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Recent advances in post-chiroptical manipulation of supramolecular aggregates assembled with molecular modules

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Science China chemistry 2024年第9期67卷 2842-2863页

作者： Yanling Shen Wanhua Wu Zhipeng Yu Cheng Yang Key Laboratory of green chemistry&Technology of Ministry of Education College of Chemistry InstitutionSichuan UniversityChengdu 610064China

Recently,various supramolecular assembly systems have been identified where the pre-existing chiral supramolecular structure can be manipulated through environmental adjustments,such as temperature,solvent,and *** changes result in diverse microscopic morphologies during the assembly process and induce chiroptical variations,particularly in circular dichroism(CD)and circularly polarized luminescence(CPL)*** chiroptical properties serve as direct indicators of the chiral supramolecular structure and hold promise for applications in sensing,molecular recognition,asymmetric synthesis,and material *** review focuses on research published in the last five years,highlighting instances where assembled structures aggregated by small organic molecular modules demonstrate in-situ chiroptical changes through external condition *** categorizes and discusses different modes of regulation,aiming to offer insights and guidelines for exploring dynamic changes in assembly processes and designing in-situ adjustable structures of assembly modules.

关键词： supramolecular assemblies post-chiroptical manipulation in-situ structural changes

Selective synthesis of the B_(11)H_(14)^(-) and B_(12)H_(12)^(2-) borane derivatives and the general mechanisms of the B-H bond condensation

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Science China chemistry 2024年第3期67卷 876-881页

作者： Yi Jing Xinghua Wang Hui Han Xin-Ran Liu Xing-Chao Yu Xi-Meng Chen Donghui Wei Lai-Sheng Wang Xuenian Chen College of chemistry Green Catalysis CenterZhengzhou UniversityZhengzhou 450001China School of chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy MaterialsHenan Normal UniversityXinxiang 453007China department of chemistry Brown UniversityProvidenceRI 02912USA

Polyhedral boranes are a class of well-known boron molecular clusters with unique physical and chemical properties,and great efforts have been made in the past decades to find more effective synthetic ***,the established synthetic methods suffer from low efficiency and low selectivity because the mechanism of the B-H bond condensation reaction,critical for the synthesis of the polyhedral boranes,is not well *** we report highly selective and efficient synthetic methods of the salts of the tetradecahydridoundecaborate(1-)(B_(11)H^(-)_(14)) and dodecahydrido-dodecaborates(2-)(B_(12)H_(12)^(2-)) anions by employing commercially available and inexpensive starting *** theoretical and experimental investigations are carried out to elucidate the reaction *** have found that the nature of the B-H bond condensation is the dihydrogen bonding interaction in which the positively charged hydrogens(bridged hydrogens) play a crucial *** current study has not only led to more effective and selective synthetic methods for B_(11)H^(-)_(14) and B_(12)H_(12)^(2-) but also unveiled the nature of the B-H bond condensation and the general formation mechanisms of polyhedral *** finding will facilitate the development of more effective synthetic methods for polyhedral boranes and spur their wide application.

关键词： Boranes polyhedral boranes dihydrogen bond nucleophilicity

Sustainable electrosynthesis: Enantioselective electrochemical Rh(Ⅲ)/chiral carboxylic acid-catalyzed oxidative C–H cyclization coupled with hydrogen evolution reaction

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Chinese Chemical Letters 2024年第9期35卷 1-3页

作者： Xinghui Yao Zhouyu Wang Da-Gang Yu department of chemistry Xihua UniversityChengdu 610039China Key Laboratory of green chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China

Chiral compounds play a crucial role in the development of pharmaceuticals,pesticides,fragrances,and materials due to their unique stereochemical *** catalysis,which employs chiral catalysts to favor the production of one enantiomer over its mirror image,has emerged as a pivotal technique in the synthesis of chiral compounds[1].However,traditional asymmetric methods sometimes rely on environmentally harmful reducing or oxidizing agents,presenting a considerable challenge in the pursuit of green chemistry.

