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大环化合物(macrocycles)酶模型
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作者 黄峙 郭宝江 李学梅 《广州化学》 CAS 1999年第3期61-64,共4页
对大环化合物的结构特点及催化作用进行了综述。
关键词 大环化合物 酶模型 催化作用 模型化合物
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Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring 被引量:1
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作者 Chang Rong NIU Hai Ning ZHANG Cheng Tai WU(Department of Chemistry, Wuhan University, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期569-572,共4页
A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines.... A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines. The chemical structures of the new compounds were characterized by elemental analysis, infrared spectra, nuclear magnetic resonance spectra and mass spectrometry. 展开更多
关键词 OCH IR CM KBR HNMR Synthesis of Schiff Base Type macrocycles Containing Naphthalene Ring
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Synthesis of Novel C_2-Symmetric Chiral Polyamide Macrocycles Containing Pyridyl Side-arm
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作者 XiaoCHEN DaMingDU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第11期1037-1038,共2页
Three novel C2-symmetric macrocycles containing pyridyl units have been prepared by the cyclic condensation of chiral diamide intermediates with 2,6-pyridinedicarbonyl dichloride in highly diluted solution at room tem... Three novel C2-symmetric macrocycles containing pyridyl units have been prepared by the cyclic condensation of chiral diamide intermediates with 2,6-pyridinedicarbonyl dichloride in highly diluted solution at room temperature. 展开更多
关键词 Synthesis macrocycles CHIRAL pyridine.
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Synthesis and Electrical Conductivities of Fully Conjugated Schiff Base Macrocycles Containing 1,3,4-Oxadiazole
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作者 Shu WANG Wen Ting HUA Zhi Tao LI(Department of Chemistry, Peking University. Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第5期367-370,共4页
Conjugated Schiff base macrocycles containing 1,3,3-oxadiazole were prepared by [2 + 2] cyclic condensation of phenylenediamine with 2,5-bis(m-formyl-phenyl)-1,3,4-oxadiazole. These macrocycles with iodine or TCNQ pro... Conjugated Schiff base macrocycles containing 1,3,3-oxadiazole were prepared by [2 + 2] cyclic condensation of phenylenediamine with 2,5-bis(m-formyl-phenyl)-1,3,4-oxadiazole. These macrocycles with iodine or TCNQ produced stable charge-transfer complexes. The formation of complexes were identified by UV-Vis and FT-IR spectra. 展开更多
关键词 conjugated Schiff base macrocycles SYNTHESIS charge-transfer complexes
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Synthesis of phosphorus-containing polyoxamacrocycles with one to two reactive thiophosphoryl chloride groups
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作者 Xiao Mei Zhang Dao Quan Wang Wan Yi Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第5期553-555,共3页
Novel phosphorus-containing polyoxamacrocycles with one to two reactive thiophosphoryl chloride groups 5, 6, 7, 8 were synthesized from bishydroxyl compounds 1, 2, 3, 4 and thiophosphoryl chloride respectively. Their ... Novel phosphorus-containing polyoxamacrocycles with one to two reactive thiophosphoryl chloride groups 5, 6, 7, 8 were synthesized from bishydroxyl compounds 1, 2, 3, 4 and thiophosphoryl chloride respectively. Their structures were confirmed by ^ 1H NMR, ^13C NMR, ^31p NMR and elemental analysis. 展开更多
关键词 Phosphorus-containing macrocycle Phosphorus-containing polyoxamacrocycle Thiophosphoryl chloride cyclization
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Synthesis and Mesophase Properties of Intraanular Functionized Shape-persistent Macrocycles Containing Dibenzo[fg,op]naphthacenes
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作者 CHENG Xiao-hong HOEGER Sigurd 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第1期35-43,共9页
