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Chinese Chemical Letters 2014年第11期25卷 1461-1465页

作者： Feng li Chun-Shan Lu xiao-nian li Institute of Industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

The effect of the amount of precipitant ammonia on the Cu0/Cu＋ratio of Cu/Si O2 prepared by the deposition–precipitation method is investigated. Species at different preparation stages, resulted from the amount of ammonia used, are identified by the XRD and FTIR techniques. Chrysocolla together with either copper nitrate hydroxide or copper hydroxide coexist in the uncalcined catalysts. Upon calcination, the latter two species are converted to Cu O particles while chrysocolla remains. Following reduction, Cu O is transformed to metallic Cu and chrysocolla is converted to Cu2 O. The value of Cu0/Cu＋ratio can be evaluated using the peak areas in their TPR profiles. Hydrogenation of dimethyl oxalate（DMO） to ethylene glycol（EG） shows that the selectivity of EG depends on the Cu0/Cu＋ratio. Catalyst prepared with the addition of ammonia solution at n（NH3）/n（Cu2＋） = 0.9 for precipitation–deposition gains a more suitable Cu0/Cu＋ratio upon reduction and thus has a higher selectivity for EG.

关键词： Amount of ammonia Deposition–precipitation Chrysocolla Copper nitrate hydroxide Copper hydroxide DMO hydrogenation

Visible-light photoredox-mediated oxidation of N-methyl tertiaryamines under catalyst free conditions:Direct synthesis of methylene-bridged bis-1,3-dicarbonyl compounds

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Chinese Chemical Letters 2014年第4期25卷 545-548页

作者： xiao-Jun Dai xiao-liang Xu Dong-Ping Cheng xiao-nian li Institute of Industrial Catalysis College of Chemical Engineering and Materials ScienceZhejiang University of Technology College of Pharmaceutical Science Zhejiang University of Technology

Mediated by visible light-induced photoredox catalysis and free of other catalysts, a new and efficient synthesis of methylene-bridged bis-l,3-dicarbonyl derivatives has been developed. A variety of N-methyl tertiarya... 详细信息

关键词： Photochemistry Oxidation Aliphatic tertiaryamine Catalyst free

Polyprenylated acylphloroglucinols from the fruits of Hypericum henryi

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Science China Chemistry 2016年第9期59卷 1216-1223页

作者： Yang liao Shu-Ya Yang xiao-nian li Xing-Wei Yang Gang Xu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China University of Chinese Academy of Sciences Beijing 100049 China

Hyphenrones R–X(1–7), seven new polyprenylated acylphloroglucinols derivatives, were isolated from the fruits of Hypericum henryi, together with eight know analogues. Compounds 1 and 2 were elucidated to possess complex caged skeleton, while compounds 3–6 shared a common 3,9-epoxy moiety deriving from the normal polyprenylated acylphloroglucinols with a bicyclo[3.3.1]nonane-2,4,9-trione core. The new structures were elucidated on the basis of the interpretation of nuclear magnetic resonance(NMR) data, circular dichroism(CD) comparison, and single-crystal X-ray diffraction. In the bioassay, several compounds exhibited inhibitory activities against human tumor cell lines in vitro.

关键词： polyprenylated acylphloroglucinols Hypericum henryi hyphenrones R-X antitumor

Synthesis of carbon-supported Pd/SnO_2 catalyst for highly selective hydrogenation of 2,4-difluoronitrobenzene

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Chinese Chemical Letters 2014年第8期25卷 1137-1140页

作者： Jia Zhao Lei Ma xiao-liang Xu Feng Feng xiao-nian li Industrial Catalysis Institute of Zhejiang University of Technology

Halogenated anilines have a wide range of applications in the production of pharmaceuticals and agrochemical substances, and thus it is of great importance to develop highly active and selective catalysts for the hydrogenation of halogenated nitrobenzenes. We approach this challenge by probing noble metal/non-noble metal oxide nanoparticles（NPs） catalysts. Carbon-supported Pd/SnO2catalysts were synthesized by the chemical reduction method, and their catalytic activity was evaluated by the hydrogenation reaction of 2,4-difluoronitrobenzene（DFNB） to the corresponding 2,4-difluoroaniline（DFAN）, showing a remarkable synergistic effect of the Pd and SnO2 NPs. The as-prepared Pd/SnO2/C catalysts were characterized using TEM, XRD, H2 TPD and XPS techniques. Modifications to the electronic structure of the Pd atoms through the use of SnO2 led to the suppression of the hydrogenolysis of the C–F bond and the acceleration of nitrosobenzene（DFNSB） conversion and consequently, resulted in the inhibition of the formation of reactive by-products and may be responsible for the enhancements observed in selectivity.

关键词： Tin dioxide Palladium Selective hydrogenation 2.4-Difluoronitrobenzene

Pestaloamides A and B,two spiro-heterocyclic alkaloid epimers from the plant endophytic fungus Pestalotiopsis ***30

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Science China Chemistry 2020年第9期63卷 1208-1213页

作者： xiao-Zheng Su Yi-Ying Zhu Jian-Wei Tang Kun Hu xiao-nian li Han-Dong Sun Yan li Pema-Tenzin Puno State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesYunnan Key Laboratory of Natural Medicinal ChemistryKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

Pestaloamides A and B(1 and 2),two novel alkaloids featuring an unprecedented spiro[imidazothiazoledione-alkylidenecyclopentenone]scaffold,were obtained from the cultures of an endophytic fungus Pestalotiopsis ***30 which inhabited the stems of Isodon *** planar structures and absolute configurations were fully determined by extensive spectroscopic analysis and X-ray *** addition,both compounds 1 and 2 showed the latent tumor immunotherapy activity through markedly promoting the cell surface engagement of NKG2 D ligands involving MICA/B and ULBP1 in HCT116 cells.

