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Distorted aryl homochirality controlled byβ-sheet folding

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Chinese Chemical Letters 2023年第11期34卷 147-152页

作者： Yunying Xu aiyou hao Pengyao Xing School of Chemistry and Chemical Engineering Shandong UniversityJi’nan 250100China

Distortion of planar aromatics occurs in the fused rings conjugated with bulky substituents,which generates racemic enantiomers with high transformation energy ***,direct synthesis of homochiral distorted aryl compounds is a very challenging ***,we presented a molecular folding strategy to control distorted aryl *** acids and their derivatives conjugated on the polycyclic aromatic hydrocarbons including benzenes,naphthalenes and triphenylenes,which formed parallelβ-sheet arrays through intramolecular hydrogen *** folding behavior enabled distorted or twisted geometry of aromatics,of which the handedness was associated with the absolute chirality of amino acids.X-ray crystallography,theoretical calculations and circular dichroism spectroscopy verified the distorted homochirality in the solid and solution *** relatively small rotational barrier between the enantiomers made the molecule sensitive to the environment and thus realized the solvent-controlled chiral ***β-sheet folding strategy can be widely used in polycyclic aromatic hydrocarbons with various functions,which provided a promising strategy to control inherent chirality of aromatics with adaptive chiroptical responses.

关键词： Distorted chirality Folding Solvent strategy Chiroptical activity

Fmoc-protected amino acids as luminescent and circularly polarized luminescence materials based on charge transfer interaction

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Chinese Chemical Letters 2022年第11期33卷 4918-4923页

作者： Yiran Xia aiyou hao Pengyao Xing Key Laboratory of Colloid and Interface Chemistry of Ministry of Education and School of Chemistry and Chemical Engineering Shandong UniversityJi'nan 250100China

Fluorenylmethyloxycarbonyl(Fmoc)-protected amino acids are effective building blocks in self-assembled architectures at hierarchical levels,which however show limited luminescent properties and chiroptical *** we introduce a charge-transfer strategy to build two-component luminescent materials with emerged circularly polarized luminescence properties.A library of Fmoc-amino acids was built,which selectively form charge-transfer complexes with the electron-deficient *** in amorphous polymer matrix or physical grinding could trigger the charge-transfer luminescence with adjusted wavelengths in a general manner.X-ray diffraction results suggest the multiple binding modes between donor and ***,the solution-processed coassembly could selectively exhibit circularly polarized luminescence with high dissymmetry *** work illustrates a noncovalent charge-transfer strategy to construct luminescent and chiroptical organic composites based on the easy-accessible and economic chiral N-terminal aromatic amino acids.

关键词： Fmoc-amino acids Charge-transfer interaction Supramolecular chirality Multiple component coassembly

Helical secondary structures and supramolecular tilted chirality in N-terminal aryl amino acids with diversified optical activities

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Chinese Chemical Letters 2021年第4期32卷 1390-1396页

作者： Zhuoer Wang aiyou hao Pengyao Xing School of Chemistry and Chemical Engineering Shandong UniversityJi'nan 250100China

Helix structures at atomic/molecular level have not been found in self-assembled peptide seque nce with less than three ***β-sheet supramolecular secondary structures have been discovered in solidstate amino acids,we here report the conjugation of simple N-terminal aryl protecting group could give rise to helical supramolecular secondary structures in solid-state,which determines the optical activities of the adjacent aryl *** carboxylic acid-involved asymmetric H-bonds in N-te rminal aryl amino acids induce the emergence of super-helical structures of amino acid residues and aryl *** most cases,supramolecular tilted chirality of aryl groups is opposite to that of amino acid sequences,of which handedness and helical pitch are determined by the H-bond *** correlation between supramolecular tilted chirality of aryl segments and their chiroptical activities is firstly unveiled,which was verified by the computational results based on density functional *** aryl amino acids self-assembled by nanoprecipitation method via crystallization induced self-assembly into rigid one-dimensional microstructures with ultra-high Young's *** study reveals the generic existence of chiral supramolecular structure s in aggregated amino acid derivatives and gives an in-depth investigation into the structural-property relationships,which could guide the rational design and screening of chiroptical supramolecular materials.