On the basis of the C-C coupling reactions of dibenzo [ fg, op ] naphthacene bistriflate, which was obtained by the condensation of phenylacetates with 4-aryl-2,6-bis(2-bromo-4-methoxy-phenyl) pyrylium salts followe... On the basis of the C-C coupling reactions of dibenzo [ fg, op ] naphthacene bistriflate, which was obtained by the condensation of phenylacetates with 4-aryl-2,6-bis(2-bromo-4-methoxy-phenyl) pyrylium salts followed by palladium-catalyzed dehydrohalogenation, three shape-persistent macrocycles with dibenzonaphthacene corner pieces, a nanometer interior void, and intraanular oligoalkyl side groups were synthesized by the oxidative cyclization of the corresponding bisacetylenes under high-dilution conditions. Their thermotropic liquid crystalline properties were investigated by using polarizing microscopy and differential scanning calorimetry. All the three compounds showed nematic mesophases and belonged to discotic liquid crystals with inverted topology. 展开更多
关键词 Dibenzo [ fg op ] naphthacene macrocycles Liquid crystal C-C coupling
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Construction of a Self-assembling Intertwined Spiral Solvent Channel Based on Interactions between Macrocycles and CH_2Cl_2
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作者 庞韬 吴雪 +4 位作者 吴奎 付晨 刘涛 武琳 吴根华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第10期1737-1742,共6页
The construction of an unprecedented intertwined spiral solvent channel is driven by weak C–Cl…O and C–H…N interactions based on extraordinary parallel spirals which were structured from supramolecular synthon mac... The construction of an unprecedented intertwined spiral solvent channel is driven by weak C–Cl…O and C–H…N interactions based on extraordinary parallel spirals which were structured from supramolecular synthon macrocycle 1(C44H44N4O4) with a propargylamine backbone. The product is characterized by ^1H NMR, ^13C NMR, IR and HRMS, and further confirmed by single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C2/c, with a = 28.922(3), b = 8.5069(9), c = 21.687(2)A^°, β = 130.6320(10)°, V = 4049.4(7) A^°3 and Z = 8. A total of 11874 reflections were collected, of which 4942 were independent(Rint = 0.0590) and 2937 were observed with I 〉 2σ(I). The final full-matrix least-squares refinement gave R(I 〉 2s(I)) = 0.069 and w R = 0.167, S = 1.05,(Δρ)max = 0.20 and(Δρ)min =-0.22 e·A^1-3. The fluorescence of the product is discussed. 展开更多
关键词 intertwined spiral solvent channel PROPARGYLAMINE supramolecular synthon macrocycle crystal
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THE SYNTHESIS AND CHARACTERIZATION OF ASYMMETRIC TRIPYRRANE-CONTAINING MACROCYCLES
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作者 Shi Ming DONG Hui Zhu HE Lin Zhi HU Jian Min RON Duo Yuan WANG Jnstitute of Photogrsphic Chemistry,Academia Sinica,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期19-22,共4页
An improved procedure was used to prepare the asymmetric tripyrrane-containing macrocycles, The yield was over 85% These maerocycles could be oxidized to the methine bridled 23 (?)-electron aromatic cadmium(Ⅱ)complex... An improved procedure was used to prepare the asymmetric tripyrrane-containing macrocycles, The yield was over 85% These maerocycles could be oxidized to the methine bridled 23 (?)-electron aromatic cadmium(Ⅱ)complexes by reating with cadmium chloride in the presence of air and their atructures were characterized. 展开更多
关键词 CB IR Br Cl der UV THE SYNTHESIS AND CHARACTERIZATION OF ASYMMETRIC TRIPYRRANE-CONTAINING macrocycles
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PHOTOPHYSICAL PROPERTIES OF THE ASYMMETRIC PENTAAZADENTATE PORPHYRIN-LIKE MACROCYCLES
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作者 Shi Ming DONG Duo Yuan WANG Institute of Photographic Chemistry,Academia Sinica,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第6期507-510,共4页
The porphyrin-like macrocycles and their metal complexes are s novel family of photoresponsive molecules.The properties of the excited states,both singlet and triplet are investigated by the stationary and transient p... The porphyrin-like macrocycles and their metal complexes are s novel family of photoresponsive molecules.The properties of the excited states,both singlet and triplet are investigated by the stationary and transient processes. 展开更多
关键词 TXP CI PHOTOPHYSICAL PROPERTIES OF THE ASYMMETRIC PENTAAZADENTATE PORPHYRIN-LIKE macrocycles Cd
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SYNTHESIS OF AZA-OXA MACROCYCLES CONTAINING PYRIDINE RING
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作者 Guo Ping XUE Cheng Tai WU(Department of Chemistry, Wuhan University. Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第1期19-22,共4页
A new type of aza-oxa macrocycles containing pyridine ring which may be used for binding of prinary ammonium cations(R-NH) were prepared from 2.6-di(bromomethyl) pyridine and appropriate diol.
