk tube are placed ketone 1 (0.4 mmol), CrCl2 (5 mg, 0.04 mmol), dtbpy (10 mg, 0.04 mmol), Mg (20 mg, 0.8 mmol) and TMSCl (50 µL, 0.4 mmol) under atmosphere of nitrogen. After the addition of freshly distilled tetrahydrofuran (THF, 2 mL) by syringe, the resulting mixture was stirred at 90 ℃ for 12 h. The volatiles were removed under reduced pressure, and the crude product was purified by silica gel chromatography to give the corresponding tetrasubstituted olefin. Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Perspective Research Progress on Copper-Catalyzed Enantioselective Desymmetrization of Diols★ Zhanglong Yu, Zhongliang Li, Changjiang Yang, Qiangshuai Gu, Xinyuan Liu Acta Chimica Sinica 2023, 81 (8): 955-966. DOI: 10.6023/A23040161 Published: 13 June 2023 Abstract (434) HTML (24) PDF (1255KB)(453) Knowledge map Enantioselective desymmetrization of diols is an important method for the synthesis of complex enantioenriched alcohols, which has broad application prospects in medicinal chemistry, total synthesis, and materials science. In recent years, the use of copper catalysis to achieve diols’ enantioselective desymmetrization has progressed rapidly because copper is inexpensive and readily available compared with other noble metal catalysts. Besides, copper undergoes a two-electron or single-electron transfer process in the catalytic cycle, and the rich oxidation states of copper provides the opportunity to solve some challenging problems. This review summarizes the research progress in this field according to the types of diols (meso diol and prochiral diol) and reactions together with a brief perspective. Fig. & Tab. | Reference | Related Articles | Metrics Review Theory of Anomalous Diffusion Dynamics in Biomacromolecular Media★ Wenjie Wei, Wenlong Chen, Xiaobin Dai, Li-Tang Yan Acta Chimica Sinica 2023, 81 (8): 967-978. DOI: 10.6023/A23040172 Published: 02 June 2023 Abstract (425) HTML (19) PDF (6471KB)(319) Knowledge map Diffusion behavior in life system involves important life processes such as nutrient uptake and drug delivery. A deeper understanding about diffusive behavior of particles in complex biomacromolecular media will facilitate the understanding of relevant life phenomena as well as the development of novel medical materials. The diffusion behavior in biomacromolecular media is often anomalous and cannot be described simply based on the conventional diffusion constant equation. This is usually attributed to the continuous correlation of diffusion caused by crowded environment and complex interactions in biological medium, which leads to the central limit theorem no longer applicable. The mechanism and physical characteristics of anomalous diffusion were analyzed from three aspects: diffusion coefficient, mean square displacement, and displacement probability distribution function. The recent progress of anomalous diffusion in biomacromolecular media was summarized. The physical model and existing theoretical framework of anomalous diffusion are then outlined. Finally, the future direction of anomalous diffusion dynamics in biomacromolecular media is discussed. Fig. & Tab. | Reference | Related Articles | Metrics Review Recent Advances in Catalytic Enantioselective Synthesis of α-Chiral Tertiary Azides★ Yang Gao, Xuexin Zhang, Jinsheng Yu, Jian Zhou Acta Chimica Sinica 2023, 81 (11): 1590-1608. DOI: 10.6023/A23070359 Published: 08 October 2023 Abstract (424) HTML (7) PDF (1556KB)(437) Knowledge map α-Chiral azides are widely used in the fields of synthetic chemistry, medicinal chemistry and life science. Owing to α-chiral azides can be used for the diverse synthesis of α-chiral amine derivatives and nitrogen-containing heterocycles, and its azido group is also a pharmacophore, the efficient synthesis of α-chiral azides is highly important for drug discovery and development. Along with the incorporation of chiral quaternary carbon that can increase the three-dimensional stereospecificity of molecules has become an effective strategy to improve the bioactivity and druggability in drug design and development, the development of catalytic asymmetric synthetic methods toward α-chiral tertiary azides