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Asymmetric oxygen-bridged Bi-In dual sites for efficient photothermal CO2 methanation 认领 引用
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作者 Mang Zheng Qi Li +4 位作者 Qianxi Liu Huiquan Gu Mingyang Liu Qi Liu Baojiang Jiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2026年第4期351-362,共12页
Photothermal coupling catalytic CO2/H2O to CH4 is recognized as an effective strategy for addressing environmental concerns and energy crisis.However,hydrogen evolution reaction(HER)competition and weak inter... Photothermal coupling catalytic CO2/H2O to CH4 is recognized as an effective strategy for addressing environmental concerns and energy crisis.However,hydrogen evolution reaction(HER)competition and weak intermediate adsorption limiting CH4 selectivity and yield during the reaction process.Herein,we incorporate Bi into the In2O3 lattice to create an oxygen-bridged asymmetric bimetallic In-O-Bi(In-O-Bi bridge)sites.The optimized Bi/In2O3 catalyst achieves CH4 yield of 214.1μmol·g-1 with 96.7%selectivity.The exceptional catalytic activity of Bi/In2O3 stems from two key synergistic effects:(1)the cooperative interaction between Bi and In as p-block metals effectively suppress the competing HER,and(2)the unique In-O-Bi bridge configuration induces significant electron delocalization through p-orbital hybridization.This electronic modulation creates highly active catalytic centers,with In sites preferentially facilitating H2O dissociation while Bi sites selectively promote CO2 reduction.Moreover,the electron delocalization effect in the In-O-Bi bridge sites enhances the adsorption and electron transfer capabilities of the Bi/In2O3 surface for key CHO species,and reduces the energy barrier,thereby enabling efficient CH4 production.These findings provide crucial insights into the design of photothermal catalysts,highlighting the transformative potential of oxygen-bridged asymmetric bimetallic units in efficient CO2 methanation and sustainable energy technologies. 展开更多
关键词 Photothermal catalysis CO2methanation Orbital hybridization Electron delocalization In-O-Bi bridge sites
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Interface engineering of covalent β-ketoenamine-bridged S-scheme heterojunction for synergistic solar-powered CO2-to-CO conversion paired with selective alcohol oxidation 认领 引用
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作者 Haopeng Jiang Jinhe Li +3 位作者 Xiaohui Yu Huilong Dong Weikang Wang Qinqin Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2026年第1期113-122,共10页
To address persistent challenge of charge recombination in semiconductor photocatalysis,we engineered an S-scheme heterojunction via covalentβ-ketoenamine bridges between zirconium-based MOFs and triazine-COFs(Zr-BTB... To address persistent challenge of charge recombination in semiconductor photocatalysis,we engineered an S-scheme heterojunction via covalentβ-ketoenamine bridges between zirconium-based MOFs and triazine-COFs(Zr-BTB-COF).This dual-functional system pioneered a“one-photon,two-value”strategy for simultaneous CO2-to-CO reduction and 4-methoxybenzyl alcohol-to-anisaldehyde oxidation,enabling solar-driven carbon refineries.Synergistic in-situ XPS analysis and density functional theory calculations unambiguously validated the S-scheme charge transfer mechanism.The covalent interface overcame lattice mismatch constraints while Fermi-level alignment generated an enhanced built-in electric field(9.8 times stronger than pristine Zr-BTB-NH2),achieving ultrafast charge separation.Low-energy carrier recombination through theβ-ketoenamine bridge preserved high-potential carriers(-1.61 V for CO2reduction;+2.22 V for alcohol oxidation).Critically,this architecture reduced the activation energy barrier for the rate-limiting*COOH→*CO step toΔG=0.65 eV,a 42%reduction versus isolated Zr-BTB-NH2.Through concerted thermodynamic and kinetic optimization,the covalent Zr-BTB-COF achieved high CO and anisaldehyde yields(71.9 and 44.7μmol·g-1·h-1)with internal quantum efficiency of 3.75%(365 nm).This bond-resolved interface engineering paradigm establishes a new design framework for synchronizing carbon-neutral cycles with high-value chemical synthesis. 展开更多
