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ESIPT-regulated Mechanoresponsive Luminescence Process by Introducing intramolecular hydrogen bond in Naphthalimide Derivatives

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Chemical Research in Chinese Universities 2022年第4期38卷 1050-1056页

作者： ZHANG Bingyi ZHANG Xiaole SU Ruochen SUN Yue DUAN Lian School of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan030024P.R.China

Herein,two compounds,4-2′-hydroxybenzylidenehydrazinyl-N-butyl-1,8-naphthalimide(BN-1)and 4-benzylidenehydrazinyl-N-butyl-1,8-naphthalimide(BN-2),were synthesized to explore the hydrogen bonding effect on mechanoresponsive luminescent(MRL).The results showed that compound BN-1 exhibited strong emission in solution and solid-state compared with compound *** grinding,the emission intensity of compound BN-1 sharply decreased by as much as 15 times with an obvious red-shift from 552 nm to 577 *** control compound BN-2,by contrast,did not change so much before and after *** crystal analysis suggests that BN-1 molecule formed strong intramolecular interaction via-N=N⋯H-O hydrogen bond with a distance of 0.2632 *** excited-state intramolecular proton transfer(ESIPT)based fluorophore featured this intramolecular hydrogen *** intramolecular hydrogen bond as well as other intermolecular interactions can rigidify the molecular conformation of compound BN-1 in solid-state,and thus suppress the nonradiative pathways,resulting in strong *** intra-and intermolecular interactions were destroyed by mechanical stimuli,accompanied by molecular conformation change that decreases the luminescence and blocks the ESIPT *** MRL process was also demonstrated by scanning electron microscopy and powder X-ray *** molecular stacking mode changed from crystalline to a disordered amorphous state after grinding.

关键词： Naphthalimide derivative Mechanoresponsive luminescence intramolecular hydrogen bond

Synthesis and Theoretical Study of intramolecular hydrogen bond at Two Possible Positions in Pyrazolo[1,2-b]phthalazine

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Chinese Journal of Chemistry 2012年第4期30卷 779-784页

作者： Yoosefian,M. Raissi,H. Davamdar,E. Esmaeili,A.A. Azaroon,M. Chemistry Department Birjand UniversityBirjandIran Chemistry Department Siastan and Balouchestan UniversityZahedanIran

Properties of dimethyl 3-（alkylamino）-5,10-dioxo-5,10-dihydro-1H-pyraolo[1,20b]phthalazine-1,2-dicarboxy-late and its derivatives were studied by means of ab initio method. NO2 derivative of title compound was synthe- sized and the nature of its intramolecular hydrogen bond （HB） was investigated. Furthermore, the topological prop- erties of the electron density distributions for N--H＇＂O intramolecular bridges were analyzed in terms of the Bader theory of atoms in molecules （AIM）. The electron density （p） and Laplacian （V2p） properties, estimated by AIM calculations, indicated that O＇--H bond possesses low P and positive VZp values which are in agreement with elec- trostatic character of the HBs, whereas N--H bonds have covalent character （V2p〈0）. Moreover, steric effect of the t-Bu group on structure and topological parameters of pyrazolo[1,2-b]phthalazine conformers was studied. Fi- nally, the powerful method of Espinosa was used to obtain the H-bond energy.

关键词： pyrazolo[ 1,2-b]phthalazine intramolecular hydrogen bond charge density

Density Functional Theoretical Studies on Effect of intramolecular hydrogen bonds on Reduction of Nitrophenols

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Chemical Research in Chinese Universities 2017年第5期33卷 785-793页