featuring aza-quaternary carbon center is highly desirable to facilitate drug research. However, due to the adverse steric effects caused by the structure of azido group that is close to a straight line, and the challenge of distinguishing the substituents with less difference to construct the aza-quaternary carbon stereocenter, the catalytic asymmetric protocols with high enantioselectivity are relatively scarce. This review aims to summarize the advances of the past five years according to the following two strategies: asymmetric functionalizations of C—N3 bond containing compounds and asymmetric azidations involving C—N3 bond forming, as well as discusses the possible reaction mechanism, the advantages and disadvantages of different reactions, which would provide some references and inspiration for researchers engaged in organic synthesis and medicinal chemistry. Fig. & Tab. | Reference | Related Articles | Metrics Review Structure and Properties Regulation of Organic Photosensitizers and Application in Photodiagnosis and Treatment★ Yinghong Yan, Pingzhao Liang, Yang Zou, Lin Yuan, Xiaojun Peng, Jiangli Fan, Xiaobing Zhang Acta Chimica Sinica 2023, 81 (11): 1642-1662. DOI: 10.6023/A23050243 Published: 21 July 2023 Abstract (421) HTML (26) PDF (5991KB)(718) Knowledge map Photodynamic therapy (PDT), as an efficient treatment method, has the advantages of low toxicity, non-invasiveness and controllability, which has been widely used in the treatment of proliferative skin diseases and tumors. However, the reported PDT photosensitizers still face many challenges in practical biological applications, such as the efficacy of PDT is significantly reduced by the tumor hypoxic environment; the poor targeting of photosensitizers can easily cause damage to normal tissues. In order to solve the above problems, researchers have proposed many effective strategies to improve the therapeutic efficacy of organic photosensitizers. Herein, the structure and property regulation strategies of organic photosensitizers are reviewed. In addition, the practical applications of photosensitizers in antitumor, antibacterial therapy, and afterglow imaging are introduced. In the end, the design strategies of organic small molecule photosensitizers are summarized and prospected in order to promote the development of this field. Fig. & Tab. | Reference | Related Articles | Metrics Communication Ru/Quartz Filter Paper: A Recyclable Photothermocatalytic Film for CO2 Methanation★ Ruxin Tian, Miao Yang, Guo Chen, Jiangshan Liu, Mengmei Yuan, Hong Yuan, Shuxin Ouyang, Tierui Zhang Acta Chimica Sinica 2023, 81 (8): 869-873. DOI: 10.6023/A23050200 Published: 11 July 2023 Abstract (418) HTML (76) PDF (2056KB)(514) Knowledge map Photothermocatalysis provides a green approach to convert solar energy to chemical energy. In previous studies, the most catalysts were powdered particles, which faces a problem that the light irradiation cannot reach the underlying catalysts, thereby making these catalysts not exhibit activity. A possible resolution to this difficulty is to load active phase on a thin substrate. In this study, a photothermocatalytic film of Ru/quartz filter paper (abbreviated as QFP) was designed, in which the Ru particles were loaded on a QFP with a thickness as thin as 0.36 mm. A photothermal synthesis was adopted to load the Ru particles. A 5 μL of precursor of RuCl3 ethanol solution was dripped on the QFP and then the QFP was dried under the irradiation of Xe lamp; this operation was repeated until all the precursor were loaded. After that, the QFP with Ru precursor was reduced in an atmosphere of H2/Ar mixture [V(H2)∶V(Ar)=1∶9] at photothermal 400 ℃ for 30 min. The loading mass of Ru particles were optimized by loading 1, 2, 3, and 4 mg of Ru on QFP to fabricate four samples. The X-ray diffraction (XRD) measurement revealed that the QFP was amorphous while the loaded Ru particles were metallic. The scanning electronic microscopy (SEM) indicated that the Ru particles were loaded on the SiO2 fiber of QFP steadily and most of Ru particles possessed a size less than 200 nm. Next, the photothermocatalytic CO2 methanation was carried out over the as-prepared