关键词 S-scheme heterojunction Covalentβ-ketoenamine bridge Photocatalytic CO2reduction
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Diverse synthesis of bridged bicyclo[3.2.1]octa-2,6-diene and tricyclo[3.2.1.02,7]oct-3-ene frameworks via stepwise cascade reactions 认领 引用
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作者 Ze-Hong Zheng Mu-Qiu Chen +6 位作者 Jin Zhou Jie Wang Yan-Rong Wei Cheng Peng Gu Zhan Qian-Qian Yang Bo Han 《Chinese Chemical Letters》 SCIE CAS CSCD 2025年第12期212-217,共6页
Strained bridged rings bicyclo[3.2.1]octane and tricyclo[3.2.1.02,7]octane are prevalent in natural products known for their significant biological activities.However,strategies for efficiently synthesizing these c... Strained bridged rings bicyclo[3.2.1]octane and tricyclo[3.2.1.02,7]octane are prevalent in natural products known for their significant biological activities.However,strategies for efficiently synthesizing these complex frameworks from simple starting materials via de novo synthesis remain underexplored.This article presents an efficient strategy that combines phosphine catalysis and photocatalysis to execute a stepwise tandem reaction involving allenoates and α-cyano cinnamaldehydes,including[3+2]cyclization,[5+2]cyclization,acyl transfer,and decarboxylation reactions,synthesizing a series of functional bicyclo[3.2.1]octa-2,6-diene and tricyclo[3.2.1.02,7]oct-3-ene skeleton derivatives with excellent chemoselectivity demonstrated throughout the process.Meanwhile,the reaction can also be performed via a onepot,scalable phosphine/photocatalytic cascade process,efficiently yielding the bridged products which can serve as versatile intermediates for further applications. 展开更多
关键词 Allenoate Bridged bicyclo[3.2.1]octa-2 6-diene frameworks Tricyclo[3.2.1.02 7]oct–3-ene frameworks Phosphine catalysis Di-π-methane rearrangement reaction
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Al-O bridged NiFeO_x/BiVO4photoanode for exceptional photoelectrochemical water splitting 认领 引用
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作者 Lina Wang Hairu Wang +4 位作者 Qian Bu Qiong Mei Junbo Zhong Bo Bai Qizhao Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2025年第4期392-397,共6页
Developing BiVO4photoanode with efficient carrier transfer and fast water oxidation kinetics is the permanent pursuit to achieve the state-of-art solar-driven photoelectrochemical(PEC)water splitting.The capacity t... Developing BiVO4photoanode with efficient carrier transfer and fast water oxidation kinetics is the permanent pursuit to achieve the state-of-art solar-driven photoelectrochemical(PEC)water splitting.The capacity to increase the PEC activity of BiVO4by loading oxygen evolution co-catalysts(OECs)has been proven,however it suffers from sluggish charge carriers dynamics brought on by the complicated interface between BiVO4and OECs as well as poor long-term durability.Herein,we connected OECs(NiFeOx)and photoanode with a Al-O bridge for bettering the PEC performance of BiVO4.The Al-O bridge served as a channel to extract hole from BiVO4to Ni Fe Ox,thus boosting charge carriers separation and preventing BiVO4 from photo-corrosion.The Al-O bridging photoanode(NiFeOx/Al2O3/BiVO4)demonstrated a high photocurrent density of 5.87 m A/cm2at 1.23 V vs.RHE and long-term photostability in comparison to Ni Fe Ox/BiVO4photoanode.This study proposes a unique technique to boost charge carriers separation between BiVO4 and OECs for high-efficiency solar-driven PEC water splitting. 展开更多