关键词： chiral oxidative catalyzed

Access to Enantioenriched Allylic Alcohols via Peptide-Mimic Phosphonium Salt-Catalyzed Asymmetric Aerobic Hydroxylation

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Chinese Journal of chemistry 2024年第17期42卷 2017-2022页

作者： Jixing Che Siqiang Fang Zanjiao Liu Jiaja He Jia-Yan Zheng Fan Wang Tianli Wang Key Laboratory of green chemistry&Technology of Ministry of Education College of ChemistrySichuan University29 Wangjiang RoadChengduSichuan610064China department of chemistry National University of SingaporeScience Drive 3Singapore 117543Singapore

The development of catalytic asymmetric methods that enable access to value-added functionalities or structures,exemplified by allylic alcohols,is a highly interesting yet challenging topic from both academic and industrial ***,before recent advances in chemical catalysis,there were scarce protocols toward constructing enantioenriched tertiary allylic alcohol *** this context,peptide-mimic phosphonium salts were found to be highly efficient in catalytic asymmetricα-hydroxylation ofα,β-unsaturated and/orβ,Y-unsaturated compounds with satisfactory regio-and stereochemical outcomes(up to 97%yield and 95%ee).This methodology tolerates a broad array of substrates and thus provides an expeditious and unified platform for the assembly of enantioenriched tertiary allylic alcohols by avoiding the use of additional reductants and expensive metal ***,the power of this protocol is enlarged by simple conditions and the use of air as a source of hydroxyl functionality.

关键词： Asymmetric catalysis Peptide-mimic phosphonium salts Aerobic hydroxylation Enantioenrichedα-allylic alcohols lon pairs Oxygen Ketones

Synergies from off-gas analysis and mass balances for wastewater treatment--Some personal reflections on our experiences

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Environmental Science and Ecotechnology 2024年第5期21卷 413-417页

作者： Eveline I.P.Volcke BioCo Research Group Department of Green Chemistry and TechnologyGhent UniversityCoupure Links 6539000GentBelgium

Looking back at over a decade of research by herself and her group,the author advocates the added value of gas phase measurements and the application of mass balances,as well as the synergetic benefits obtained when combining *** increased application of off-gas measurements for greenhouse gas emission monitoring offers a great opportunity to look at other components in the gas phase,particularly *** balances should not be strictly reserved for modellers but also prove useful while conducting lab experiments and studying full-scale measurement *** off-gas measurements with mass balances may serve not only to quantify greenhouse gas emission factors and aeration efficiency but also to follow dynamic concentration profiles of dissolved components without dedicated sensors and/or to calculate other unmeasured ***-balance-based data reconciliation allows for obtaining reliable and accurate data,and even more when combined with off-gas analysis.

关键词： Wastewater treatment greenhouse gas emissions Mass balances Off-gas analysis Monitoring Data reconciliation

MOF‐derived 1D/3D N‐doped porous carbon for spatially confined electrochemical CO2 reduction to adjustable syngas

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Carbon Energy 2024年第8期6卷 1-13页

作者： Wei Zhang Hui Li Daming Feng Chenglin Wu Chenghua Sun Baohua Jia Xue Liu Tianyi Ma Key Laboratory for green Synthesis and Preparative chemistry of Advanced Materials Institute of Clean Energy ChemistryCollege of ChemistryLiaoning UniversityShenyangLiaoningChina School of Science RMIT UniversityMelbourneVictoriaAustralia School of Pharmaceutical and Chemical Engineering Taizhou UniversityTaizhouZhejiangChina department of chemistry and Biotechnology Swinburne University of TechnologyHawthornVictoriaAustralia

