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101.
Comprehensive Understanding of Structure‐Controlling Factors of a Zinc Tetraphenylporphyrin Thin Film Using pMAIRS and GIXD Techniques
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Miyako Hada Nobutaka Shioya Prof. Takafumi Shimoaka Prof. Kazuo Eda Prof. Masahiko Hada Prof. Takeshi Hasegawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16539-16546
The performance of an organic electronic device is significantly influenced by the anisotropic molecular structure in the film, which has long been difficult to predict especially for a solution process. In the present study, a zinc tetraphenylporphyrin (ZnTPP) thin film prepared by a solution process was chosen to comprehensively explore the molecular‐arrangement mechanism as a function of representative film‐preparation parameters: solvent, film‐preparation technique, and thermal annealing. The anisotropic structure was first analyzed by using a combination of infrared p‐polarized multiple‐angle incidence resolution spectrometry (pMAIRS) and grazing incidence X‐ray diffraction (GIXD), which readily revealed the molecular orientation and crystal structure, respectively. As a result, the real dominant factor was found to be the evaporation time of the solvent that determines the initial two different molecular arrangements, types‐I and ‐II, while the thermal annealing was found to play an additional role of improving the molecular order. The correlation between the molecular orientation and the crystal structure was also revealed through the individual orientation analysis of the porphyrin and phenyl rings. 相似文献
102.
103.
Wakahara T D'Angelo P Miyazawa K Nemoto Y Ito O Tanigaki N Bradley DD Anthopoulos TD 《Journal of the American Chemical Society》2012,134(17):7204-7206
A novel supramolecular nanoarchitecture, comprising C(60)/Co porphyrin nanosheets, was prepared by a simple liquid-liquid interfacial precipitation method and fully characterized by means of optical microscopy, AFM, STEM, TEM, and XRD. It is established that the highly crystalline C(60)/Co porphyrin nanosheets have a simple (1:1) stoichiometry, and when incorporated in bottom-gate, bottom-contact field-effect transistors (FETs), they show ambipolar charge transport characteristics. 相似文献
104.
Naoe S Suzuki Y Hirano K Inaba Y Oishi S Fujii N Ohno H 《The Journal of organic chemistry》2012,77(11):4907-4916
The gold-catalyzed cascade intermolecular addition-intramolecular carbocyclization reaction of dialkynylbenzenes was developed. In this reaction, regioselective addition of an external nucleophile toward the terminal alkyne and subsequent 6-endo-dig cyclization proceeded to give the 1,3-disubstituted naphthalenes in good yields. The direct synthesis of disubstituted chrysenes via a gold-catalyzed addition and double cyclization cascade using a triyne-type substrate was also achieved. 相似文献
105.
Suzuki Y Oishi S Takei Y Yasue M Misu R Naoe S Hou Z Kure T Nakanishi I Ohno H Hirasawa A Tsujimoto G Fujii N 《Organic & biomolecular chemistry》2012,10(25):4907-4915
Two classes of fused nitrogen heterocycles were designed as CK2 inhibitor candidates on the basis of previous structure-activity relationship (SAR) studies. Various dipyrrolo[3,2-b:2',3'-e]pyridine and benzo[g]indazole derivatives were prepared using transition-metal-catalysed cascade and/or multicomponent reactions. Biological evaluation of these candidates revealed that benzo[g]indazole is a promising scaffold for potent CK2 inhibitors. The inhibitory activities on cell proliferation of these potent CK2 inhibitors are also presented. 相似文献
106.
Shinya Oishi Kazuhide Miyamoto Mikio Yamamoto Hirokazu Tamamura Yoshihiro Kuroda Nobutaka Fujii 《Tetrahedron》2006,62(7):1416-1424
The first application of a combination of novel ψ[(E)-CXCX]-type alkene dipeptide isosteres to conformation studies of cyclic bioactive peptides was carried out (X=H or Me). For exploration of bioactive conformations of Kessler's cyclic RGD peptides, cyclo(-Arg-Gly-Asp-d-Phe-Val-) 1 and cyclo(-Arg-Gly-Asp-d-Phe-N-MeVal-) 2, d-Phe-ψ[(E)-CXCX]-l-Val-type dipeptide isosteres were utilized having di-, tri- and tetrasubstituted alkenes containing the γ-methylated isosteres that have been reported to be potential type II′ β-turn promoters. All of the (E)-alkene pseudopeptides 3-6 exhibited higher antagonistic potency against αvβ3 integrin than 1, although potencies were slightly lower than 2. Detailed structural analysis using 1H NMR spectroscopy revealed that representative type II′ β/γ backbone arrangements proposed for 1, were not observed in peptides 3-6. Rather on the basis of 1H NMR data, the conformations of peptides 3-6 were estimated to be more analogous to those of the N-methylated peptide 2. 相似文献
107.
Niida A Tanigaki H Inokuchi E Sasaki Y Oishi S Ohno H Tamamura H Wang Z Peiper SC Kitaura K Otaka A Fujii N 《The Journal of organic chemistry》2006,71(10):3942-3951
Organocopper-mediated anti-SN2' reactions of gamma-phosphoryloxy-alpha,beta-unsaturated-delta-lactams were used to prepare highly functionalized diketopiperazine mimetics. The substrate phosphates 24, 32, and 47 were prepared from alpha-amino acid-derived allylic alcohols 10 by a sequence of reactions that included ring-closing metathesis. In the reactions of phosphates with organocopper reagents, the addition of LiCl dramatically improved anti-SN2' selectivity, indicating that an organocopper cluster containing lithium chloride plays an important role in the determination of regioselectivity. This reaction system was applied to the preparation of novel low molecular weight CXCR4-chemokine receptor antagonists. 相似文献
108.
We measured the voltage between two Ag/AgCl electrodes, one inserted into the seedling of the salt-tolerant plant Bruguiera gymnorrhiza and the other into the vermiculite in which the seedling was potted. Four seedlings were placed in different environments, in saltwater or pure water, with light or alternating light/dark conditions. We have found that (1) the voltage profiles showed periodical oscillatory behavior; (2) seedlings in saltwater showed higher voltage compared to the ones in pure water; (3) in the light environment, the voltage was higher compared to the one in the dark environment; (4) in the dark environment, a voltage wave was hardly observable; and (5) electrodes inserted into the propagule cortex, stem cortex, and petiole showed different voltage wave amplitudes. The voltage profiles will provide an effective way to evaluate the movement of salt water inside the salt-tolerant plant. 相似文献
109.
Hiroyuki Mochizuki Toshiko Mizokuro Nobutaka Tanigaki Takashi Hiraga Ichiro Ueno 《先进技术聚合物》2005,16(1):67-69
The surface of bisphenol‐A‐polycarbonate (BAPC) showing a stable amorphous state can be crystallized by the “vapor transportation method”. Crystallized BAPC was employed as the novel simple storage medium and bit patterns were recorded on its surface by laser irradiation. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
110.
Nobutaka Tanigaki Claire Heck Toshiko Mizokuro Yousei Shibata Tetsuhiko Miyadera Tomoyuki Koganezawa 《Molecular Crystals and Liquid Crystals》2015,621(1):118-123
Low-band-gap polymers are promising materials for organic photovoltaic application. We prepared an oriented thin film of a low-band-gap polymer, PTB7, by friction transfer method. The oriented film showed a strong dichroic absorption in the whole visible range. The orientation of molecular chain was characterized by two-dimensional grazing incident X-ray diffraction (2D-GIXD) with synchrotron radiation. 2D-GIXD results showed PTB7 molecular plane parallel to the substrate plane, i.e., “face on orientation.” 相似文献