关键词 OXA SYNTHESIS OF AZA-OXA macrocycles CONTAINING PYRIDINE RING
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Synthesis of Macrocycles Containing Amino Acid Ester and Aryl-heterocyclic Units
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作者 Yan Tao CHEN Wen Ting HUA Qi Yi XING(Department of Chemistry Peking University Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,0-0,共4页
Four kinds of new macrocycles containing amino acids and nyl-heterocyclic units were synthesized by the condensation of di-esters containing Ts-amino acids units with di-halogenated compounds at room temperature. The ... Four kinds of new macrocycles containing amino acids and nyl-heterocyclic units were synthesized by the condensation of di-esters containing Ts-amino acids units with di-halogenated compounds at room temperature. The macrocycles were characterized by elemental analysis, IR,MS(FAB) and 1H NMR 展开更多
关键词 FAB Synthesis of macrocycles Containing Amino Acid Ester and Aryl-heterocyclic Units
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Studies on the Protonation and Complexations of Dioxotetraamine Macrocycles
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作者 Wan Dong CHEN Xiang Chen YIN +4 位作者 Shou Rong ZHUa Hua Kuan LIN Appolin Bave KONDIANO Mei Rong LIN and Yun Ti CHEN (Department of Chemistry.Nankai University,Tianjin 300071)(Department of Chemistry,Jining Teacher’s College,Jining 272125)(Institute of Modern Op 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第9期864-867,共4页
14-Membered macrocyclic dioxotetraamines deprotonate stepwisely upon coordination to cupric ions. Singly- and doubly-deprotonated complexes are the main species, While for 13-membered analogs, non- and doubly-deproton... 14-Membered macrocyclic dioxotetraamines deprotonate stepwisely upon coordination to cupric ions. Singly- and doubly-deprotonated complexes are the main species, While for 13-membered analogs, non- and doubly-deprotonated complexes are the main species. 展开更多
关键词 Studies on the Protonation and Complexations of Dioxotetraamine macrocycles
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Structural characterization and mass spectrometry fragmentation signatures of macrocyclic alkanes isolated from a Sydney Basin torbanite,Australia
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作者 Xianxin Meng Hong Lu +2 位作者 Zhirong Zhang Ping’an Peng John K.Volkman 《Acta Geochimica》 EI CAS CSCD 2023年第3期488-494,共7页
Individual hydrocarbons identified to be macrocyclic alkanes in a torbanite from the Sydney Basin(Australia)were successfully isolated from its extracts using preparative gas chromatography and analyzed by NMR.Saturat... Individual hydrocarbons identified to be macrocyclic alkanes in a torbanite from the Sydney Basin(Australia)were successfully isolated from its extracts using preparative gas chromatography and analyzed by NMR.Saturated cyclic structures were confirmed by single peaks in the NMR~1H and~(13)C spectra indicating single forms of H and C atoms exist in these biomarker molecules.This is consistent with the methylene unit in a ring system assignment of the macrocyclic alkanes and accounts for a formula of(CH2)n.The unusual molecular structures of these compounds are consistent with those that were identified from previous GC retention index data and co-injection with a standard