关键词： alkaloids endophytic fungus structure elucidation tumor immunotherapy

Study on the Precursor Phase Composition of Fused Iron Catalyst for Fischer-Tropsch Synthesis

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Chinese Chemical Letters 2005年第10期16卷 1393-1396页

作者： Ju li SHEN Hua Zhang liU xiao nian li Weng Feng HAN Yi Fan ZHENG Catalysis Institute of Zhejiang University of Technology State Key Laboratory Breeding Base of Green-Chemistry Synthesis Technology Hangzhou 310014

The effect of the precursor composition of fused iron catalyst on the performance of Fischer-Tropsch synthesis was investigated. XRD, BET and CO2 adsorption experiments were carried out to provide better insight into the relationship therein. The results showed that the selectivity of C5＋ hydrocarbon products was dependent on the mole ratio of Fe^2＋/Fe^3＋, which was represented by a hump-shaped curve. Catalysts with precursors containing Fe3O4 phase favored the magnetite spinal formation during F-T reaction, while Fe（1-x）O-based catalysts were more likely to favor the formation and growth of the iron carbide crystals.

关键词： Fischer-Tropsch synthesis fused iron catalyst precursor selectivity.

Dual activation and C-C coupling on single atom catalyst for CO_(2) photoreduction

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npj Computational Materials 2023年第1期9卷 110-117页

作者： u-li Sun Cun-biao lin Wei Zhang Qing Chen Wen-xian Chen xiao-nian li Gui-lin Zhuang H-PSI Computational Chemistry Lab Institute of Industrial CatalysisState Key Laboratory Breeding Base of Green-Chemical Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310032PR China Surface Lab 10 Institute of PhysicsChinese Academy of SciencesBeijingPR China

An excellent single-atomic photocatalyst,Ti@C_(4)N_(3),is theoretically found to effectively convert CO_(2) to C_(2)H_(6) by density functional theory(DFT)calculations and non-adiabatic molecular dynamics(NAMD)*** Ti@C_(4)N_(3) photocatalyst has remarkable stability both thermally,chemically,and ***,it has strong absorption properties(λ=327.77 and 529.61 nm),suitable band positions,and a long photogenerated electron lifetime(τ_(e)=38.21 ps),allowing photogenerated electrons to migrate to the ***,the high-valence active site effectively activates two CO_(2) through dual activation:Under light irradiation,the weakly adsorbed CO_(2) undergoes photo-induced activation by the photoelectron of conduction band minimum(CBM);without light,the high Lewis acidity of the Ti site induces CO_(2) activation through back-donatingπ-*** simulation results uncovered that dual activation of CO_(2) is attributed to the thermal and photonic ***,two activated CO_(2) species under light easily couple to form oxalate with the barrier of 0.19 eV,and further reduced to C_(2)H_(6) with a low activation energy of 1.09 eV.

关键词： activation catalyst coupling

Two new guaianolide-type sesquiterpenoids from Kadsura interior

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Chinese Chemical Letters 2013年第2期24卷 111-113页

作者： Ke Dong Jian-Xin Pu Xue Du xiao-nian li Han-Dong Sun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciences

Received 22 November 2012 Received in revised form 25 December 2012 Accepted 2B December 2012 Available online 4 February 2013

关键词： Kadsura interior4 8 9β-Dihydroxy-1 a 5a-H-guaia-6 10( 14)-dien4β 9β 10β-Trihydroxy-1a.5a-H-guaia-6-enX-ray technique

The chemical constituents from Schisandra propinqua var. intermedia

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Chinese Chemical Letters 2008年第12期19卷 1450-1452页

作者： Hong Mei li Wei Guang Wang xiao nian li Yong Zhao Rong Tao li Han Dong Sun The College of life Science and Technology Kunming University of Science and Technology Kunming 650224 China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

A new cinnamic acid monoterpenoid ester, intermedin C （1）, was isolated from the aerial parts of Schisandra propinqua var. interthedia. The structure of 1 was elucidated by spectroscopic methods including extensive ... 详细信息

关键词： Schisandra propinqua Monoterpenoid Intermedin C

Improvement of the stability of Hg/AC catalysts by CsCl for the high-temperature hydrochlorination of acetylene

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Chinese Chemical Letters 2016年第6期27卷 822-826页

作者： xiao-Long Xu Jia Zhao Chun-Shan Lu Tong-Tong Zhang xiao-Xia Di Shan-Chuan Gu xiao-nian li Institute of Industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

Activated carbon-supported mercuric chloride（HgCl2） is used as an industrial catalyst for acetylene hydrochlorination. However, the characteristic of easy sublimation of HgCl2 leads to the deactivation o the catalyst. Here, we showed that the thermal stability of the Hg/AC catalyst can be evidently improved when Cs Cl is added into the Hg/AC catalyst. Compared with the pure Hg/AC catalyst, the sublimation rate of HgCl2 from the Hg–Cs/AC catalyst decreased significantly and the Hg–Cs/AC catalyst showed bette catalytic activity and stability in the reaction. This promoting effect is related to the existence of cesium mercuric chlorides（CsxHgyCl（x＋2y）） highlighted by XRD, HR-TEM and EDX analyses. Thus, reacting HgCl2 with alkali chlorides to form alkali-mercuric chlorides may be a key to design highly efficient and thermally stable mercuric chloride catalyst for hydrochlorination reactions.

关键词： Cesium chloride Mercuric chloride Sublimation Hydrochlorination of acetylene Cesium–mercuric chlorides