关键词： Amino acids Self-assembly Chirality Chiroptical properties H-bonds

Guest-adaptive chiral coassembly of a conformationally locked host into supramolecular boxes and ladders through arene-perfluoroarene force

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Science China Chemistry 2024年第10期67卷 3482-3492页

作者： Weilong Ma Xinyi Li aiyou hao Pengyao Xing School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100China

Unveiling the role of weak non-covalent forces in chiral self-assembly is pivotal in the design and fabrication of functional chiroptical *** nature of arene-perfluoroarene(AP)force is the electrostatic attraction betweenπ-hole andπplanes of perfluoroarenes and polyaromatic hydrocarbons(PAHs),which is emerging in constructing supramolecular motifs and coassembled optical *** this work,we reveal the potential of AP forces in building diversified levels of chiral coassemblies adaptive to the geometries of *** naphthalene-F8was covalently conjugated with a chiral amine,which folded into a semi-rectangular geometry via two intramolecular F···H *** of naphthalene,anthracene,pyrene,carbazole,perylene and benzoperylene were introduced to afford coassemblies in the crystalline state.X-ray structures suggest the formation of supramolecular boxes that encapsulate the PAHs with a 2:1 stoichiometric ratio,as well as the formation of consecutive layered ladders with a 1:1 stoichiometric *** preference is adaptive to the geometries of PAHs,and experimental and computational results evidenced the ladder structures possess strong binding *** this top,the selective chiral recognition in the mixtures of PAHs was realized,which shows promising applications in the separation of PAHs and rational design of crystalline chiroptical materials.

关键词： arene-perfluoroarene force coassembly supramolecular chirality selectivity

Chiroptical coassemblies between organic carboxylic acids and amino acid derivatives with C_(3)-symmetry

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Chinese Chemical Letters 2023年第6期34卷 319-322页

作者： Yiran Xia aiyou hao Pengyao Xing School of Chemistry and Chemical Engineering Shandong UniversityJi’nan 250100China

Benzimidazole amino acid derivatives behave as supramolecular hosts to include organic acids via complementary hydrogen bonding whereby supramolecular chirality and chiroptical properties could be *** acids enhanced the chiral assembly that showed tunable circularly polarized luminescence with high dissymmetry g-factors at 10^(-2)grade.

关键词： Supramolecular chirality Organic carboxylic acid Amino acid Coassembly Chiroptical property

Gas phase ethylene polymerization over SiO_(2)-supported organosilyl chromate UCC S-2 catalyst using a high-speed stirred-autoclave reactor

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Frontiers of Chemical Science and Engineering 2011年第1期5卷 89-95页

作者： Liuzhong LI aiyou hao Ruihua CHENG Boping LIU School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100China State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Research Institute of Qilu Branch Co. SINOPECZibo 255400China

Although an important industrial catalyst for producing high density polyethylene,the SiO_(2)-supported organosilyl chromate UCC S-2 catalyst has not been fully investigated compared with the SiO_(2)-supported oxo chromium Phillips *** this work,gas phase ethylene polymerization by S-2 catalysts(Cat-1,Cat-2,and Cat-3)was carried out in a high-speed stirredautoclave *** effects of temperature,time,and pressure on kinetics,activity,and product properties were *** kinetics were typical built-up types with slow *** to the simple physical mixtures of Cat-1 and Cat-2,Cat-3 showed higher activity and its product had a broader molecular weight distribution,indicating new active species induced during blending of Cat-1 and Cat-2 in *** innovation by a simple catalyst technology created a new application to meet market demands.

