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Science China Chemistry 2010年第3期53卷 598-603页

作者： Zhang, Li Fang Wang, Yan Wang, Pei Shen, Li Juan Institute of Material Chemistry Shanxi Normal University Linfen 041004 China

Single component rare earth aryl oxides substituted by various alkyl groups [Ln(OAr)3] such as methyl,isopropyl,and tertbutyl have been developed to initiate the ring-opening polymerization of 2,2-dimethyltrimethylene carbonate(DTC).The catalytic activity of rare earth aryl oxides,characteristics of the ring-opening polymerization as well as the polymerization kinetics and mechanism were intensively *** experimental results turn out that the catalytic activity of Ln(OAr)3 changes in good concordance with variation of ligands' structure and number of alkyl groups on benzene *** greater the ability of electron-donation of alkyl groups,the greater the catalytic ***,the greater the number of substituted alkyls on benzene ring,the greater the catalytic *** results show that rare earth tris(2,4,6-tri-tert-butylphenolate)s [Ln(OTTBP)3](Catalyst 1) exhibit rather great activity in all lanthanide aryl *** of the polymerization mechanism by 1H NMR spectroscopy revealed that the DTC monomer inserted into the growing chains with acyloxygen bond cleavage.

关键词： ring-opening polymerization 2 2-dimethyltrimethylene carbonate rare earth aryl oxides

Catalyst-controlled diastereoselective ring-opening formal [3+2]-cycloadditions of arylvinyl oxirane 2,2-diesters with cyclic N-sulfonyl imines

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Science China Chemistry 2020年第6期63卷 785-791页

作者： Jun-An Xiao Xiu-Liang Cheng Hai Peng Jin-Lian Li Zhen-Zhen Xie Wen-Qiang Chen Zhi-Ping Liu Qi Xiao Wei Su Hua Yang Guangxi Key Laboratory of Natural Polymer Chemistry and Physics Nanning Normal UniversityNanning 530001China College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

A diastereoselectivity-controllable formal[3+2]-cycloaddition of arylvinyl oxirane 2,2-diesters with cyclic N-sulfonyl imines is developed,affording the corresponding tricyclic oxazolidine derivatives in moderate to excellent yields with excellent diastereoselectivities in the presence of palladium(0)or scandium(III)*** protocol allows selective synthesis of diastereomers of tricyclic oxazolidine derivatives under switchable and mild *** transformations of the obtained products were conducted by removing ester groups and arylvinyl moieties.

关键词： [3+2]-cycloaddition cyclic N-sulfonyl imine donor-acceptor oxirane ring-opening

ring-opening Polymerization of Lactones With Rare Earth Compound as Catalyst—— Polymerization of ε-caprolactone by Rare Earth Alkoxides

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Chinese Science Bulletin 1994年第13期39卷 1096-1100页

作者：沈之荃申有青孙俊全张富尧张一烽

Recently, much attention has been paid to poly (ε-caprolactone) (PCL) since it is biodegradable with the release of nontoxic byproduct in vivo and miscible with a variety of polymers. Therefore it has already been used as materials of sustaining drug release, dental prostheses, as well as a new raw material of polyurethanes and long life plasticizer of poly(vinyl chloride).

关键词： ring-opening polymerization c-caprolactone rare earth alkoxides.

ring-opening Polymerization of Chloromethylthiirane by Rare Earth Coordination Catalysts

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Chinese Science Bulletin 1994年第14期39卷 1188-1191页

作者：沈之荃孙维林张一烽 Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 PRC

Polychloromethylthiirane （PCMT） may become a novel polymer material with excellent oil resistance, heat resistance, solvent resistance and combustion resistance because of the sulfur and chlorine atoms in the polymer chain. Besides, the chloromethyl group can be further modified to synthesize functional polymers. Furukawa et al. reported in 1952 that CMT can be polymerized by H2SO4 giving a polymer with the molecular weight of 1000. Zussman et al. found that only a few catalysts, such as BF3·Et2O, CF3SO3H, H2SO4, could be used for the ring-opening polymerization of CMT in the 1980s. PCMT was obtained at a temperature of -78℃ after a few days to several weeks, and the catalytic activity was not mentioned. There is no other information concerning the ring-opening polymerization of CMT until now, which implies that CMT is a rather difficult monomer to be ring-opening polymerized.