关键词 PEC Photoanode Bridge OECs Water splitting
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Hydrothermal synthesis and catalytic performance of bulky titanium silicalite-1 aggregates assembled by bridged organosilane 认领 引用 被引量：4
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作者 Li Chen Teng Xue +4 位作者 Jian Ding Hai Hong Wu Kun Zhang Peng Wu Ming‐Yuan He 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期275-282,共8页
A facile and effective method to synthesize TS‐1zeolite aggregates has been presented.The crystallization of silanized seeds and nanocrystallites led to large and irregular TS‐1zeolite aggregates ranging from5to40μ... A facile and effective method to synthesize TS‐1zeolite aggregates has been presented.The crystallization of silanized seeds and nanocrystallites led to large and irregular TS‐1zeolite aggregates ranging from5to40μm in size,based on the special sol‐gel chemistry of bridged organosilane.Epoxidation of1‐hexene and cyclohexene was used as a probe reaction to investigate the catalytic performance of the resulting materials.These TS‐1zeolite aggregates possessed both the conventional nanoparticle properties of TS‐1zeolites and variable surface hydrophilic/hydrophobic features,which enhanced the catalytic properties of hydroperoxides for alkene epoxidation.Moreover,the large aggregates effectively simplified the separation procedure during preparation and catalytic reactions. 展开更多
关键词 Bridged organosilane TS‐1 seeds TS‐1 nanocrystallites Zeolite aggregation Alkene epoxidation
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Comparison Between the Effects of 2-Selenium Bridgedβ-Cyclodextrin and Ebselen on Treating SHRsp Stroke 认领 引用 被引量：3
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作者 JIA Zhi-dan LIN Feng +3 位作者 LIU Lei MU Ying YAN Gang-lin LUO Gui-min 《Chemical Research in Chinese Universities》 SCIE CAS 2008年第3期322-329,共8页
A glutathione peroxidase(GPX)mimic,2-selenium bridgedβ-cyclodextrin(2-SeCD),was synthesized.In order to examine its role and mechanism in treating stroke we chose stroke-prone spontaneously hypertensive rats(SHRsp)as... A glutathione peroxidase(GPX)mimic,2-selenium bridgedβ-cyclodextrin(2-SeCD),was synthesized.In order to examine its role and mechanism in treating stroke we chose stroke-prone spontaneously hypertensive rats(SHRsp)as animal model.56 SHRsps of 8-week olds were randomly divided into several groups:test groups(low,moderate,high dose of 2-SeCD)and control groups(positive and negative).After onset of the stroke,the rats in test groups were orally administrated with different amounts of 2-SeCD,the positive control group with ebselen,and the negative control group with drinking water.The treatment lasted two weeks,followed by observation of the rats for 10 days,meanwhile blood pressure,biochemical parameters of plasma,and the contents of nitric oxide(NO)and malondialdehyde(MDA)in plasma and brain were determined.The results show that there were significant differences in contents of NO and MDA in plasma and brain between the test groups(high,moderate dose of 2-SeCD)and negative control group.The NO contents of the test groups were obviously higher than that of the negative control group(P〈0.01).The MDA contents of the test groups(high,moderate dose of 2-SeCD)were obviously lower than that of the negative control group(P〈0.01).The mechanism of 2-SeCD in treating stroke was discussed,which maybe related to the increase of NO and the decrease of MDA in plasma and brain tissue,but the exact mechanism should be further studied.Moreover,the tendencies of changes in systolic blood pressure,contents of NO and MDA,and other physiological parameters for the test groups were shown to be much better than the corresponding parameters for the positive group(the group with ebselen)(P〈0.05),indicating that the treatment effect of 2-SeCD is better than that of ebselen. 展开更多