catalysts to assess their catalytic activity. The catalyst with 2 mg Ru loading showed the highest performance; it delivered an 85.5% of CO2 conversion during 2 h of light irradiation. Although the four samples exhibited different CO2 conversion, the selectivities for CH4 product over these samples were all close to 100%. The stability of optimal catalyst was tested in a flow-type reaction system; under a 5 mL•min-1 flow rate of reactant gases, the CO2 conversion over the catalyst could remain around 51% during 12 h and the apparent CH4 yield rate reached 478.1 mmol•gRu-1•h-1. This study demonstrates a photothermal synthesis of recyclable Ru/QFP film and its application of photothermocatalytic CO2 methanation, which provides an energy-efficient process to achieve decarbonization and therefore is of great potential for practical application. Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Communication Gold/Iridium Catalyzed Alkynylamide Cyclization/Asymmetric Allylic Benzylation Cascade Reaction★ Wang Rui-Xiang, Zhao Qing-Ru, Gu Qing, You Shu-Li Acta Chimica Sinica 2023, 81 (5): 431-434. DOI: 10.6023/A23030103 Published: 09 May 2023 Abstract (417) HTML (273) PDF (547KB)(403) Knowledge map Asymmetric allylic substitution reactions involving benzyl nucleophilic reagents can rapidly construct chiral molecules containing benzyl fragments, which has attracted widespread attention from organic chemists. Formal asymmetric allylic benzylation reactions have been achieved by utilizing methylene oxazole as an equivalent of benzyl nucleophile. However, the development of highly efficient asymmetric allylic benzylation reactions remains a great challenge mainly due to the poor stability and synthetic difficulty of methylene oxazole. In this work, we have developed gold- and iridium- catalyzed alkynylamide cyclization/asymmetric allylic benzylation cascade reactions. In the presence of gold-carbene complex (Au1) and the combination of [Ir(cod)Cl]2 and (Sa)-Carreira ligand, a wide range of enantioenriched oxazole derivatives, bearing a benzylic stereogenic center, were obtained in 49%~87% yields with 98%~>99% ee. A general procedure is described as the following: To a dried Schlenk tube were added [Ir(cod)Cl]2 (5.4 mg, 0.008 mmol, 4 mol%), (Sa)-L1 (16.2 mg, 0.032 mmol, 16 mol%) and 1,2-dichloroethane (1 mL) under argon atmosphere. The mixture was stirred at room temperature for 15 minutes to give a chiral iridium complex solution. Under an argon atmosphere, alkynylamide (0.2 mmol, 1.0 equiv.), allyl alcohol (0.4 mmol, 2.0 equiv.), Au1 (0.02 mmol, 12.4 mg, 10 mol%), Fe(OTf)2 (0.2 mmol, 70.6 mg, 1.0 equiv.) and 3 Å molecular sieves (80.0 mg) were added to another dry Schlenk tube, and then the above-prepared iridium catalyst was added. The reaction mixture was stirred at 40 ℃ until the starting materials were consumed (monitored by thin layer chromatography, TLC). The mixture was quenched with water (5 mL), and extracted with dichloromethane (5 mL×3). The combined organic layers were dried over anhydrous Na2SO4, filtered, and then concentrated in vacuo to afford the crude product. The residue was purified by column chromatography (V(petroleum ether)/V(ethyl acetate)=15/1 or 10/1) to afford product 3. Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Communication Selectively Aerobic Oxidation of Benzylic C—H Bonds Enabled by Dual Anthracene and Cerium Catalysis under Continuous-Flow Conditions★ Xu Yuanli, Pan Hui, Yang Yi, Zuo Zhiwei Acta Chimica Sinica 2023, 81 (5): 435-440. DOI: 10.6023/A23030099 Published: 10 May 2023 Abstract (414) HTML (23) PDF (1594KB)(550) Knowledge map The benzyl oxidation reaction serves as a crucial functional group transformation method in the field of organic synthesis. Regrettably, traditional benzyl oxidation reactions frequently necessitate harsh conditions, such as elevated temperatures and potent oxidizing agents. In contrast, this article showcases a highly selective catalytic benzylic oxidation executed within a continuous-flow microreactor. By harnessing the previously established cerium-alcohol complex’s ligand to metal charge transfer (LMCT)-hydrogen atom transfer (HAT) activation mechanism and