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Science China Chemistry 2023年第12期66卷 3539-3545页

作者： Chengxi Zhang Yang Xi jingping qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghai 200237China

The highly diastereoselective dicarbofunctionalization of substituted olefins still remains a daunting challenge in synthetic ***,we report a Pd-catalyzed diastereoselective 1,1-diarylation of 1,1-diarylethylene with chelation group free to enable the modular synthesis of smart material candidates,1,1,2,2-tetraarylethanes(TAEs),which represent the first protocol by assembling four different aryl groups into ethane *** mechanistic experiments suggest that the crucial Pd–H species generated in situ do not disengage from the alkene intermediate during the reaction.

关键词： 1,1,2,2-tetraarylethane palladium cross-coupling reaction alkene multicomponent reactions

Nickel/quinim Enabled Asymmetric Carbamoyl-Acylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2023年第14期41卷 1673-1678页

作者： Xianqing Wu Haiyan Li Feng He jingping qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China

Transition metal-catalyzed difunctionalization of tethered alkene has emerged as a prevailing tool for the expedient construction of synthetically valuable cyclic ***,most efforts have been devoted to the reaction of styrene-type substrates due to their rigid scaffold and high *** respect to the difunctionalization of nonaromatic tethered olefin,especially the mono-substituted alkene,still remains largely ***,we disclose a nickel/quinim complex and TBADT-cocatalyzed asymmetric carbamoyl-acylation of unactivated alkene tethered on nonaromatic carbamoyl chlorides with diverse *** reaction exhibits broad substrate scope with good functional group tolerance,as well as high reaction efficiency and *** monosubstituted and 1,1-substituted alkenes can work well with either aliphatic or aromatic aldehydes under the current protocol,providing convenient access to an array of medicinally useful chiralγ-lactams derivatives bearing a convertible acyl *** reaction showcases more application possibilities of the chiral quinim ligand in the future asymmetric catalytic transformations.

关键词： Nickel quinim ligand Lactams Asymmetric catalysis Alkenes

Magnetostriction of Pseudobinary Compounds Pr_(0.15)Tb_xDy_(0.85-x)Fe_2(x=0 to 0.85)

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Journal of Materials Science & Technology 2000年第6期16卷 641-642页

作者： Yangxian LI jingping qu Chengchun TANG Guangheng WU Wenshan ZHAN Hebei University of Technology Tianjin 300130 China State Key Laboratory for Magnetism Institute of Physics CAS BeiJing 100080 China

The compound ingots of Pr0.15TbxDy0.85-xFe2 (x=0 to 0.85) were prepared by arc melting in a water Cu boat using arc furnace under a purified Ar atmosphere. Appropriate annealing (850℃, 100 h) can obtain single Laves phase compound. The magnetostriction for these systems will rise obviously when partially substituted Tb or Dy by Pr.

关键词： x=0 to 0.85 Fe x)Fe2 x Magnetostriction of Pseudobinary Compounds Pr Pro

Nickel-Catalyzed Regiodivergent Acylzincation of Styrenes with Organozincs and CO

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Chinese Journal of Chemistry 2024年第6期42卷 599-604页

作者： Chenglong Wang Ning Liu Xianqing Wu jingping qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China Dedicated to the Special Issue of C1 Chemistry.

Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C ***,the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction,which greatly increases the horizon of carbometallation ***,we report a nickel-catalyzed regiodivergent acylzincation of o-cyano cinnamate ester and o-cyano styrene,in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization *** protocol features mild conditions,broad substrate scope and excellent functional group tolerance,thus affording a diverse array of highly functionalized carbocyclic compounds.

