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Molecular rotor based on an oxidized resorcinarene

Organic Chemistry Frontiers 2022年第1期9卷 39-50页

作者： Daniel T.Payne Jan Labuta Zdeněk Futera václav b.ezina Lenka Hanyková Mandeep K.Chahal Jonathan P.Hill International Center for Materials Nanoarchitectonics National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan bInternational Center for Young Scientists National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan Institute of Physics Faculty of ScienceUniversity of South BohemiaBranišovská1760ČeskéBudějovice 37005Czech Republic Faculty of Mathematics and Physics Charles UniversityV Holešovičkách 218000 Prague 8Czech Republic

Molecular rotors are an important class of dynamic molecules which have been studied not only for their possible uses as components of molecular machines but also because of potential applications as probes of local viscosity in biological media,especially self-assembled *** the former,factors affecting rotational motility are critical while for the latter the rotor activity must be complexed with an output signal(often fluorescence)for reporting of local *** single stator-double rotor activity of an oxidized resorcinarene(fuchsonarene)macrocycle containing unsaturated hemiquinonoid groups at its meso positions was *** contain two hemiquinonoid substituents at diagonally-opposed meso-positions with two electron rich phenol groups at the remaining meso-positions between the hemiquinonoid *** meso-substituents are in proximity at one side of the resorcinarene macrocycle(so-called rccc-type isomer)with rotational activity of the phenol *** rates of the phenol moieties can be controlled by varying temperature,solvent polarity and acidity of the medium of study with rotation being thermally activated in neutral and acidic media and tunable in the range from 2 s^(−1) to 20000 s^(−1).Experimental and computational data indicate that rotation of the mobile phenol meso-substituents is remotely affected by interactions with acidic solvents at the carbonyl CvO groups of macrocyclic acetyloxy groups,which occurs with the emergence of a lower energy electronic absorption band whose intensity is correlated with both the acidity of the medium and the rotation rate of the phenol ***-dependent DFT calculations suggest that the low energy band is due to a molecular conformational adjustment affecting electronic conjugation caused by strong interaction of macrocyclic acetyloxy carbonyl groups with the acid *** work presents a molecular mechanical model for estimating solution acidity a

关键词： substituent rotation oxidized

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Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 28-40页

作者： Daniel T.Payne Mandeep KChahal vaclav b.ezina Whitney A.Webre Katsuhiko Ariga Francis D’Souza Jan Labuta Jonathan P.Hill WPI Center for Materials Nanoarchitectonics National Institute for Materials ScienceIbaraki 305-0044Japan Department of Macromolecular Physics Faculty of Mathematics and PhysicsCharles University18000 PragueCzech Republic Department of Chemistry University of North TexasDentonTX 76203USA Department of Advanced Materials Science Graduate School of Frontier SciencesThe University of TokyoChiba 277-8561Japan

Chiral 1,1’-binaphthyl-linked diporphyrin‘tweezers’(R)-1/(S)-1 and the corresponding zinc(II)complexes(R)-2/(S)-2 were prepared as chiral host molecules,and their utility for chiral analyses(especially enantiomeric excess(ee)determinations)were ***(1-n-dodecyl)porphyrins were used for the first time as the interacting *** capabilities of the diporphyrin tweezers were investigated by titrations with(R,R)-and(S,S)-cyclohexane-1,2-diamine(CHDA).The host molecules could be used as multichannel probes of ee by using Uvvis,circular dichroism(CD),fluorescence emission and 1H nuclear magnetic resonance(1 H-NMR)*** configurations could also be differentiated using CD or 1HNMR *** three optical techniques give good resolution of ee with reasonable sensitivity considering the low concentrations used(ca.10^-6 mol·L^-1).The ee determination of CHDA enantiomers using NMR spectroscopy is also possible because of the reasonably well separated resonances in the case of(R,R)-and(S,S)-***-metallated(R)-1/(S)-1 hosts could not be used to detect chiral information in a strongly acidic chiral *** work demonstrates the utility of 1,1’-binapthyllinked chiral hosts for chiral analysis of ditopically interacting enantiomers.

关键词： porphyrin dimer chirality enantiomeric excess CD fluorescence

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RESULTS FROM IRRADIATION EMbRITTLEMENT MONITORING PROGRAMMES OF RPv’S OPERATED IN THE SLOvAK REPUbLIC NPP’S

RESULTS FROM IRRADIATION EMBRITTLEMENT MONITORING PROGRAMMES...

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第十八届国际反应堆结构力学大会

作者： Peter be■o L’udovít Kupa Martin b.ezina vUJE Inc TrnavaSlovak Republic vUJE Inc TrnavaSlovak Republic vUJE Inc TrnavaSlovak Republic

＜正＞ 1 INTRODUCTION The actual status and main results from the irradiation embrittlement monitoring programmes application on the RPv’s WWER-440 in the Slovak Republic are presented in the paper. 2 SURvEILLANCE PROGRAMMES IN THE SLOvAK NPP’S Five types of surveillance programmes were （are） realized in Slovak NPP’s: in Jaslovske bohunice v-2 NPP （units 3 and 4）, was finished the original "Standard Surveillance Specimen Program" （SSSP）,

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氧气转炉出钢温度的最佳化

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武钢技术 1991年第6期29卷 25-28,33页

作者： J.b.ezina 刘树振

一、前言氧气转炉出钢温度是一个重要的综合性指标,它显著影响炼钢生产的能源消耗。影响出钢温度的因素有:①未脱氧的钢液;②钢包的温度;③出钢的方式和时间以及脱氧和合金化的物理化学参数。出钢时钢包内钢液的热容量、炉外精炼和浇铸... 详细信息

一、前言氧气转炉出钢温度是一个重要的综合性指标,它显著影响炼钢生产的能源消耗。影响出钢温度的因素有:①未脱氧的钢液;②钢包的温度;③出钢的方式和时间以及脱氧和合金化的物理化学参数。出钢时钢包内钢液的热容量、炉外精炼和浇铸过程都对钢液温度有影响。

关键词：氧气转炉出钢温度最佳化

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