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Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-sheng Nong Hao-Fan Qian Ying-Chun Chen pu-sheng wang Liu-Zhu Gong Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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Pd-Catalyzed Asymmetric Allylic C—H Functionalization

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Chinese Journal of Chemistry 2023年第15期41卷 1841-1848页

作者： pu-sheng wang Liu-Zhu Gong Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China Center for Excellence in Molecular Synthesis of CAS University of Science and Technology of ChinaHefeiAnhui 230026China

Comprehensive Summary Pd-catalyzed asymmetric allylic C—H functionalization has emerged as a powerful tool to access chiral,densely functionalized molecules from easily accessible alkenes,enabling the increase of the step-or atom-economy by minimizing functional group manipulations for preparing allylating *** to the inadequacy of stereoselection strategies,the asymmetric allylic C—H functionalization is still in the early *** this essay,we will describe our journey to identification of asymmetric catalytic systems,mechanism of allylic C—H activation,control of stereo-and regioselectivity,and applications in asymmetric synthesis.

关键词： C-H activation Asymmetric catalysis Allylation Palladium Allylic compounds Regioselectivity Alkenes

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Palladium-catalyzed asymmetric allylic C–H alkylation of 1,4-dienes and glycine Schiff bases

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Science China Chemistry 2020年第4期63卷 454-459页

作者： Tian-Ci wang pu-sheng wang Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of Chinese Academy of Sciences Hefei 230026China

A highly regio-and enantioselective allylic C–H alkylation of 1,4-dienes with glycine Schiff bases has been established by chiral palladium-phosphoramidite catalysis. This reaction can proceed under mild conditions and tolerate a wide scope of 1,4-dienes,delivering structurally diverse chiral β-branched α-amino acid surrogates in moderate to high yields and with high levels of regio-, Z/E-, diastereo-and enantioselectivities.

关键词： asymmetric catalysis palladium allylic C–H alkylation 1,4-diene glycine Schiff base

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Access to chiral homoallylic vicinal diols from carbonyl allylation of aldehydes with allyl ethers via palladium-catalyzed allylic C-H borylation

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Science China Chemistry 2022年第2期65卷 298-303页

作者： Tian-Ci wang pu-sheng wang Dian-Feng Chen Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of CAS Hefei 230026China

Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.

关键词： asymmetric catalysis palladium allylic C–H borylation allyl ethers chiral phosphoric acid aldehydes

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Platinum-Catalyzed Allylic C-H Alkylation with Malononitriles

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CCS Chemistry 2022年第4期4卷 1366-1375页

作者： Lian-Feng Fan Pei-Pei Xie pu-sheng wang Xin Hong Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei 230026 Department of Chemistry Zhejiang UniversityHangzhou 310027 Center for Excellence in Molecular Synthesis of Chinese Academy of Sciences Hefei 230026

The direct functionalization of allylic C-H bonds is distinguished by enabling rapid assembly of structural complexity from simple *** Pd-catalyzed allylic C-H functionalization has been extensively studied,the discovery of new catalytic systems remains fairly ***,we disclose a Pt-catalyzed allylic C-H alkylation of a wide range of α-alkenes by using phosphoramidites as ligands and malononitriles as alkylating ***,the combination of chiral ureacatalyzed Michael addition and Pt-catalyzed allylic C-H alkylation can serve as an efficient protocol to access chiral tetrahydropyran with high levels of diastereo-and *** studies suggest that the Pt-catalyzed allylic C-H activation proceeds through a concerted proton and two-electron transfer process,which is analogous to transition state geometries of Pd catalysis.

关键词： platinum catalysis phosphoramidite C-H activation allylic alkylation concerted proton and two-electron transfer

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Combined biochar and wheat-derived endophytic bacteria reduces cadmium uptake in wheat grains in a metal-polluted soil

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Journal of Environmental Sciences 2025年第1期147卷 165-178页

作者： Zhihui Xiong Yaping wang Linyan He Qi sheng Xiafang sheng College of Life Sciences Key Laboratory of Agricultural and Environmental MicrobiologyMinistry of AgricultureNanjing Agricultural UniversityNanjing 210095China

In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic ***,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 *** BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR *** with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd *** the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation *** findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.