关键词： rare earth coordination catalyst polychloromethylthiirane ring-opening polymerization.

Readily Prepared and Tunable Ionic Organocatalysts for ring-opening Polymerization of Lactones

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Chinese Journal of Polymer Science 2019年第12期37卷 1205-1214,I0005页

作者： Zhuo-Lun Jiang Jun-Peng Zhao Guang-Zhao Zhang Faculty of Materials Science and Engineering South China University of Technology

Highly potent ionic organocatalyst is developed for room-temperature controlled ring-opening polymerization(ROP)of lactones,includingδ-valerolactone,ε-caprolactone,andδ-*** catalysts are prepared by simply mixing tetra-n-butyl ammonium hydroxide and a(thio)urea at elevated temperature under vacuum,and used in cooperation with an alcoholic *** performance of the catalyst is readily adjusted and optimized through variation of the(thio)urea precursor,catalyst composition,and reaction ***-derived catalysts are generally superior to thiourea-derived *** with proper N-substituents,the catalyst affords both high polymerization efficiency and high selectivity for monomer enchainment over macromolecular transesterification,even at high monomer conversion and/or substantially extended reaction *** addition to acidity,structural symmetry of the urea also proves decisive for the catalytic activity,which enables a catalyst-assisted proton transfer process for the ring-opening of lactone and thus provides a novel mechanistic insight for ROP catalyzed by hydrogen-bonding type bifunctional ionic organocatalysts.

关键词： Organocatalytic polymerization ring-opening polymerization Polyester

(Arylimido)vanadium(V)-Alkylidene Complexes as Catalysts for ring-opening Metathesis Polymerization(ROMP) of Cyclic Olefins: Ligand Design for Exhibiting the High Activity

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Chinese Journal of Polymer Science 2019年第10期37卷 943-950,I0002页

作者： Kotohiro Nomura Sapanna Chaimongkolkunasin Department of Chemistry Graduate School of Science Tokyo Metropolitan University

(Imido)vanadium(V)-alkylidene complexes of type V(CHSiMe3)(NR)(OR?)(PMe3)2 [R = Ad, C6H5, 2,6-Me2C6H3, 2,6-Cl2C6H3;R?= 2,6-Me2C6H3, 2,6-i Pr2C6H3, 2,6-F2C6H3, C6F5, C6Cl5] exhibited from moderate to remarkable catalytic activities for ringopening metathesis polymerization(ROMP) of norbornene(NBE). The catalytic activities were affected by the ligand substituents, and V(CHSiMe3)(N-2,6-Cl2C6H3)(OC6X5)(PMe3)2(X = F, Cl) demonstrated the exceptionally high catalytic activities for ROMP of *** complexes polymerized cycloheptene(CHPE) and cis-cyclooctene(COE), and ROMP of COE by the OC6 Cl5 analogue proceeded in a living manner even at 80℃, and the activity increased with increasing the temperature up to 120 ℃. Highly active catalysts for ROMP of cyclic olefins(NBE, cyclopentene, and CHPE) can be generated in situ by premixing isolated V(CHSiMe3)(NC6F5)(O-2,6-iPr2C6H3)(PMe3)2 with 1.0 equiv. of C6F5OH or C6Cl5OH via immediate phenoxy exchange;the activity was affected by the kind of phenol added [TOF in the ROMPs of NBE: 4.62 × 10^4 min^–1(upon addition of C6F5OH) versus 37.3 min^–1(none)].