the anthracene-cerium synergistic catalytic system, a diverse array of aromatic ketones was synthesized from aryl alkanes with remarkable efficiency under ambient and aerobic conditions. The continuous-flow technology, endowed with unique advantages such as heightened illumination efficiency, superior gas-liquid mass transfer, repeatability, and scalability, has emerged as a powerful instrument for scaling-up photocatalytic reactions. In this process, under flow conditions, ethyl acetate solutions comprising Ce(NO3)3•6H2O, tetrabutylammonium bromide (TBABr), 9,10-dibromoanthracene (DBA), trichloroethanol (TCE), and ethylbenzene encountered and mixed with oxygen within the microreactor. Subsequently, a photocatalytic aerobic oxidation reaction occurred under visible light irradiation at room temperature, achieving complete conversion within a mere 5 min, and rapidly generated a series of aromatic ketones with good to excellent yields. Mechanistic studies indicated the paramount importance of the anthracene-derived catalyst DBA in achieving the heightened efficiency. Under visible light irradiation, the excited state DBA was initially oxidatively quenched with oxygen or peroxide species generated in the system, resulting in the formation of the DBA cationic free radical. Subsequently, the DBA cationic free radical underwent a single electron transfer (SET) process with the low-valent cerium (III) complex, consequently expediting the oxidative regeneration of the cerium (IV) catalyst and markedly boosting its catalytic efficacy. Eventually, this highly efficient catalytic system is characterized by its simplicity, mild reaction conditions, elevated selectivity, minimal waste production, and extensive applicability. Furthermore, it is effortlessly scalable and amenable to continuous production. Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Review Recent Advances in the Nacre-inspired Layered Polymer Nanocomposites by Ice Templating Technique★ Huagao Wang, Qunfeng Cheng Acta Chimica Sinica 2023, 81 (9): 1231-1239. DOI: 10.6023/A23050207 Published: 28 June 2023 Abstract (404) HTML (24) PDF (4250KB)(439) Knowledge map Ice templating, known as directional freeze casting, is a novel technique for constructing laminar porous materials by homogeneously dispersing or dissolving the building blocks, solvents and additives and using the “liquid-solid-gas” phase transition of the solvent. Inspired by the “brick-mortar” layered structure, the lamellar scaffold prepared from ice templating can be densified to construct nacre-like composite. This work presents a timely and systematic investigation and summary of frontier progresses of layered polymer nanocomposites constructed by the ice templating technique. Firstly, the densification strategies are classified according the different thickness of “brick” into three strategies: lamellar scaffold-filled polymer, hot-pressing treatment and mineralization. And typical layered polymer nanocomposites constructed by each strategy and their properties are also presented with classical examples. Subsequently, the design and functional applications of layered polymer nanocomposites are analyzed and discussed, such as the modulation of microstructures, introduction of functional building blocks, and enhancement of interfacial interactions, which not only improve the mechanical properties of layered polymer nanocomposites, but also endow them with functional applications, such as electromagnetic shielding, thermal conductivity and self-monitoring of structural integrity. Finally, we provide an outlook on the future directions and challenges of the structural design, performance optimization and application expansion of nacre-inspired layered polymer nanocomposites constructed by the ice templating technique. Fig. & Tab. | Reference | Related Articles | Metrics Review Chemical Modification and Delivery System of Small Interfering RNA Drugs★ Chen Li, Xiao Si, Jinbo Li, Yan Zhang Acta Chimica Sinica 2023, 81 (9): 1240-1254. DOI: 10.6023/A23040179 Published: 18 July 2023 Abstract (400) HTML (37) PDF (3406KB)(611) Knowledge map In the past decade, nucleic acid therapeutics have experienced rapid