supports the previous research.The mass spectral fragmentation behaviors of representative cyclic alkanes were further investigated by comparing them with the mass spectra of isolated individual macrocyclic alkanes.The characteristic fragment ions in the macrocyclic alkanes of(M–28)+and base peaks of m/z 97,111,125,etc.,can be assigned as being generated by simple a-/i-cleavage and hydrogen rearrangement.These fragmentation pathways combined with retention indices should assist in differentiating these compounds from monounsaturated alkenes and alkylated monocyclics having similar mass spectral characteristics in other geological samples. 展开更多
关键词 macrocyclic alkanes Torbanite NMR Preparative GC MS fragmentation
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基于半夹心Cp*Rh单元的超分子桥环和螺环化合物的构筑策略
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作者 高翔 牟秋水 +1 位作者 林悦健 金国新 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期164-172,共9页
桥环和螺环化合物是有机化学中常用的概念而在其他领域鲜有提及。在本研究中,我们将桥环和螺环的概念拓展至超分子化学领域中并提出了相应的构筑策略。在刚性直线型配体中引入额外的螯合位点,通过配位驱动、分步组装的方法合成了复杂的... 桥环和螺环化合物是有机化学中常用的概念而在其他领域鲜有提及。在本研究中,我们将桥环和螺环的概念拓展至超分子化学领域中并提出了相应的构筑策略。在刚性直线型配体中引入额外的螯合位点,通过配位驱动、分步组装的方法合成了复杂的3个有机金属超分子桥环化合物[(Cp*Rh)_(6)(μ-η^(2)-η^(2)-C_(2)O_(4))_(2)(μ-C_(2)O_(4))(L^(A))_(2)](OTf)_(6)(1)、[(Cp*Rh)_(6)(dhbq)_(2)(pyrazine)(L^(A))_(2)](OTf)_8(2)和[(Cp*Rh)_(6)(tpphz)_(2)(bpea)(L^(A))_(2)](OTf)_(12)(3),以及一个超分子螺环化合物(Cp*Rh)_(12)(bibzim)_(3)Ru(L^(A))_(3)(L^(B))_(3)](OTf)_(10)(PF_(6))_(4)(4),其中L^(A)=3,3'-di(pyridin-4-yl)-2,2'-bipyridine,OTf^(-)=CF_(3)SO_(3)^(-),dhbq=2,5-dihydroxy-1,4-benzoquinone,tpphz=tetrapyrido[3,2-a∶2',3'-c∶3″,2″-h∶2′″,3′″-j]phenazine,bpea=1,2-di(pyridin-4-yl)ethane,bibzim=2,2'-bisbenzimidazole,L^(B)=4,4'-di(pyridin-4-yl)-1,1'-biphenyl。并通过单晶X射线衍射的方法一一表征了它们的单晶结构。 展开更多
关键词 自组装 大环 配位驱动 桥环化合物 螺环化合物
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Synthesis and applications of lanthanoid complexes of pentadentate and hexadentate N_(5) and N_(6) macrocycles:A review 被引量:2
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作者 Julio Corredoira-Vázquez Cristina González-Barreira +3 位作者 Paula Oreiro-Martínez Ana M.García-Deibe Jesús Sanmartín-Matalobos Matilde Fondo 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第1期1-15,I0001,共16页
In this paper,the lanthanoid complexes of N_(5) and N_(6) macrocycle ligands,without pendant arms or additional heteroatoms,are surveyed.This review covers the period from 2015 to the current date,since in 2014 Schiff... In this paper,the lanthanoid complexes of N_(5) and N_(6) macrocycle ligands,without pendant arms or additional heteroatoms,are surveyed.This review covers the period from 2015 to the current date,since in 2014 Schiff base macrocyclic ligands incorporating the pyridine moiety,and their complexes,were revised,and in 2015 the chemistry of pentaaza macrocycle ligands with rare earth metals was also summarized.Porphyrin and phthalocyanine ligands are not included in this review,which primarily focuses on complexes with Schiff bases and amines without pendant arms or any additional donor other than nitrogen.The synthetic methods,structural characterization,based on single X-ray crystal data,and properties of the lanthanoid complexes,with special attention to magneto-structural correlations,are presented herein. 展开更多
关键词 LANTHANOID N_(5) N_(6)macrocycle Coordination chemistry CHIRALITY Biological activity Molecule magnet