关键词： Olefin metathesis Molecular catalyst ring-opening metathesis polymerization Cyclic olefin Vanadium catalyst

Lewis acid/base modulation in β-diiminate zinc-catalyzed switchable ring-opening polymerization of rac-lactide

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Science China Chemistry 2019年第4期62卷 475-478页

作者： Pan Zhang Minhui Zhao Wenmin Pang Changle Chen Hefei National Laboratory for Physical Sciences at the Microscale Chinese Academy of Sciences Key Laboratory of Soft Matter ChemistryDepartment of Polymer Science and Engineering University of Science and Technology of China

Two β-diiminate zinc complexes were prepared and found to show high activity and well-controlled catalytic behavior in the ring-opening polymerization of rac-lactide. Coordination of the Lewis acid to the zinc complexes completely terminated the polymerization. The coordinated Lewis acid was easily cleaved by using a Lewis base, so that the polymerization could ***, switchable polymerization could be realized by the subsequent addition of a Lewis acid and a Lewis base. This work provides a new strategy to control the ring-opening polymerization of rac-lactide.

关键词： ring-opening polymerization β-diimine zinc catalysts modulation

Cobalt-Catalyzed Enantioselective ring-opening Reactions of Oxa- and Aza-bicyclic Alkenes with Alkenylboronic Acids

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Chinese Journal of Chemistry 2022年第2期40卷 190-194页

作者： Di Zhu Yongmei Zhao Qinglei Chong Fanke Meng State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing 102249China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Catalytic enantioselective ring-opening of oxa-and aza-bicyclic alkenes with readily available accessible alkenylboronic acids,promoted by a chiral phosphine-Co complex,is *** a process represents the unprecedented Co-catalyzed introduction of various alkenyl groups onto the oxa-and aza-bicyclic alkenes,affording a wide range of multisubstituted functionalized cyclohexenes in up to 98%yield and 99.5:0.5 er.

关键词： Cobalt ring-opening Enantioselective catalysis Bicyclic alkene Alkenylboron

Facile access to β-hydroxyl ketones via a cobalt-catalyzed ring-opening/hydroxylation cascade of cyclopropanols

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Chinese Chemical Letters 2023年第3期34卷 322-325页

作者： Shengxian Zhai Shuxian Qiu Shuangtao Yang Xingyuan Gao Xinyu Feng Chenzhe Yun Ning Han Yongsheng Niu Jing Wang Hongbin Zhai College of Chemistry&Environmental Engineering Anyang Institute of TechnologyAnyang 455000China Department of Chemistry and Material Science Engineering Technology Development Center of Advanced Materials&Energy Saving and Emission Reduction in Guangdong Colleges and UniversitiesGuangdong University of EducationGuangzhou 510303China State Key Laboratory of Chemical Oncogenomics and Key Laboratory of Chemical Genomics Shenzhen Engineering Laboratory of Nano Drug Slow-ReleaseShenzhen Graduate School of Peking UniversityShenzhen 518055China Shenzhen Bay Laboratory Shenzhen 518055China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300071China

A cobalt-catalyzed ring-opening/hydroxylation cascade of highly strained cyclopropanols has been developed for the first time. The reaction was conducted under open-air atmosphere to afford a broad series of structurally diverse β-hydroxy ketones in moderate to good yields with high *** protocol features mild reaction conditions, simple operation, high-functional-group tolerance, facile scalability, and heterocycle compatibility.

关键词： Cobalt catalysis ring-opening Cyclopropanol β-Hydroxy ketone Cascade reaction

A novel four-component reaction involving ring-opening/recyclization of 1,3-thiazolidinedione

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Science China Chemistry 2010年第4期53卷 863-868页

作者： SUN Jing, XIA ErYan, ZHANG LiLi & YAN ChaoGuo College of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou 225002, China 1. College of Chemistry & Chemical Engineering Yangzhou University Yangzhou 225002 China

The multicomponent reactions of 1,3-thiazolidinedione, malononitrile, aromatic aldehydes and α-phenylethylamine or β-phenylethylamine in acetonitrile at room temperature produce dihydrothiophene ureidoformamide derivatives in moderate yields through a domino ring-opening/recyclization reaction of 1,3-thiazolidinedione. On treatment with DDQ, dihydrothiophenes are dehydrogenated to convert efficiently to thiophenes in the mild condition.

关键词： multicomponent reaction ring-opening recyclization dihydrothiophene thiazolidinedione