development, with RNA interference (RNAi) based technology emerging as a versatile tool widely used in the treatment of various diseases. Small interfering RNA (siRNA), as a sequence-specific gene silencing method, has provided an effective and specific means for studying gene function and developing new therapeutic strategies. Consequently, there has been significant interest in utilizing siRNA as a method to target specific gene functions in therapy. However, in order to make RNAi technology valuable and effective, it is crucial to chemically modify siRNA and develop efficient siRNA delivery strategies. These measures aim to improve the stability and cellular uptake capability of siRNA, enhance sequence specificity, and reduce non-specific gene silencing and biotoxicity. This review provides a concise introduction to the chemical modifications of siRNA aimed at enhancing its resistance to nucleases and stability. Additionally, the development of siRNA delivery systems, including lipid-based and polymer-based carrier systems, represents a significant research direction. These systems aim to improve the pharmacokinetics of siRNA, enhance intracellular delivery, and achieve tumor targeting. Finally, this review summarizes and discusses the technological bottlenecks and future trends in siRNA drug delivery, providing guidance for the further application of siRNA as a therapeutic strategy. Fig. & Tab. | Reference | Related Articles | Metrics Review Research Progress of Bis(terpyridine)-Ruthenium(II) Complexes★ Zhikai Li, Siqi Luo, Min Chen, Xiujun Yu, Xiaopeng Li Acta Chimica Sinica 2023, 81 (10): 1447-1461. DOI: 10.6023/A23050201 Published: 28 June 2023 Abstract (400) HTML (23) PDF (5349KB)(671) Knowledge map Over the past decades, thanks to the excellent directivity and stability of coordination bond between terpyridine and ruthenium ions, a large number of bis(terpyridine)-ruthenium(II) complexes have been constructed and reported through three synthetic strategies, i.e., direct coordination assembly, stepwise coordination assembly and post-assembly modification. Moreover, due to the unique photoelectric properties of bis(terpyridine)-ruthenium(II) complexes, these structures have shown great promise for applications in photothermal conversion, photovoltaic materials, electronic memory and anion exchange membranes. Therefore, this review summarizes the research progress of bis(terpyridine)-ruthenium(II) complexes with particular focus on small molecules, discrete supramolecules and polymers. Furthermore, current challenges and opportunities are briefly discussed. Fig. & Tab. | Reference | Related Articles | Metrics Review Poly-adenine-based DNA Probes and Their Applications in Biosensors★ Lanying Li, Qing Tao, Yanli Wen, Lele Wang, Ruiyan Guo, Gang Liu, Xiaolei Zuo Acta Chimica Sinica 2023, 81 (6): 681-690. DOI: 10.6023/A23040121 Published: 01 June 2023 Abstract (396) HTML (20) PDF (4491KB)(567) Knowledge map Compared to traditional thiolated DNA probes, poly-adenine-based DNA probes (polyA DNA probes) are free of special chemical modifications, and thus exhibit unique advantages of easy synthesis, low economic cost, and excellent stability. Using their intrinsic polyA fragments, polyA DNA probes are combined onto the gold surface to form a compact and ordered monolayer with both anchoring and recognition capabilities. As a result, polyA DNA probes have attracted numerous research interests in biosensing. In this review, we first presented the mechanism of interaction between polyA DNA probes and the gold surface and then reviewed the applications of the polyA DNA probes in the development of biosensors, including colorimetric biosensors, fluorescence biosensors, surface-enhanced Raman scattering (SERS) biosensors, and electrochemical biosensors. We concluded with a discussion of the opportunities and challenges for polyA DNA probes and expected this review to be informative for the development of biosensors in food safety, environmental monitoring, and biomedicine. Fig. & Tab. | Reference | Related Articles | Metrics Perspective Research Progress of Active Colloidal Motors and Their Application Perspective in Electromagnetic Wave