关键词 2-Selenium bridgedβ-cyclodextrin Glutathione peroxidase Enzyme mimic Stroke Stroke-prone spontaneously hypertensive rat Nitric oxide Malondialdehyde
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Stereoselective construction of azepine-containing bridged scaffolds via organocata-lytic bicyclization of yne-allenone esters with nitrones 认领 引用 被引量：1
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作者 Meng-Fan Li Shao-Qing Shi +6 位作者 Ting Xu Qian Zhang Wen-Juan Hao Shu-Liang Wang Jianyi Wang Shu-Jiang Tu Bo Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第4期309-312,共4页
A new organocatalytic double annulation cascade involving scissionecombination of N-O bonds of nitrones is reported for the first time, and used to produce a range of hitherto unprecedented tricyclic bridged-fused ben... A new organocatalytic double annulation cascade involving scissionecombination of N-O bonds of nitrones is reported for the first time, and used to produce a range of hitherto unprecedented tricyclic bridged-fused benzo[d]azepines bearing three stereogenic centers with moderate to good yields and complete diastereoselectivity. A quinine-catalyzed reaction of yne–allenone esters with nitrones worked well and provided a convergent and regioselective pathway to access these three-dimensional scaffolds from the planar conjugated system. Density functional theory(DFT) calculations have been applied to understand the key process for forming diradical intermediates. 展开更多
关键词 Bicyclization Diastereoselectivity Organocatalysis Bridged heterocycles YNE-allenone esters Nitrones
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Synthesis, Characterization and Application of A Novel Carbon Bridged Half-metallocene Chromium Catalyst for Methyl Methacrylate Polymerization 认领 引用 被引量：2
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作者 程正载 GONG Kai +5 位作者 WANG Yang ZHOU Xue ZHANG Weixing LI Yin SUN Junquan LI Wenbing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1294-1301,共8页
A new carbon bridged cyclopentadienyl chromium complex of the type [（C5H4）C（CH3）2 CH2（C5H4N）]CrCl2 was prepared by treatment of CrCl3·（THF）3 in THF solution with the lithium salt of ligand containing cycl... A new carbon bridged cyclopentadienyl chromium complex of the type [（C5H4）C（CH3）2 CH2（C5H4N）]CrCl2 was prepared by treatment of CrCl3·（THF）3 in THF solution with the lithium salt of ligand containing cyclopentadienyl and pyridyl groups. The chromium complex was characterized by 1H NMR and elemental analysis（EA）, and the crystal structure was determined by X-ray diffraction analysis. Activated by Al（i-Bu）3, the chromium complex displayed a very high activity for methyl methacrylate（MMA） polymerization. After 24 hours,more than 95.5% MMA was converted to polymethyl methacrylate（PMMA） with a viscosity average molecular weight（Wη） of 416000 g·mol-1 at 60 ℃ for MMA/ Al（i-Bu）3 /chromium catalyst molar ratio of up to 2000：20：1. Effects of temperature, molar ratios of MMA/catalyst and catalyst/cocatalyst on the polymerization have been studied. The high conversion of MMA and high molecular weight of PMMA with narrow molecular weight distribution is caused by the unique stable active site formed by the new chromium complex and aluminum cocatalyst. 展开更多
关键词 metallocene catalyst carbon bridged half-metallocene chromium crystal structure MMA polymerization PMMA
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Synthesis and Crystal Structure of the Ladder-like Organotin Complex: μ-pentaoxygen bridged penta(bis-benzyltin) bis-salicylate 认领 引用 被引量：8
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作者 WANG Jian-Qiu CHEN Zhi-Min ZENG Rong-Ying KUANG Dai-Zhi FENG Yong-Lan ZHANG Fu-Xing 《Chinese Journal of Structural Chemistry》 SCIE CAS 北大核心 2005年第12期1387-1392,共6页