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以Tröger碱大环为例分析多手性中心大环的立体异构体
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作者 石聪浩 王冉冉 +1 位作者 强琚莉 王乐勇 《大学化学》 CAS 2024年第7期394-397,共4页
立体异构现象是有机化学中重要的异构现象之一,具有重要的研究和教学意义。本文将以Tröger碱单元构筑的超分子大环为例,结合实验结果,探讨具有多手性中心大环的立体异构体。
关键词 立体异构体 手性大环 Tröger碱
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基于残留偶极耦合对西松烷二萜化合物sinulariol Z立体化学的研究
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作者 石星 张越 +1 位作者 张秀丽 王聪 《波谱学杂志》 CAS 2024年第3期322-330,共9页
天然产物的立体化学研究,特别是柔性大环分子化合物的立体化学问题,一直是相关领域面临的巨大难题.西松烷二萜类化合物是一类典型的柔性大环分子化合物,采用耦合常数(Coupling constant)和NOE(Nuclear Overhauser effect)效应两种局部... 天然产物的立体化学研究,特别是柔性大环分子化合物的立体化学问题,一直是相关领域面临的巨大难题.西松烷二萜类化合物是一类典型的柔性大环分子化合物,采用耦合常数(Coupling constant)和NOE(Nuclear Overhauser effect)效应两种局部特性核磁共振参数来确定该类化合物立体构型是最常用的方法之一.残留偶极耦合(Residual dipolar coupling,RDC)和量子化学计算等方法的发展进一步丰富了解决立体化学问题的手段.其中,RDC作为一种非局部特性核磁共振参数,不仅被多次报道应用于蛋白质、核酸等生物分子的结构构建及功能研究,也逐渐被应用于许多天然产物分子的立体构型确定,在药物分子构型研究方面做出了突出贡献.目前,RDC在西松烷二萜类化合物的立体构型确定方面的研究报道较少.本文首次采用RDC参数探索西松烷二萜类化合物sinulariol Z的立体化学构型问题,并结合单晶X射线衍射法,对sinulariol Z的立体构型进行了再次确证,进一步验证了RDC参数在西松烷二萜类化合物立体化学研究中的可行性. 展开更多
关键词 残留偶极耦合参数 西松烷二萜 立体化学 柔性大环分子 天然产物
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多次注射钆对比剂后小脑齿状核T1WI信号变化的研究
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作者 郗艳 邓小飞 舒政 《中国CT和MRI杂志》 2024年第11期11-13,36,共4页
目的测量统计多次使用钆对比剂后小脑齿状核平扫T1WI上的信号变化,探索多次钆对比剂使用对钆脑沉积的影响。方法搜集2013.6-2023.6行4次及以上的MRI增强的患者153例,线性-钆喷酸葡胺组122例,大环-钆特醇31例,选择第1次和末次平扫T1WI,... 目的测量统计多次使用钆对比剂后小脑齿状核平扫T1WI上的信号变化,探索多次钆对比剂使用对钆脑沉积的影响。方法搜集2013.6-2023.6行4次及以上的MRI增强的患者153例,线性-钆喷酸葡胺组122例,大环-钆特醇31例,选择第1次和末次平扫T1WI,结局事件为增强后齿状核信号的增高。记录患者年龄、性别、对比剂使用次数和间隔、疾病类型等临床特征,使用Logistic回归分析与齿状核信号增高的相关的因素。结果在153例患者中,男:女=68:85,平均56.58±14.50岁,平均接受6±4次注射,平均间隔4.25±3.77月,69例(45.1%)被观察到小脑齿状核信号增高,均发生于线性钆对比剂组。齿状核信号增高还与线性钆使用次数呈正相关(B=1.57,OR=4.82,P<0.01),与增强时间间隔呈负相关(B=-0.72,OR=0.49,P<0.01),但与其它特征无关(P>0.05)。结论小脑齿状核T1WI信号增高与线性钆对比剂注射次数和时间间隔有关,但与大环钆的使用无关。 展开更多
关键词 齿状核 磁共振成像 钆对比剂 线性 大环
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基于斜塔芳烃的晶体工程研究
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作者 吴佳睿 吴庚辛 +1 位作者 王艳 杨英威 《大学化学》 CAS 2024年第3期58-62,共5页
凭借固有的分子识别和络合能力,大环主体分子一直是超分子化学研究所依赖的重要工具,同时也大力地推动了现代超分子化学的蓬勃发展并从基础研究走向实际应用。斜塔芳烃做为一类新型芳烃大环受体具有易溶解、易结晶、良好的骨架柔性和主... 凭借固有的分子识别和络合能力,大环主体分子一直是超分子化学研究所依赖的重要工具,同时也大力地推动了现代超分子化学的蓬勃发展并从基础研究走向实际应用。斜塔芳烃做为一类新型芳烃大环受体具有易溶解、易结晶、良好的骨架柔性和主客体化学性质等特点和优势,自其诞生以来便在晶体工程和相关研究领域得到广泛应用和发展。本文将从晶体工程角度出发来介绍若干有关斜塔芳烃的应用研究实例,重点突出结构与功能之间的内在关联,以期提高学生对晶体化学及其交叉学科的学习兴趣和内在驱动力。 展开更多
关键词 晶体工程 超分子化学 大环化学 主客体化学
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金属卡宾模板导向的多咪唑鎓盐大环合成
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作者 王以寿 白莎 +1 位作者 王尧宇 韩英锋 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期221-231,共11页
本文报道了一种共价有机大环化合物的高效合成方法。利用双咪唑鎓盐H_(2)‐L1(BF_(4))_(2)(L1=A1,B1)和氧化银反应,生成双核银卡宾大环化合物[Ag_(2)(L1)_(2)](BF_(4))_(2)(L1=A1,B1),其中连接在2个卡宾配体上的端烯取代基分别排列在环... 本文报道了一种共价有机大环化合物的高效合成方法。利用双咪唑鎓盐H_(2)‐L1(BF_(4))_(2)(L1=A1,B1)和氧化银反应,生成双核银卡宾大环化合物[Ag_(2)(L1)_(2)](BF_(4))_(2)(L1=A1,B1),其中连接在2个卡宾配体上的端烯取代基分别排列在环的两侧。随后,通过金属卡宾模板导向的烯烃复分解反应进行关环,制备得到闭环的双核银卡宾大环化合物[Ag_(2)(L2)](BF_(4))_(2)(L2=A2,B2)。最后,移除模板银离子即可得到拥有空腔结构的共价有机大环化合物H_(4)-L2(BF_(4))_(4)(L2=A2,B2)。此类多咪唑鎓盐大环的尺寸和形状可以通过改变氮杂环卡宾前驱体连接单元的长度或者宽度进行精细调节。初步研究表明,该大环受体在碘离子的传感、检测和识别方面具有潜在的应用前景。 展开更多
关键词 模版导向合成 大环化合物 氮杂环卡宾 烯烃复分解反应
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