关键词： Carbonylation Carbometallation Styrene Nickel Cyclization

Construction of a low-valent thiolate-bridged dicobalt platform and its reactivity toward hydrogen activation and evolution

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Chinese Chemical Letters 2022年第5期33卷 2477-2480页

作者： Tao Mei Dawei Yang Linan Su Baomin Wang jingping qu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China

Low-valence transition metallic complexes have drawn longstanding attention due to their high reactivity toward catalytic transformation of various small *** these known complexes,the low-valence metal centres are commonly stabilized by neutral bulky ligands with strong electron-donating ***,low-valence bimetallic complexes supported by anionic sulfur and cyclopentadienyl ligands are still difficult to obtain in high isolated ***,we report the synthesis and characteri-zation of two scarce thiolate-bridged Co^(I)Co^(II)and Co^(I)Co^(I)complexes bearing sterically demanding ligands through two stepwise one-electron reduction ***,the Co^(I)Co^(II)complex can facilely promote the homolytic cleavage of dihydrogen across the short Co−Co metallic bond to give a Co^(II)Co III dihydride bridged complex,which is capable of serving as a competent hydrogen atom transfer ***,the anionic Co^(I)Co^(I)complex can trigger a stepwise hydrogen generation cycle involving several isolated and structurally well-characterized intermediates.

关键词： Low-valence Thiolate-bridged Cobalt Homolytic H_(2)cleavage Hydride Hydrogen evolution

Synthesis,characterization and reactivity of thiolate-bridged cobalt-iron and ruthenium-iron complexes

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Chinese Chemical Letters 2022年第1期33卷 217-220页

作者： Chao Guo Linan Su Dawei Yang Baomin Wang jingping qu State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Centre for BiomanufacturingFrontiers Science Center for Materiobiology and Dynamic ChemistryEast China University of Science and TechnologyShanghai 200237China

Thiolate-bridged hetero-bimetallic complexes[Cp^(*)M(MeCN)N_(2)S_(2)FeCl][PF_(6)](2,M=Ru;3,M=Co,Cp^(*)=η^(5)-C_(5)Me_(5),N_(2)S_(2)=N,N'-dimethyl-3,6-diazanonane-1,8-dithiolate)were prepared by self-assembly of dimer[N_(2)S_(2)Fe]2 with mononuclear precursor[Cp^(*)Ru(MeCN)_(3)][PF_(6)]or[Cp^(*)Co(MeCN)_(3)][PF_(6)]_(2)in the presence of CHCl_(3)as a chloride *** 2 and 3 exhibit obviously different redox behaviors investigated by cyclic voltammetry and spin density distributions supported by DFT ***,iron-cobalt complex 3 possesses versatile reactivities that cannot be achieved for complex *** the presence of CoCp_(2),complex 3 can undergo one-electron reduction to generate a stable formally Co^(II)Fe^(II)complex[Cp^(*)CoN_(2)S_(2)FeCl](4).Besides,the terminal chloride on the iron center in 3 can be removed by dehalogenation agent AgPF_(6)or exchanged with azide to afford the corresponding complexes[Cp^(*)Co(MeCN)N_(2)S_(2)Fe(MeCN)][PF_(6)]_(2)(5)and[Cp^(*)Co(MeCN)N_(2)S_(2)Fe(N_(3))][PF_(6)](6).In addition,complexes 2,3 and 4 show distinct catalytic reactivity toward the disproportionation of hydrazine into *** results may be helpful to understand the vital role of the heterometal in some catalytic transformations promoted by heteromultinuclear complexes.

关键词： Metallic cooperativity Heterobinuclear complex Hydrazine disproportionation Metallothiolate ligand Metal-sulfur cluster

Electronic Structure of Thiolate-bridged Diiron Complexes and a Single-electron Oxidation Reaction＂ A Combination of Experimental and Computational Studies

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Chinese Journal of Chemistry 2016年第9期34卷 919-924页

作者： Si Chen Lun Luo Yang Li Dawei Yang jingping qu Yi Luo State Key Laboratory of Fine Chemicals School of Pharmaceutical Science and Technology Dalian University of Technology Dalian Liaoning 116024 China

Single-electron oxidation of a diiron-sulfur complex [Cpπ＊Fe（μ-bdt）FeCp^＊] （1, Cp^＊=η^5-C5Me5; bdt = benzene-1,2-dithiolate） to [Cp^＊Fe（μ-bdt）FeCp^＊]]^＋（2） has been experimentally conducted. The bdt ligand with redoxactive character has been computationally proposed to be a dianion （bdt62-） rather than previously proposed monoanion （bdt^-） radical in 1 though it has un-equidistant aromatic C-C bond lengths. The ground state of 1 is predicted to be two low-spin ferrous ions （SFe= 0） and 2 has a medium-spin ferric ion （SFe= 1/2） and a low-spin ferrous center （SFe=0）, and the oxidation of 1 to 2 is calculated to be a single-metal-based process. Both complexes have no significant antiferromagnetic coupling character.