作者： ZHANG Hongmei LIU Yan MA Fangping QIU Wei LEI Bo SHEN Jinyou SUN Xiuyun HAN Weiqing LI Jiansheng WANG Lianjun Jiangsu Key Laboratory for Chemical Pollution Control and Resource Reuse School of Environmental and Biological Engineering Nanjing University of Science and Technology Nanjing 210094 P. R. China Chuannan Machinery Factory China Aerospace Science and Technology Corporation Luzhou 646000 P. R. China

intramolecular hydrogen bonds（IMHBs） can lead to different physicochemical characteristics of nitro- phenols（NPs） that determine their environmental behavior. In the present work, to reveal the relationship between IMHB and nitrophenol reduction, the effects of IMHB on the molecular geometries and properties of a series of ni- trophenols were investigated with density functional theory（DFT） calculations. The results of the geometry optimiza- tion and atoms-in-molecules（AIM） analysis indicate relatively strong IMHBs in ortho-substituted nitrophenols, whose stability could be significantly improved. In comparing the ELUMO and adiabatic electron affinities（AEA） of the nitrophenol isomers, the presence of IMHBs benefited the reductive degradation of NPs, consistent with a previous study. To gain an insight into the effect mechanism of IMHBs on the reductive degradation behavior of these mole- cules, the condensed electrophilicity Fukui index（f-）, natural charges and Wiberg bond orders of these nitrophenol isomers were calculated. The calculations indicate that the electrophilic reactivity activity of the O atom on the nitro group could be significantly improved due to the formation of IMHBs, which results in the enhanced reductive degradation of ortho-substituted NPs.

关键词： Nitrophenol Reduction intramolecular hydrogen bond Effect mechanism Density functional theory

Installing hydrogen bonds as a general strategy to control viscosity sensitivity of molecular rotor fluorophores Special Collection:Aggregation-Induced Processes and Functions

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Aggregate

Aggregate 2024年第1期5卷 367-376页

作者： Baoxing Shen Lihua Liu Yubo Huang Jichun Wu Huan Feng Yu Liu He Huang Xin Zhang Department of Chemistry Research Center for Industries of the FutureWestlake UniversityHangzhouChina Westlake Laboratory of Life Sciences and Biomedicine HangzhouChina School of Food Science and Pharmaceutical Engineering Nanjing Normal UniversityNanjingChina CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina

Molecular rotor-based fluorophores(RBFs)activate fluorescence upon increase of micro-viscosity,thus bearing a broad application promise in many ***,it remains a challenge to control how fluorescence of RBFs responds to viscosity ***,we demonstrate that the formation and regulation of intramolecular hydrogen bonds in the excited state of RBFs could modulate their rotational barrier,leading to a rational control of how their fluorescence can be activated by *** on this strategy,a series of RBFs were developed based on 4-hydroxybenzylidene-imidazolinone(HBI)that span a wide range of viscosity *** with the AggTag method that we previously reported,the varying viscosity sensitivity and emission spectra of these probes enabled a dualcolor imaging strategy that detects both protein oligomers and aggregates during the multistep aggregation process of proteins in live *** summary,our work indicates that installing intracellular excited state hydrogen bonds to RBFs allows for a rational control of rotational barrier,thus allow for a fine tune of their viscosity *** RBFs,we envision similar strategies can be applied to control the fluorogenic behavior of a large group of fluorophores whose emission is dependent on excited state rotational motion,including aggregation-induced emission fluorophores.

关键词： fluorescent probe intramolecular hydrogen bond protein aggregation rotor-based fluorophores viscosity sensitivity

Synthesis and Optical Property of a New Zinc Complex Based on the Derivative of 2-(2’-Hydroxyphenyl)-1H-benzimidazole and Phenanthroline

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Chinese Journal of Structural Chemistry 2021年第4期40卷 487-494,407页

作者：尹国杰张浩玉田文杰赵丹张斌陈冬梅 School of Environmental Engineering and Chemistry Luoyang Institute of Science and TechnologyLuoyang 471023China College of Chemistry Zhengzhou UniversityZhengzhou 450000China

A novel zinc complex(ZnE) has been designed and synthesized based on the derivative of 2-(2’-hydroxyphenyl)-1-H-benzimidazole(HBI) and the neutral nitrogen-containing ligand(phen). The crystal of the title complex crystallizes in the monoclinic system, space group P2_(1)/n with a = 10.2631(2), b = 34.2166(6), c = 11.4103(3) A, β = 96.771(2)°, M_(r )= 844.24, V = 3978.99(14) A^(3), Z = 4, the final R = 0.0400 and wR = 0.1001 for 8107 observed reflections(I > 2σ(I)). In the title complex, the free protonated phenoxide moiety(4-OH) is successfully retained to realize pseudo-intramolecular hydrogen bonds with the coordinated O atom from the other ligand.

