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231.
Fumio Toda Koichi Tanaka Tomoyuki Tamashima Masako Kato 《Angewandte Chemie (International ed. in English)》1998,37(19):2724-2727
A conrotatory [2+2] cyclization is the second step in the solid-state thermal reaction of s-trans-tetraaryldibromohexatetraenes 1 to cyclobutenes 4 . Prior to the cyclization 1 rearranges into the cis conformer 3 . Surprisingly the thermal rearrangement and the stereoselective cyclization occur readily in spite of the required motion of the sterically bulky substituents. R=Ph, p-MeC6H4. 相似文献
232.
Minako Shibata Atsushi Kusuno Toyoji Kakuchi Takeshi Nakato Masako Yoshikawa Masayuki Tomida 《Macromolecular Symposia》1998,130(1):229-244
The polycondensation of L-aspartic acid (1) with various ω-amino acids (2) using phosphoric acid catalyst produced poly(succinimide-co-ω-amino acid)s (3), which was followed by alkali hydrolysis to poly(aspartic acid-co-ω-amino acid) (4). The Ca2+ chelating abilities of 4 depended on the content of comonomer unit in the copolymer and on the kind of amino acids. For the copolymer using 11-aminoundecanoic acid (2d) as a comonomer, the Ca2+ chelating ability was higher than that of poly(sodium acrylate). For poly(aspartic acid-co-6-aminocaproic acid) (4c), there was a tendency to increase according to the increase of 6-aminocaproic acid (2c) unit in the copolymer. The biodegradability of the copolymer in the case of 2c as a comonomer, evaluated by TOC measurement, was 63%, which was the highest degradability among the copolymers having different methylen length. The biodegradability of 4c decreased with increasing the 2c unit in 4c. 相似文献
233.
234.
Tamami Koshiyama Masako Kato 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):m446-m449
The title PtII complexes, viz. (2,2′‐bipyridine‐κ2N,N′)[(1R,2R)‐1,2‐diaminocyclohexane‐κ2N,N′]platinum(II) bis(hexafluorophosphate), [Pt(C6H14N2)(C10H8N2)](PF6)2, and [(1R,2R)‐1,2‐diaminocyclohexane‐κ2N,N′](1,10‐phenanthroline‐κ2N,N′)platinum(II) bis(hexafluorophosphate), [Pt(C6H14N2)(C12H8N2)](PF6)2, containing an aromatic α‐diimine and a non‐planar diaminocyclohexane, both form a ladder‐type structure, which is constructed via loose π–π stacking on the α‐diimine ligands and hydrogen bonding between the cyclic amines and the counter‐anions. In the former compound, there are two independent complex cations, both of which have a twofold axis through the Pt atom. 相似文献
235.
Masako Kato Mana Ikemori 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(1):m25-m26
The title compound, [PtCl2(C28H44N2)], is a new square‐planar PtII complex containing a bipyridine moiety with two long alkyl‐chain substituents. The complex forms a segregated packing structure made up of the alkyl‐chain layers and paired coordination sites. 相似文献
236.
Yin Xinmin Li Wenxin Zhang Xiang Sun Tongyu Shizuko Ambe Yoshitaka Ohkubo Masako Iwamoto Yoshio Kobayashi Fumitoshi Ambe 《中国物理C(英文版)》1995,19(11):991-997
Cross Sections and average forward recoil range FW were measured for target residues from the interaction of Cu with 40MeV/u 40Ar ions using off-line y-ray spectroscopy.The mass yield distribution was obtained with assumption of charge distribution.The linear momentum transfer was calculated from FW values.A comparison with similar results of 12C+Cu and 20Ne+Cu reactions indicates that the fractional linear momentum transfer,corresponding to central collisions,decreases with increasing projectile mass at the same energy per nucleon. However,the excitation energy of the composite system created from the collisions of Cu with 40Ar ions reached the value of 5.3MeV /u and was higher than those from the collisions with 12C and 20Ne ions. 相似文献
237.
Fumiya Kobayashi Dr. Ryo Ohtani Saki Teraoka Dr. Masaki Yoshida Prof. Dr. Masako Kato Dr. Yingjie Zhang Prof. Dr. Leonard F. Lindoy Prof. Dr. Shinya Hayami Dr. Masaaki Nakamura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(23):5875-5879
Luminescent ZnII clusters [Zn4L4(μ3-OMe)2X2] (X=SCN ( 1 ), Cl ( 2 ), Br ( 3 )) and [Zn7L6(μ3-OMe)2(μ3-OH)4]Y2 (Y=I− ( 4 ), ClO4− ( 5 )), HL=methyl-3-methoxysalicylate, exhibiting blue fluorescence at room temperature (λmax=416≈429 nm, Φem=0.09–0.36) have been synthesised and investigated in detail. In one case the external heavy-atom effect (EHE) arising the presence of iodide counter anions yielded phosphorescence with a long emission lifetime (λmax=520 nm, τ=95.3 ms) at 77 K. Single-crystal X-ray structural analysis and time-dependent density-functional theory (TD-DFT) calculations revealed that their emission origin was attributed to the fluorescence from the singlet ligand-centred (1LC) excited state, and the phosphorescence observed in 4 was caused by the EHE of counter anions having strong CH−I interactions. 相似文献
238.
Rational Molecular Design and Synthesis of Highly Thermo‐ and Photostable Near‐Infrared‐Absorbing Heptamethine Cyanine Dyes with the Use of Fluorine Atoms
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Prof. Dr. Kazumasa Funabiki Kazutaka Yagi Masato Ueta Mitsuru Nakajima Masako Horiuchi Dr. Yasuhiro Kubota Prof. Dr. Masaki Mastui 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12282-12285
Highly thermo‐ and photostable, near‐infrared‐absorbing heptamethine cyanine dyes were achieved with the use of fluorine‐containing components. In particular, one prepared heptamethine cyanine dye, bearing a tetrakis(pentafluorophenyl)borate as a counter anion and an N‐ethyl‐2,2,2‐trifluoroacetamido group at the meso position, showed not only a high decomposition temperature (Tdt), but also very high photostability toward white LED irradiation. 相似文献
239.
Consecutive inter- and intramolecular [2+2+2] cycloadditions of various thiophenylene-tethered triynes were comprehensively studied by using chiral Rh catalysts. When we started from 2,3- and 3,4-thiophenylene-tethered substrates, dimerization proceeded and chiral tetraheteroarylenes were obtained. In contrast, reactions of 2,5-thiophenylene-tethered substrates gave hexaheteroarylenes as trimers. When bis- and tris(2,5-thiophenylene)-tethered triynes were used, mixtures of dimers and trimers were obtained, which included macrocyclic systems that contained up to 12 aromatic rings, and their photophysical properties were measured. 相似文献
240.
Fumika Yakushiji Masako Haramo Yukari MiyaderaChihiro Uchiyama Kentaro TakayamaYoshio Hayashi 《Tetrahedron letters》2014
4-Hydroxycoumarin (1) is a useful synthon in synthetic organic chemistry and a basic skeleton of several bioactive compounds. The direct functionalization of 1 with novel catalytic system would provide an efficient meaning for construction of a chemical library. Here, we developed a new catalytic system using palladium(II) acetate for the C3 regioselective mono-arylation of 1. The 3-mono-arylated and the 3,4-disubstituted coumarins were synthesized to enable derivatization. This palladium-catalyzed direct arylation of 1 is effective for rapid diversification and chemical library construction. 相似文献