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Chinese Journal of Chemistry 2024年第7期42卷 705-710页

作者： Juan Wang Qing-Xian Xie Xiang Li Chang-Bin Yu Yong-Gui Zhou School of Chemistry Dalian University of Technology2 Linggong RoadDalianLiaoning 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China

The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric catalysis.Among them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framework and has been utilized as an important toolbox due to their structural stability.Herein,we design and synthesize[2.2]paracyclophane-derived oxazole-pyrimidine ligands(abberviated as PYMCOX).These N,N-ligands with stable properties,rigid structure and large steric hindrance performed successfully in nickel-catalyzed asymmetric 1,2-reduction ofα,β-unsaturated ketones,affording the chiral allylic alcohols with up to 99%yield and 99%ee.Meanwhile,this reduction reaction could be conducted on gram-scale without loss of activity and enantioselectivity,and the chiral ligand could be conveniently recovered with high yield.

关键词： Oxazole-pyrimidine ligands Planar chirality Nickel hydroboration Asymmetric synthesis

A Uranium(Ⅳ) Alkyl Complex: Synthesis and Catalytic Property in Carbonyl hydroboration

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Chinese Journal of Chemistry 2022年第17期40卷 2047-2053页

作者： Xiong Sun Xingxing Gong Zhuoyi Xie Congqing Zhu State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210093 China

The strong oxophilicity of actinide complexes prevents their applications in the transformation of oxygen-containing substrates.Herein,we report the use of a uranium(Ⅳ)alkyl complex as a catalyst for the hydroboration of carbonyl compounds.This reaction has good functional group tolerance and chemo-selectivity under mild conditions.This study represents the rare example of catalytic reaction promoted by a uranium alkyl complex and highlights the potential of uranium complexes in synthetic chemistry.

关键词： Actinides hydroboration Uranium Uraniumcatalyst Triamidoamines

Markovnikov-Selective hydroboration of Aryl Alkenes Enabled by a Simple Nickel Salt

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Chinese Journal of Chemistry 2022年第18期40卷 2203-2211页

作者： Tianfen Liu Chuhan Li Jiahui Bai Panke Zhang Yinlong Guo Xiaoming Wang Green Catalysis Center College of ChemistryZhengzhou University100 Science AvenueHigh-Tech DistrictZhengzhouHenan450001 China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang310024 China

The sustainable development of synthetic reactions catalyzed by earth-abundant metals is one of the principal goals in homogeneous catalysis.However,so far most of the protocols are still plagued by sophisticated ligands,hazardous activators,high catalyst loading(1—10 mol%)and/or multistep synthesis of the metal complexes in the process development.Consequently,the development of earth-abundant metal catalysts with high activity from commercially available metal salts is highly desirable for practical utilization of base metal catalyzed synthetic methodology.Herein,we report the catalyst generated in situ from a mixture of catalytic amounts of Ni(acac)_(2)(as low as 0.005 mol%)and CsF,which is found highly active for Markovnikov-selective hydroboration of vinylarenes,including 1,1-disubstituted vinylarenes and internal olefins,affording a wide range of secondary and tertiary alkyl boronates in excellent yields.Mechanistic experiments indicate that the key to the success of this catalysis is the use of CsF,which in combination with pinacolborane acts as an effective activator for Ni(acac)_(2),probably generating metastable Ni nanoparticles in situ that demonstrate high activity in the catalytic hydroboration(TON up to 18800).

关键词： Nickel salt hydroboration Earth-abundant metal catalysis Nanoparticles

Nickel-catalyzed cooperative B-H bond activation for hydroboration of N–heteroarenes, ketones and imines

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Chinese Chemical Letters 2023年第10期34卷 135-139页

作者： Zhuohao Zhao Jianguo Liu Chen-Ho Tung Wenguang Wang School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100China College of Chemistry Beijing Normal UniversityBeijing 100875China

We report two air-stable nickel(II) half-sandwich complexes,Cp*Ni(1,2-Cy_(2)PC_(6)H_(4)O)(1) and Cp*Ni(1,2-Ph_(2)PC_(6)H4NH)(2),for cooperative B-H bond activation and their applications in catalytic hydroboration of unsaturated organic compounds.Both 1 and 2 react with HBpin by adding the B-H bond across the Ni-X bond (X=O or N),giving rise to the 18-electron Ni(II)-H active species,[H1(Bpin)]and[H_(2)(Bpin)].Subtle tuning of the Ni-X pair and the supporting ancillary phosphine have a significant effect on the reactivity and catalytic performance of Cp*Ni(1,2-R_(2)PC_(6)H_(4)X).Unlike[H_(2)(Bpin)],the activation of HBpin in[H1(Bpin)]is reversible,which enables the Ni-O complex to be an effective cooperative catalyst in the hydroboration of N-heteroarenes,and as well as ketones and imines.

关键词： Nickel complex Metal-ligand cooperation B-H activation hydroboration Metal hydride

Ligand controlled cobalt catalyzed regiodivergent 1,2-hydroboration of 1,3-dienes

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Science China Chemistry 2019年第3期62卷 336-340页

作者： Sihan Peng Ji Yang Guixia Liu Zheng Huang State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry School of Physical Science and Technology Shanghai Tech University

Regiodivergent 1,2-hydroboration of 1,3-dienes with pinacolborane has been accomplished by well-defined cobalt complexes of different bidentate ligands. The iminopyridine-cobalt system is selective for Markovnikov 1,2-hydroboration to form allylboronates, while the FOXAP-cobalt(FOXAP=(S)-1-(diphenylphosphino)-2-[(S)-4-isopropyloxazolin-2-yl]ferrocene) catalyst effects the complementary anti-Markonikv 1,2-hydroboration to afford homoallyboronates with high regioselectivity.