关键词： synthesis proton transfer intramolecular hydrogen bond

Synthesis and Structural Characterization of N,N-disubstituted Acylguanidines

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Chinese Journal of Structural Chemistry 2018年第5期37卷 710-718页

作者：王凡凡侯宪辉朱成奔李海普杨鹰 School of Chemistry and Chemical Engineering Centre for Environment and Water Resource Central South University

A series of five N,N-disubstituted acylguanidines R1C（O）N=C[N（H）R2]NR23（R1=Mes or Ph; R2=Ar′′or Ar′; R3=Cy, Bn, iPr, or Et）（Mes=2,4,6-Me3C6H2, Ar′′=2,6-iPr2C6H3, Ar′=2,6-Me2C6H3） was synthesized from the reactions of parent acylthioureas with respective secondary amines. According to structutral characterization by single-crystal X-ray diffraction, the rough reduction of the steric hindrance of R substitutents of R1 C（O）N=C[N（H）R2]NR23（also abbreviated as R1-R2-R3 for comparison purposes） led to the slight enlongation of N（1）–C（1） bond lengthes and small decrease of N（1）–C（1）–N（3） bond angles from Mes–Ar′′–Cy（1） to Ph–Ar′′–Bn（2）, Ph–Ar′′–iPr（3） and Ph–Ar′–Cy（4）. At the same time, the N（1）–H（1）···O（1） intramolecular hydrogen bonds were observed in these cases. When R3=Et, an interesting compound Ph-Ar′-Et（5） was obtained with the formation of intermolecular hydrogen bonds instead. 1 belongs to the monoclinic system, space group P2（1/n） with a=9.6488（3）, b=28.5318（8）, c=11.9155（3） A, b=91.439（2）°, V=3279.27（16） A3, and Z=4. 2 belongs to the triclinic system, space group P1 with a=9.6759（7）, b=10.8613（8）, c=15.7642（12） A, a=70.429（3）, b=79.257（4）, g=69.052（4）°, V=1453.63（19） A3 and Z=2. 3 belongs to the monoclinic system, space group P2（1/c） with a=11.1393（4）, b=13.0643（4）, c=17.6600（6） A, b=101.866（2）o, V=2515.09（15） A3 and Z=4. 4 belongs to the monoclinic system, space group C2/c with a=17.8466（3）, b=13.6126（2）, c=21.6710（4） A, b=90.7310（10）°, V=4992.72（14） A3 and Z=8. 5 is of orthorhombic system, space group P212121 with a=10.5555（2）, b=11.8913（2）, c=14.9558（4） A, V=1877.23（5） A3 and Z=4.

关键词： acylguanidine acylthiourea intramolecular hydrogen bond

A New Condensation Reaction of β-Keto-δ-valerolactone with Substituted Aniline

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Chinese Chemical Letters 1999年第4期10卷 269-270页

作者： You Ming WANG Jia Feng LI Zheng Ming LI(State Key Laboratory of Elemento-Organic Chemistry. Nankai University. Tianjin 300071) State Key Lab. Elemento-Organ. Chem. Nankai University Tianjin 300071 China

A new condensation reaction of β-keto-δ-valerolactones was developed. The condensation products are composed of a pair of isomers because of the formation ofintramolecular hydrogen bond. Their structures were confir... 详细信息

关键词： Condensation reaction β-keto-δ-valerolactone intramolecular hydrogen bond

Synthesis and Structure of a Mono-ionizable 1,3-alternate Triaminopyridyl-thiacalix[4]arene Derivative

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Synthesis and Structure of a Mono-ionizable 1,3-alternate Tr...