关键词： density functional theory iron-sulfur cluster benzene-1,2-dithiolate non-innocent ligand single-electron oxidation

Palladium-catalyzed stereoselective trifluoromethylated allylic alkylation of 3-substituted oxindoles

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Organic Chemistry Frontiers 2022年第3期9卷 810-815页

作者： Dong Li Shuaibo Zhang Bangzhong Wang Wuding Sun Jinfeng Zhao jingping qu Yuhan Zhou State Key Laboratory of Fine Chemicals Department of Pharmaceutical SciencesSchool of Chemical EngineeringDalian University of Technology2 Linggong RoadDalian 116024China State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of Technology2 Linggong RoadDalian 116024China

An efficient catalytic methodology for trifluoromethylated allylic alkylation of 3-substituted oxindoles usingα-(trifluoromethyl)alkenyl acetates as the trifluoromethyl-containing allylic alkylation partner is *** reaction proceeds smoothly with the incorporation of Pd(OAc)_(2) and(R)-BINAP,affording various functionalized trifluoromethyl-containing 3,3’-disubstituted oxindoles with high yields and good enantioselectivities.

关键词： substituted alkylation indole

Influence of stresses on martensitic transformation in ferromagnetic shape memory Ni_(50)Mn_(19)Fe_6Ga_(25) ribbons

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Science China(Technological Sciences) 2004年第6期47卷 710-715页

作者： MENG Fanbin LI Yangxian LIU Heyan qu jingping LIU Zhuhong CHEN Jinglian WU Guangheng School of Mechanical Science and Engineering Hebei University of TechnologyTianjin 300130China State Key Laboratory for Magnetism Institute of PhysicsChinese Academy of SciencesBeijing 100080China

The influence of stresses on martensitic transformation in Ni50Mn19Fe6Ga25 melt-spun ribbons was studied. X-ray diffraction examination shows that the ribbon has a pure cubic L21 phase at room temperature and that the ribbon surface exhibits [100] preferentially oriented texture, while the [110] axis is about 45° tilted from the normal of the ribbon. By calculating the d spacing at different angles with the length direction of the ribbon, the tension was observed. It was found that the direction of the stress was along [010] direction of the oriented textured grains. During cooling, there is no obvious structural transition observed in as-spun ribbons. However, when the ribbons were annealed at 900 K for 24 h, the tension along [010] direction disappeared and the structural transition from cubic to tetragonal occurred obviously during cooling. It indicates that it is the tension along [010] direction to suppress the martensitic transformation in the as-spun ribbons.

关键词： stress martensitic transformation ferromagnetic shape memory alloy

Enantioselective Synthesis ofα-Alkenylatedγ-Lactam Enabled by Ni-Catalyzed 1,4-Arylcarbamoylation of 1,3-Dienes

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CCS Chemistry 2023年第2期5卷 341-349页

作者： Feng He Liting Hou Xianqing Wu Haojie Ding jingping qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237

The facile construction of chiral quaternaryα-alkenylated pyrrolidinones is a long-term challenge in organic *** asymmetric difunctionalization of 1,3-dienes represents the most compelling tool for assembling alkenylated compounds by regioselective 1,2-or 1,***,the manipulation of unactivated 1,3-dienes to forge the quarternary stereogenic center still remains largely ***,we disclose a nickelcatalyzed asymmetric 1,4-arylcarbamoylation of unactivated 1,3-dienes tethered on carbamoyl fluoride with readily available arylboronic acids,providing rapid access to the enantioenrichedα-alkenylated pyrrolidinones bearing the quaternary stereogenic center in high yields with broad functional group ***,this chiral ligand-controlled asymmetric transformation overcomes the intrinsic substrate control with a preexisting chiral center.

关键词： lactam nickel 1 3-diene enantioselective dicarbofunctionalization quaternary stereogenic center