关键词： cobalt dienes hydroboration regiodivergent

Copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids under ligand-free or both ligand-and base-free conditions

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Chinese Chemical Letters 2016年第4期27卷 571-574页

作者： Ying-Wei Zhao Qiang Feng Qiu-Ling Song Institute of Next Generation Matter Transformation College of Chemical Engineering Huaqiao University

An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis（pinacolato）diboron was developed, affording b-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.

关键词： Decarboxylation hydroboration Ligand-free Base-free Copper-catalysis

B(C_(6)F_(5))_(3)-Catalyzed hydroboration of Alkenes with N-Heterocyclic Carbene Boranes via B-H Bond Activation

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Chinese Journal of Chemistry 2021年第4期39卷 918-926页

作者： Qiaotian Wang Wei Meng Xiangqing Feng Haifeng Du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing100049 China

Main observation and conclusion In this work,a novel mode for the activation of N-heterocyclic carbene boranes(NHC-boranes)was developed by generating the highly reactive zwitterion species through hydride abstraction with Lewis acid B(C_(6)F_(5))_(3) in an frustrated Lewis pairs manner.A broad range of alkenes including stilbenes,β-methylstyrenes,styrenes,and alkyl-alkenes were suitable substrates for the B(C_(6)F_(5))_(3)-catalyzed hydroboration to furnish the desired products in good to high yields.Significantly,excellent regioselectivities were obtained in some cases.Mechanistic studies indicate that the B-H bond cleavage is likely involved in the rate-determining step.In addition,an electrophilic addition of NHC-borenium cation to alkenes and the subsequent formation of carbocation are also postulated.The current work provides a promising method for the activation of stable borane adducts,which might lead to some interesting transformations in the future.

关键词： Frustrated Lewis pairs hydroboration B-H bond activation Boranes Alkenes

Et2Zn-promoted β-trans-selective hydroboration of ynamide

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Chinese Chemical Letters 2020年第6期31卷 1564-1567页

作者： Kefeng Wang Zixi Zhuang Huihui Ti Peishan Wu Xin Zhao Honggen Wang Key Laboratory of Molecular Target&Clinical Pharmacology State Key Laboratory of Respiratory DiseaseSchool of Pharmaceutical Sciences&The Fifth Affiliated HospitalGuangzhou Medical UniversityGuangzhou 511436China Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China Guangdong Institute of Analysis(China National Analytical Center Guangzhou)Guangzhou 510070China

The trans-hydroboration of alkyne represents a challenging task in organic synthesis.Reported herein is an Et2 Zn promotedβ-trans hydroboration of ynamides by using N-heterocyclic carbene(NHC)-ligated borane as boryl source.The reaction leads to a stereoselective construction of enamides bearing a valuable boryl substituent.Both aromatic and aliphatic ynamides were applicable to the reaction.Synthetic transformation of the C-B bond in the product via Suzuki-Miyaura coupling provides a simple and stereospecific route to multi-substituted enamides.Mechanistic studies were conducted and the possible mechanism was discussed.

关键词： hydroboration Ynamide NHC-borane Et2Zn Enamid

Synthesis of difluoromethylated benzylborons via rhodium(Ⅰ)-catalyzed fluorine-retainable hydroboration of gem-difluoroalkenes

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Chinese Chemical Letters 2021年第1期32卷 417-420页

作者： Yuanhong Cai Donghang Tan Qiqi Zhang Wenxin Lv Qingjiang Li Honggen Wang Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen University.Guangzhou 510006China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal UniversityGuilin 541004China

The synthesis of bo rylated orga nofluorines is of great interest due to their potential values as synthons in modular construction of fluorine-containing molecules.Reported herein is a rhodium-catalyzed hydrobo ration of arylgem-difluoroalkenes leading to a series of α-difluoromethylated benzylborons.The use of cationic rhodium catalyst and a biphosphine ligand with large bite angle was crucial for reactivity by offering good regioselectivity and diminishing the undesired β-F elimination.Preliminary derivatizations of the products were conducted to showcase the utility of this protocol.

关键词： Rhodium hydroboration Difluoromethy gem-Difluoroalkene β-F elimination

Polyoxometalate-loaded Nanocellulose Sponge as a Novel Catalyst for the Regioselective hydroboration of Phenylacetylene

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Paper And Biomaterials 2019年第2期4卷 1-9页

作者： GuoQing Yang CongCong Zhang BiJia Wang ZhiPing Mao Hong Xu Yi Zhong XueLing Feng XiaoFeng Sui Key Lab of Science and Technology of Eco-textile Ministry of EducationCollege of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai201620China Innovation Center for Textile Science and Technology of DHU Donghua UniversityShanghai201620China

In this work,an amino-modified cellulose nanofiber sponge was prepared and used as a support for polyoxometalate(POM)catalysts with a high loading efficiency.Fourier transform infrared spectroscopy,thermogravimetric analysis,and energy-dispersive X-ray spectroscopy revealed that an Anderson-type POM,(NH4)4[CuMo6O18(OH)6]·5H2O was successfully immobilized on the sponge based on electrostatic interactions.Morphological analysis indicated that the POM-loaded sponge retained its porous structure and that the POM was homogeneously distributed on the sponge walls.The POM-loaded sponge exhibited excellent mechanical properties by recovering 79.9%of its original thickness following a 60%compression strain.The POM-loaded sponge was found to effectively catalyze the hydroboration of phenylacetylenes,yielding excellent conversion and regioselectivity of up to 96%and 99%,respectively.Its catalytic activity remained unchanged after five reuse cycles.These findings represent a scalable strategy for immobilizing POMs on porous supports.

关键词： cellulose nanofiber polyoxometalates catalyst immobilization hydroboration heterogeneous catalyst