Absorption★ Jing Zheng, Jinkun Liu, Chunyi Luo, Guochao Zeng, Guanglei Wu, Xu Hou Acta Chimica Sinica 2023, 81 (10): 1394-1401. DOI: 10.6023/A23040190 Published: 12 September 2023 Abstract (389) PDF (6198KB)(457) Knowledge map Active colloidal motors are micro- or nanoparticles that can move actively and perform complex tasks at the micro- or nanoscale. They have great potential for various applications, such as environmental remediation, biomedical applications and micro- and nanomanufacturing. The development and latest research progress of active colloidal motors are reviewed, their driving mechanisms in different environments are discussed, and the development of new colloidal motors and their applications in different fields are explored. Finally, the perspective on the possible application of active colloidal motors in the field of electromagnetic wave absorption, including the mechanism of action, possible preparation strategies for electromagnetic wave absorption, and their potential performance and new functional applications are presented. Reference | Related Articles | Metrics Article Novel Bipolar Orange Emissive Iridium(III) Complexes: Design, Synthesis, and Electroluminescence★ Peng Tao, Xiaokang Zheng, Guoliang Wang, Xinghao Sheng, He Jiang, Wentao Li, Jibiao Jin, Sui-Hung Wong, Yanqin Miao, Hua Wang, Wai-Yeung Wong Acta Chimica Sinica 2023, 81 (8): 891-897. DOI: 10.6023/A23040187 Published: 26 June 2023 Abstract (385) HTML (17) PDF (1141KB)(317) Knowledge map White organic light-emitting diodes (OLEDs) are promising candidates for novel solid-state lighting devices, and high-performance orange light-emitting materials are one of the key factors to realize high-performance complementary color white OLEDs. In this work, we designed a new bipolar cyclometalating ligand by incorporating carbazole moiety with hole-transport ability into 2-phenyl-4-methylquinoline with a large torsion angle. Based on this carbazole-bearing cyclometalating ligand, a pair of orange emissive iridium(III) complexes (Ir1 and Ir2) showing bipolar transport ability are prepared by selecting 2,2,6,6-tetramethylheptane-3,5-dione and picolinic acid as ancillary ligands. Two complexes and the corresponding cyclometalating ligand are well characterized by 1H and 13C nuclear magnetic resonance spectrometry, and mass spectrometry, and the new bipolar cyclometalating ligand and complex Ir1 are also confirmed by X-ray diffraction analysis. The single crystals of Ir1 crystallized in the orthorhombic space group P212121. Its unit cell parameters are α=β=γ=90°, a=1.271 nm, b=1.522 nm, c=3.161 nm. In O2-free toluene solution at room temperature, both complexes exhibit intense orange phosphorescence (587 nm for Ir1, 570 nm for Ir2) with high photoluminescent quantum yields of 69% and 74% and with short lifetimes of 1.50 and 1.62 μs. Most importantly, they not only show relatively broad full width at half maximum (FWHM) of 83 nm for Ir1 and 88 nm for Ir2 in their emission spectra but also possess bipolar transport ability, which will be beneficial to realize high-performance electroluminescence. Complex Ir2 is selected as the dopant to fabricate orange OLEDs. The as-prepared OLED realizes a broad orange emission at 569 nm with FWHM of 86 nm, maximum brightness of 4826 cd•m-2, external quantum efficiency (EQE) of 15%, current efficiency of 35.7 cd•A-1, and power efficiency of 23.4 lm•W-1. The results demonstrate that the new bipolar orange emissive iridium(III) complexes designed by incorporating carbazole moiety with hole-transport ability into the cyclometalating ligand with a large torsion angle will be the promising candidates for the future design of high-performance white organic light-emitting diodes. Fig. & Tab. | Reference | Supporting Info. | Related Articles | Metrics Perspective Application Progress of Emerging Janus Particles for Oil-Water Separation★ Duanda Wang, Xinyi Shen, Yongyang Song, Shutao Wang Acta Chimica Sinica 2023, 81 (9): 1187-1195. DOI: 10.6023/A23050204 Published: 04 July 2023 Abstract (379) HTML (24) PDF (2097KB)(336) Knowledge map Janus particles are micro-nano materials with anisotropic surface chemical properties, exhibiting