关键词： Cd-immobilizing endophytic bacteria Cd-contaminated soil Biochar+endophytic bacteria Grain Cd uptake Specific biomarkers

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Receiver-device-independent quantum secure direct communication

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Cheng Liu Cheng Zhang Shi-pu Gu Xing-Fu wang Lan Zhou Yu-Bo sheng College of Science Nanjing University of Posts and Telecommunications College of Electronic and Optical Engineering College of Flexible Electronics (Future Technology)Nanjing University of Posts and Telecommunications

Quantum secure direct communication (QSDC) enables the sender to directly transmit secure messages to the receiver via a quantum channel without the need for ***-independent (DI) and measurement-device-independent (MDI) QSDC protocols theoretically enhance the practical security of ***,DI QSDC requires extremely high global detection efficiency and has a limited secure communication *** DI and MDI QSDC protocols depend on high-quality *** entanglement sources,which generate entangled photon pairs with low efficiency,significantly reduce their practical communication *** this paper,we propose a single-photon-based receiver-device-independent (RDI) QSDC *** protocol relies solely on the practical single-photon source,which is nearly on-demand with current technology,and treats all receiving devices on both ends of the communication as“black boxes”.The security of the message is ensured only through the observed *** also develop a numerical method to simulate the protocol’s performance under practical noisy communication *** RDI QSDC protocol provides the same security level as MDI *** to DI and MDI QSDC,RDI QSDC has several ***,it uses single-photon sources and single-photon measurements,which allow it to achieve practical communication efficiency approximately 3415 times greater than that of DI QSDC,while being easier to *** entire protocol is feasible with current ***,it offers higher robustness to photon loss and better noise tolerance than DI QSDC,enabling a secure communication distance approximately 26 times greater than that of DI *** on these advantages,the RDI QSDC protocol presents a promising approach for achieving highly secure and efficient QSDC in the near future.

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Chiral Anion Strategy For Asymmetry Allylic Alkylation

Chiral Anion Strategy For Asymmetry Allylic Alkylation

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手性中国2014学术研讨会

作者： pu-sheng wang Xiao-Le Zhou Hua-Chen Lin Liu-Zhu Gong Department of Chemistry University of Science and Technology of China

＜正＞Since the seminal reports by Tsuji and Trost on the palladium-catalyzed allylic alkylation,[1]this transformation has been accepted as one of the most significant carbon-carbon or carbon-heteroatom bond forming *** particular,the asymmetric version（AAA）has been a long term hot project receiving worldwide attention.[2]This reaction has eventually prompted the explosive development of chiral hgands and also led to the emergence of synthetically

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Controlling segregation and hardenability of gear steel based on as-cast structure

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Journal of Iron and Steel Research International 2025年第1期32卷 144-158页

作者： Hai-jie wang Ze Zhang Peng Lan Gang Chen pu wang Chuan-hui Jiang Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Weifang Iron and Steel Group Co. Ltd.Weifang 261000ShandongChina

Hardenability significantly impacts the distortion of gear during heat treatment,correlated to the uniformity of solute distribution in steel *** experimental analysis was conducted on the macrostructure,solute distribution,dendrite structure,and rod hardenability of 20CrMnTiH gear steel in continuously cast blooms and hot roller *** evaluation approach by the standards for the hardenability of gear steel rods and the corresponding blooms was analyzed,and the inheritance mechanism from solidification segregation to hardenability fluctuation of gear steel was *** results indicate that semi-macroscopic spot segregation located in the equiaxed zone exhibits larger size,higher solute enrichment,and worse solute homogeneity,leading to significant solute fluctuations in the blooms and hardenability fluctuation in the *** increasing the liquid steel superheat from 35 to 40℃,reducing the mold electromagnetic stirring from 300 to 100 A,and implementing the soft reduction(SR)of 7 mm at the solidification end,the equiaxed ratio of the strand decreased from 26.42%to 6.69%.Consequently,the solute fluctuation range and standard deviation decrease significantly in the transverse section,while the maximum segregation ratio,average fluctuation range,and average standard deviation of solutes C,Cr,and Mn in the spot segregation decrease at the same *** the meanwhile,the equiaxed ratio of the rod decreased from 24.89%to 4.09%,and the structure of the hardenability detection zone was transformed from equiaxed crystals to columnar ***,the solute fluctuation range and standard deviation in the transverse section decreased,while the homogeneity in spot segregation was also *** hardness difference of A and B surfaces at J9 and J15 positions was smaller than 2 HRC,meeting the qualification standard for hardenability.

关键词： Gear steel Continuous casting Solute distribution Dendritic structure Hardenability

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Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng Xu sheng Pang Liangwei Cong Guoyu Qian Dong wang Laishi Li Yusheng Wu Zhi wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis

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