A novel organotin complex of μ-pentaoxygen bridged penta（bis-benzyltin） bissalicylate has been synthesized by the reaction of bis-benzyltin oxide and salicylic acid and its structure has been determined by X-ray di... A novel organotin complex of μ-pentaoxygen bridged penta（bis-benzyltin） bissalicylate has been synthesized by the reaction of bis-benzyltin oxide and salicylic acid and its structure has been determined by X-ray diffraction. The crystal belongs to monoclinic, space group P21 with a = 1.7206（5）, b = 2.1401（6）, c = 2.1488（6）nm, β= 93.325（5）°, V = 7.899（4） nm^3, Z = 4, Dc = 1.564 g/cm^3,μ（MoKα） = 16.17cm^-1, Mr = 1859.94, F（000） = 3692, R1= 0.0755 and wR2= 0.1557. According to structural analysis, the coordination geometry of tin is a distorted trigonal bipyramid, and the ladder-like structure is shaped by four Sn2O2 planar four-membered rings. 展开更多
关键词 μ-pentaoxygen bridged penta（bis-benzyltin） bis-salicylate synthesis crystal structure
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Bridged polyhedral oligomeric silsesquioxane(POSS):A potential member of silsesquioxanes 认领 引用 被引量：3
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作者 Jian Kun Hu Qun Chao Zhang Shu Ling Gong 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第2期181-184,共4页
Two novel and well-defined polyhedral oligomeric silsesquioxanes（POSS） with two same Si_8O_（12） cores and a reactive NH group, namely bridged-POSS（2a and 2b）,have been prepared by the traditional ＇corner-cappin... Two novel and well-defined polyhedral oligomeric silsesquioxanes（POSS） with two same Si_8O_（12） cores and a reactive NH group, namely bridged-POSS（2a and 2b）,have been prepared by the traditional ＇corner-capping＇ reaction.X-ray diffraction demonstrates that those two POSS have the similar T_8 structure.From the thermo-gravimetric analysis,bridged-POSS shows the belter thermal degradation stability than the contrastive POSS. 展开更多
关键词 Polyhedral oligomeric silsesquioxane Bridged POSS The corner-capping reaction Organic-inorganic hybrid
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Cyanide-bridged One-dimensional Heterobimetallic Complex cis-[Fe^Ⅱ(phen)2(CN)2Mn^Ⅲ(salen)](PF6):Synthesis,Crystal Structure and Magnetic Properties 认领 引用 被引量：1
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作者 王勇 胡建梅 +1 位作者 李立 李立威 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第2期294-302,共9页
Dicyanide building block cis-Fe（phen）2（CN）2 and [MnⅢ（salen）]（ClO4） have been used to design and synthesize a cyanide-bridged complex, resulting in a heterobimetallic one-dimensional（1D） zigzag chain complex... Dicyanide building block cis-Fe（phen）2（CN）2 and [MnⅢ（salen）]（ClO4） have been used to design and synthesize a cyanide-bridged complex, resulting in a heterobimetallic one-dimensional（1D） zigzag chain complex 1, [cis-Fe（phen）2（CN）2Mn（salen）]（PF6）（phen =1,10-phenanthroline, salen=N,N-ethylenebis-（salicylideneaminato） dianion）. Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in the monoclinic P2（1/c） space group and the asymmetric unit contains one [-NC-Fe（phen）2（μ-CN）-MnⅢ-（salen）-]＋ cation and one PF6- anion. In the cationic structure of 1, each FeⅡ（phen）2（CN）2 connects two [MnⅢ（salen）]＋ with two cyanide groups in a cis-conformation, and in turn each [MnⅢ（salen）]＋ unit links two FeⅡ（phen）2（CN）2 building blocks in a trans-conformation, resulting in a 1D [-NC-FeⅡ-CN-MnⅢ-]n chain. Furthermore, the electronic absorption spectra and electrochemical and magnetic properties of complex 1 have also been studied. 展开更多
关键词 bridged CN Fe PF_6 Synthesis phen salen zigzag conformation monoclinic
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Efficient elimination of carbamazepine using polyacrylonitrile-supported pyridine bridged iron phthalocyanine nanofibers by activating peroxymonosulfate in dark condition 认领 引用