unique advantages in emulsion stabilization, interfacial adsorption, and selective wetting. The high interfacial activity of Janus particles makes them widely used in oil-water separation research and shows broad application prospects in environmental protection and other fields. In this perspective, we summarize the research progress of emerging Janus particles in preparation, properties, and oil-water separation applications in recent years. We focus on discussing the influence of different preparation strategies and morphologies of Janus particles on their interfacial properties, summarize the mechanism of particle assembly and aggregation at interface, and introduce various Janus particles with reversible responsive properties. Finally, we prospect the challenges and future development directions of Janus particles in oil-water separation, such as green synthesis, large-scale preparation, in-depth mechanism research, and applications in aspects such as micro-oil droplet removal, crude oil treatment, and controllable responsive separation. Fig. & Tab. | Reference | Related Articles | Metrics Review Modular Bifunctional Organoboron-ammonium/phosphonium Catalysts: Design and Catalytic Performance★ Guan-Wen Yang, Guang-Peng Wu Acta Chimica Sinica 2023, 81 (11): 1551-1565. DOI: 10.6023/A23050206 Published: 21 July 2023 Abstract (376) HTML (23) PDF (6413KB)(716) Knowledge map Organoboron compounds are a class of non-metallic catalysts that have been extensively studied in recent years and have shown excellent applicability for ring-opening homopolymerization of epoxides and copolymerization of epoxides with other comonomers. However, the binary electrophile/nucleophile catalytic systems often have reduced activity or be deactivated due to the entropic disadvantage under dilute conditions, and it is also difficult to afford polymer materials with high molecular weight. This paper reviews the progress of bifunctional organoboron-quaternary ammonium/phosphonium salt catalytic systems containing both electrophilic and nucleophilic centers in one molecule that was designed by our group, focuses on the design concepts and principles of such bifunctional organoboron catalysts, compares the polymerization mechanisms between bifunctional and binary organoboron catalytic systems, and summarizes the use of bifunctional organoboron catalysts in the ring-opening polymerization of epoxides to prepare aliphatic polyethers, the copolymerization of epoxides and carbon dioxide/cyclic anhydride to prepare polycarbonates/polyesters. The future and trend of organoboron catalysts in polymer chemistry were prospected. Fig. & Tab. | Reference | Related Articles | Metrics Review Rare Earth Biological Manufacturing and High Value-added Material Application★ Yuewen Zhong, Xining Qian, Chao Ma, Kai Liu, Hongjie Zhang Acta Chimica Sinica 2023, 81 (11): 1624-1632. DOI: 10.6023/A23070323 Published: 16 October 2023 Abstract (373) HTML (26) PDF (8138KB)(525) Knowledge map Rare earth elements (REEs) are widely used in various frontier fields as critical raw materials for the development of modern industries and technologies. Due to the scattered distribution, the mining of rare earth elements is often accompanied by damage to the natural environment; similar chemical properties also make the separation of rare earth elements with high energy consumption and severe pollution. Through the construction of engineered rare earth microorganisms, biomining technology can be employed to address the challenges encountered in traditional processes. Moreover, establishing an engineered rare earth microbial synthesis platform enables the in situ synthesis of high value-added rare earth biomaterials, thereby facilitating clinical translational research and application in the field of rare earth biomaterials. The rational design of rare earth microorganisms, the synthesis of high value-added rare earth biomaterials, and their applications are discussed in this review. An outlook for future research and development in this field is presented. Fig. & Tab. | Reference | Related Articles | Metrics page Page 1 of 3 Total 89 records First page Prev page Next page Last page