Electrochemical reduction of CO_(2)to syngas(CO and H_(2))offers an efficient way to mitigate carbon emissions and store intermittent renewable energy in ***,the hierarchical one‐dimensional/three‐dimensional nitrogen‐doped porous carbon(1D/3D NPC)is prepared by carbonizing the composite of Zn‐MOF‐74 crystals in situ grown on a commercial melamine sponge(MS),for electrochemical CO_(2)reduction reaction(CO_(2)RR).The 1D/3D NPC exhibits a high CO/H_(2)ratio(5.06)and CO yield(31 mmol g^(−1)h^(−1))at−0.55 V,which are 13.7 times and 21.4 times those of 1D porous carbon(derived from Zn‐MOF‐74)and N‐doped carbon(carbonized by MS),*** is attributed to the unique spatial environment of 1D/3D NPC,which increases the adsorption capacity of CO_(2)and promotes electron transfer from the 3D N‐doped carbon framework to 1D carbon,improving the reaction kinetics of CO_(2)*** results and charge density difference plots indicate that the active site of CO_(2)RR is the positively charged carbon atom adjacent to graphitic N on 1D carbon and the active site of HER is the pyridinic N on 1D *** presence of pyridinic N and pyrrolic N reduces the number of electron transfer,decreasing the reaction kinetics and the activity of CO_(2)*** CO/H_(2)ratio is related to the distribution of N species and the specific surface area,which are determined by the degree of spatial confinement *** CO/H_(2)ratios can be regulated by adjusting the carbonization temperature to adjust the degree of spatial confinement *** the low cost of feedstock and easy strategy,1D/3D NPC catalysts have great potential for industrial application.

关键词： electrochemical CO_(2)reduction reaction melamine sponge metal‐organic frameworks porous carbon syngas

Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-Xiu Shi Yi-Ming Ou Hua-Jie Jiang Yi-Jun Fang Qi-Ming Wang Quan Gao Jie Yu department of Applied chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

Copper/Photoredox-Catalyzed Regioselective 1,4-Addition to 1,3-Enynes: A Convenient Access to Perfluoroalkylated Allenes

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Chinese Journal of chemistry 2024年第17期42卷 2023-2028页

作者： Ya Chen Quanyuan Wang Keyi Peng Lilei Cheng Ziyi She Guo-Jun Deng Key Laboratory for green Organic Synthesis and Application of Hunan Province Key Laboratory of EnvironmentallyFriendly Chemistry andApplication of Ministryof EducationCollege of ChemistryXiangtan UniversityXiangtanHunan 411105China department School of chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

A general and broadly applicable copper and photoredox dual-catalyzed multicomponent 1,4-perfluoroalkylcyanation of 1,3-enynes has been *** protocol enjoys success with high regioselectivity,mild reaction conditions,and excellent functional-group tolerance,allowing the facile synthesis of structurally diverse perfluoroalkylated allenes from readily available fluoroalkyl halides,1,3-enynes and TMscN in a one-pot manner.A reasonable mechanism has been proposed according to a series of control experiments.

关键词： Fluorinated allenes 1 3-Enynes Photoredox Fluoroalkylation Multicomponent reactions Difunctionalization Radicals Regioselectivity

Carbene-catalyzed enantioselective seleno-Michael addition as access to antimicrobial active Se-containing heterocycles

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Science China chemistry 2024年第7期67卷 2199-2205页

作者： Hongyan Long Sha Zhao Chunyan Jian Xiuli Wu Fengfei Lu Minghong Liao Fengrui Che Xingxing Wu Yonggui Robin Chi State Key Laboratory of green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore

Organoseleniums exhibit a diverse set of biological activities that are pivotal for drug discovery and are widely explored in synthetic chemistry and material *** many transformations have been developed for non-enantioselective C–Se bond formations,the catalyst-controlled stereoselective preparation of chiral organoseleniums continues to be of considerable *** particular,there are limited studies on the enantioselective seleno-Michael addition reactions to access chiral selenium functional ***,we disclose a carbene-catalyzed highly enantioselective nucleophilic C–Se bond construction through formal[3+3]annulations between selenocarboxamides and bromoenals,affording seleno-thiazinone products with good yields and excellent *** choice of a weak inorganic base was pivotal to suppressing the unproductive racemization and decomposition of the selenium ***,the catalytically generated chiral selenium-containing heterocyclic products feature remarkable antimicrobial activities that could serve as promising lead scaffolds for further agrochemical development.

关键词： seleno-Michael addition organocatalysis N-heterocyclic carbene seleno-heterocycles antimicrobial activity