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作者 Zhexin Zhu Wenjie Qian +4 位作者 Zhiguo Shang Xiaoji Ma Zhendong Wang Wangyang Lu Wenxing Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第3期224-236,共13页
The monoaminotrinitro iron phthalocyanine(FeMATNPc)is used to connect with isonicotinic acid(INA)for amide bonding and axial coordination to synthetic a unique catalyst FeMATNPc-INA,which is loaded in polyacrylonitril... The monoaminotrinitro iron phthalocyanine(FeMATNPc)is used to connect with isonicotinic acid(INA)for amide bonding and axial coordination to synthetic a unique catalyst FeMATNPc-INA,which is loaded in polyacrylonitrile(PAN)nanofibers by electrospinning.The introduction of INA destroys theπ-πconjugated stack structure in phthalocyanine molecules and exposes more active sites.The FeMATNPc-INA structure is characterized by X-ray photoelectron spectroscopy and UV-visible absorption spectrum,and the FeMATNPcINA/PAN structure is characterized by Fourier transform infrared spectroscopy and X-ray diffraction.The FeMATNPc-INA/PAN can effectively activate peroxymonosulfate(PMS)to eliminate carbamazepine(CBZ)within 40 minutes(PMS 1.5 mmol/L)in the dark.The effects of catalyst dosage,PMS concentration,pH and inorganic anion on the degradation of CBZ are investigated.It has been confirmed by electron paramagnetic resonance,gas chromatography–mass spectroscopy and free radical capture experiments that the catalytic system is degraded by·OH,SO4·-and Fe(IV)=O are the major active species,the singlet oxygen(1O2)is the secondary active species.The degradation process of CBZ is analyzed by ultra-high performance liquid chromatography-mass spectrometry and the aromatic compounds have been degraded to small molecular acids. 展开更多
关键词 Pyridine bridged iron phthalocyanine Isonicotinic chloride hydrochloride Efficient elimination Peroxymonosulfate activation Degradation pathway
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STRUCTURAL EVIDENCE FOR THE METAL ION BRIDGED LIGANDLIGAND INTERACTION:THE X-RAY CRYSTAL STRUCTURE OF [(2,2'-BIPYRIDYL)(PHENYLMALONATE)COPPER(Ⅱ)] TRIHYDRATE 认领 引用
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作者 Qi Tao LIU Xiang Dong ZHANG +1 位作者 Wei GUAN Jin Yu SUN 《Chinese Chemical Letters》 SCIE CAS 1996年第3期263-264,共2页
The crystal structure of the ternary complex [Cu (L)(2, 2'-bipy)H2 O]·2H2O(L=phenylmalonate) has been determined by X-ray diffraction methods. The copperf(II) centerin five-coordinate Square-pyramidal structu... The crystal structure of the ternary complex [Cu (L)(2, 2'-bipy)H2 O]·2H2O(L=phenylmalonate) has been determined by X-ray diffraction methods. The copperf(II) centerin five-coordinate Square-pyramidal structure.It is of interest in this structure that the complexinvolves a metal ion bridge ligand-ligand aromatic ring stacking interaction 展开更多
关键词 INTERACTION LIGANDLIGAND EVIDENCE THE STRUCTURAL COPPER PHENYLMALONATE BRIDGED BIPYRIDYL
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The Synthesis of Bridged Purine Dinucleoside 认领 引用
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作者 Xiao Hua XU ZhiYuan SUN +2 位作者 Zhong Biao ZHANG Guo Chen CHI RuYu CHEN 《Chinese Chemical Letters》 SCIE CAS 1997年第8期691-692,共2页
Two bridged purine dinucleosides, bis(2-N-acetyl-6-N-alkylylene-2,6-diaminopurine-2',3',5'-triacetyl-beta-D-ribofuranoside), were synthesized fi om the reaction of the key medium 3, 2-acetylamino-6-[1-(1,2... Two bridged purine dinucleosides, bis(2-N-acetyl-6-N-alkylylene-2,6-diaminopurine-2',3',5'-triacetyl-beta-D-ribofuranoside), were synthesized fi om the reaction of the key medium 3, 2-acetylamino-6-[1-(1,2,4-triazolyl)]-purine-2',3',5'-triacetyl-beta-D-ribofuranoside with dialkylamine. 展开更多
关键词 PPM DMSO 亚砜 Cl The Synthesis of Bridged Purine Dinucleoside
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Anion cascade reactions Ⅲ:Synthesis of 3-isoquinuclidone bridged polycyclic lactams 认领 引用