关键词： UCC S-2 catalyst Al-alkyl co-catalyst gasphase ethylene polymerization high density polyethylene

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用环糊精合成楔筒状主体分子新模型

化学学报 2002年第8期60卷 1536-1538页

作者：郝爱友王金山山东大学化学与化工学院济南250100 山东师范大学化学系济南250014

用四醋酸铅将七元 (6 O 二甲基叔丁基硅基 ) β 环糊精选择氧化、并用三氟化硼乙醚脱硅基保护基后 ,再经分离、纯化 ,可获得具有“楔筒状”空腔的单 2 ,3 二醛基 β 环糊精 .单 2 ,3 二醛基 β 环糊精较 β 环糊精有更好的水溶性 ... 详细信息

用四醋酸铅将七元 (6 O 二甲基叔丁基硅基 ) β 环糊精选择氧化、并用三氟化硼乙醚脱硅基保护基后 ,再经分离、纯化 ,可获得具有“楔筒状”空腔的单 2 ,3 二醛基 β 环糊精 .单 2 ,3 二醛基 β 环糊精较 β 环糊精有更好的水溶性 .用单 2 ,3 二醛基 β 环糊精作TLC流动相手性添加剂时 ,可将肾上腺素对映体在硅胶薄层板上有效拆分 .

关键词：主体分子 β-环糊精单-2,3-二醛基-β-环糊精楔筒状大环分子主客体化学

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环糊精-石墨烯超分子体系

有机化学 2012年第11期32卷 2054-2062页

作者：孙涛李建业郝爱友山东大学化学与化工学院济南250100 潍坊科技学院潍坊262700

环糊精是由D型吡喃葡萄糖通过α-1,4-糖苷键连接而成的环状超分子主体化合物,其特殊的结构赋予了其良好的分子识别性能;石墨烯是仅由单层sp杂化的碳原子构筑的具有良好的电化学性能的材料.作为著名的"明星分子",石墨烯类材料无疑是近5... 详细信息

环糊精是由D型吡喃葡萄糖通过α-1,4-糖苷键连接而成的环状超分子主体化合物,其特殊的结构赋予了其良好的分子识别性能;石墨烯是仅由单层sp杂化的碳原子构筑的具有良好的电化学性能的材料.作为著名的"明星分子",石墨烯类材料无疑是近5年来研究热点之一.在各种各样的石墨烯材料中,由环糊精-石墨烯联合构筑的超分子体系在保留二者优良性能的同时又引入了新的功能特点.综述了近些年来新发展起来的环糊精-石墨烯超分子体系:通过二者作用方式进行了分类,分为共价键连接和非共价键连接;综述了该超分子体系在药物运输及释放、电化学检测(包括对药物分子、污染物和生物分子的检测)等领域的应用;最后对该体系在药物负载及释放、模拟生物固氮、燃料电池、研究电子传导等应用前景进行了展望.

关键词：环糊精石墨烯超分子化学药物运输电化学检测

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多组分手性超分子的构筑及其应用

科学通报 2021年第14期66卷 1666-1677页

作者：成秋鸿郝爱友邢鹏遥山东大学化学与化工学院济南250100

手性与生命现象密切相关,如氨基酸、蛋白质和核酸的手性结构,以及宏观的海螺等.分子模块的不对称性堆积称为超分子手性.对超分子手性的出现、放大、转移以及反转的调控是超分子手性中几个重要的研究方向.超分子手性组装体通常由多种非... 详细信息

手性与生命现象密切相关,如氨基酸、蛋白质和核酸的手性结构,以及宏观的海螺等.分子模块的不对称性堆积称为超分子手性.对超分子手性的出现、放大、转移以及反转的调控是超分子手性中几个重要的研究方向.超分子手性组装体通常由多种非共价相互作用协同驱动形成,是一类具有独特手性微环境的软物质.其中,含两种或两种以上组分的超分子组装体既可能经过协同组装作用也可能发生自分类.其存在多种组装路径,相对于单组分体系复杂得多.因此,与发展更为成熟的单组分体系相比,多组分超分子手性组装体在基础和应用方面的研究都受到了限制.然而,研究多组分中的超分子手性既可以模拟复杂的手性生物体系,也可以加深对自然界中手性起源的理解,从而进一步应用于仿生学和手性材料,具有重要的意义.因此本文主要对多组分手性超分子共组装体系的构建以及可能的应用进行了综述和总结.

关键词：超分子手性多组分自组装手性调控圆偏振发光