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作者 Zhiguo Zhang Bingbing Shi +4 位作者 Xiyang Cao Nana Ma Hao Wu Xingjie Zhang Guisheng Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第2期426-430,共5页
Bridged polycyclic lactams are important structural units in organic functional materials,natural products,and pharmaceuticals.A flexible and efficient anion cascade reaction was developed for the preparation of bridg... Bridged polycyclic lactams are important structural units in organic functional materials,natural products,and pharmaceuticals.A flexible and efficient anion cascade reaction was developed for the preparation of bridged polycyclic lactams from readily available malonamides and 1,4‑dien-3-ones.Various highly substituted bridged polycyclic lactams were synthesized in good to excellent yields by tandem nucleophilic sequences in the presence of t BuOK in commercially available EtOH solvent at 60℃.Notably,the simple reactions can be run on a gram scale.Mechanistically,bis-Michael addition reaction and hemiaminalization reactions are involved in the tandem transformation. 展开更多
关键词 Anion cascade reactions 3-Isoquinuclidone Bridged polycyclic lactams Bis-Michael addition reaction Hemiaminalization
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SYNTHESIS OF NOVEL THIOPHENEDIMETHYLENE BRIDGED HOMOBINUCLEAR METALLOCENES AND THEIR CATALYTIC PROPERTIES FOR ETHYLENE POLYMERIZATION 认领 引用
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作者 Xi-jie Liu Jun-quan Sun +2 位作者 Hai-ying Zhang Xiao-hui Xiao Feng Lin 《Chinese Journal of Polymer Science》 SCIE EI CAS 2006年第1期21-27,共7页
By treating disodium(thiophenedimethylene)dicyclopentadienide C4H2S(CH2C5H4Na)2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃in THF,two new thiophenedimethylene bridged binuclear metallocenes[Cl2MC5H5][C5H4CH2C... By treating disodium(thiophenedimethylene)dicyclopentadienide C4H2S(CH2C5H4Na)2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃in THF,two new thiophenedimethylene bridged binuclear metallocenes[Cl2MC5H5][C5H4CH2C4H2SCH2C5H4][C5H5MCl2](M=Ti 3,M=Zr 4)were synthesized in high yield and their structures were characterized by^1H-NMR.These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane(MAO).The effects of polymerization temperature,time,concentration of catalyst,molar ratio of MAO/Cat on polymerization were studied in detail.The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts(3,4)reached 2.44×10^5 g PE mol^-1 cat^-1·h^-1,9.61×10^5 g PE mol^-1·cat^-1·h^-1 respectively,which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes(Cp2TiCl2 and Cp2ZrCl2).The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts(3,4)and by mononuclear metallocene catalyst have only single peak,but the former(MWD=3.5-4.7)is obviously broader than the latter(MWD=2.0-2.2). 展开更多
关键词 Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.
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The Assembly and Molecular Structure of a Novel One-dimensionalCyanide-bridged [Ni(pn)_2Ni(CN)_4]_n·nH_2 O Complex 认领 引用
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作者 Xiu Ying ZHANG Dong GUO +5 位作者 Jun Ming TANG Shu Zhong ZHAN Qing Zi HAN Chen Xia DU Yu ZHU Rui Na YANG( Henan Chemistr 《Chinese Chemical Letters》 SCIE CAS 1999年第11期975-978,共4页
The synthesis, structure and characterization of a new one-dimensional cyanide-bridgedcomplex [Ni(pn)_2Ni(CN)4]n'nH2O (where pn = 1,2-diaminopropane) are described. The structure ofthis complex consists of a one-d... The synthesis, structure and characterization of a new one-dimensional cyanide-bridgedcomplex [Ni(pn)_2Ni(CN)4]n'nH2O (where pn = 1,2-diaminopropane) are described. The structure ofthis complex consists of a one-dimensional polymeric chain-Ni(pn)2-NC-Ni(CN)2-CN-Ni(pn)2- inwhich the Ni(II) centers are linked by two CN groups. 展开更多
关键词 Cyanide bridged complex polynuclear complex crystal structure.
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Hydrothermal Synthesis and Crystal Structure of Binuclear Copper(Ⅱ) Complex Bridged by 1,2,4,5- Benzenetetracarboxylato Trivalent Anion 认领 引用
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作者 YUANJi-xin HUMao-lin +1 位作者 LIJu-xia SONGXin-yuan 《Chemical Research in Chinese Universities》 SCIE EI CAS 2005年第1期21-23,共3页
The title complex [(phen) 2Cu(Htcb)Cu(phen) 2]H 3tcb(tcb=1,2,4,5-benzenetetracarboxylato tetravalent anion; phen=1,10-phenanthroline) was synthesized by the hydrothermal synthesis method. The crystal structure was det... The title complex [(phen) 2Cu(Htcb)Cu(phen) 2]H 3tcb(tcb=1,2,4,5-benzenetetracarboxylato tetravalent anion; phen=1,10-phenanthroline) was synthesized by the hydrothermal synthesis method. The crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic system with space group P1, a=1.04174(8) nm, b=1.07119(8) nm, c=1.26360(10) nm, α=98.169(2)°, β=99.679(10)°, γ=93.658(10)°, V=1.37031(18) nm3, Z=1. The two copper(Ⅱ) cations are bridged by Htcb in the monodentate fashion, and have the same five-coordinated environment completed by the four N atoms from the two phen molecules and one O atom from the carboxylic group of Htcb respectively, which can be best described as distorted trigonal-bipyramid geometry. Moreover, the three dimensional network is formed by H-bonding interactions [O…O distance from 0.2506(10) nm to 0.3176(11) nm] and π-π stacking interactions between the phen rings of adjacent binuclear entities with a face-to-face separation of ca. 0.354 nm. 展开更多
关键词 Binuclear complex Copper(Ⅱ) Crystal structure 1,2,4,5-Benzenetetracarboxylato trivalent anion bridged
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Synthesis of Bridged Dianiline Containing Fluorine 认领 引用
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作者 LUO Xinxiang WEN Ruiming +1 位作者 QU Fanqi HUANG Xiaoling 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第3期691-693,共3页
Four novel bridged dianilines containing fluorine were synthesized using 4-chloro-3, 5-dinitrobenzotrifluoride and diamine by two step condensation and reduction. The structures of corresponding compounds were determi... Four novel bridged dianilines containing fluorine were synthesized using 4-chloro-3, 5-dinitrobenzotrifluoride and diamine by two step condensation and reduction. The structures of corresponding compounds were determined by means of IR, NMR and elemental analysis. 展开更多
关键词 4-chloro-3, 5-dinitrobenzotrifluoride bridged dianiline containing fluorine synthesis
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Synthesis and Characterization of Novel Bridged Porphyrins 认领 引用
20
作者 FU Shi-tao WANG Kai +1 位作者 XIE Zheng LI Zao-ying 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第6期949-951,共3页
The reaction of 5-(4-hydroxyphenyl)-10,15,20-triphenyl porphyrin with 2,6-dibromomethylpyridine and 4,4′-dicarboxyl-2,2′-bipyridine respectively gave 2,6-bis-[5,10,15-triphenyl-20-(4-phenoxymethyl)-porphyrin-yl]-pyr... The reaction of 5-(4-hydroxyphenyl)-10,15,20-triphenyl porphyrin with 2,6-dibromomethylpyridine and 4,4′-dicarboxyl-2,2′-bipyridine respectively gave 2,6-bis-[5,10,15-triphenyl-20-(4-phenoxymethyl)-porphyrin-yl]-pyridine(3)and 4,4′-di-[5,10,15-triphenyl-20-(p-phenoxycarbonyl)-porphyrin-yl]-2,2′-bipyridine(4).5-[4-(4′-Bromobutoxy)phenyl]-10,15,20-triphenyl porphyrin reacted with 2,6-dihydroxymethylpyridine to give 2,6-bis-[5,10,15-triphenyl-20-(4-(p-phenoxy)-butoxymethyl)-porphyrin-yl]-pyridine(5).Those new compounds have been identified by1H NMR,IR,MS and UV-visible spectra,and elemental analysis. 展开更多
关键词 bridged porphyrin synthesis structure characterization
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