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131.
132.
A. K. M. Fakhrul Azam Masami Kamigaito Yoshio Okamoto 《Journal of polymer science. Part A, Polymer chemistry》2007,45(7):1304-1315
N‐(1‐Phenyldibenzosuberyl)methacrylamide (PDBSMAM) and its derivative N‐[(4‐butylphenyl)dibenzosuberyl]methacrylamide (BuPDBSMAM) were synthesized and polymerized in the presence of (+)‐ and (?)‐menthols at different temperatures. The tacticity of the polymers was estimated to be nearly 100% isotactic from the 1H NMR spectra of polymethacrylamides derived in D2SO4. Poly(PDBSMAM) was not soluble in the common organic solvents, and its circular dichroism spectrum in the solid state was similar to that of the optically active poly(1‐phenyldibenzosuberyl methacrylate) (poly(PDBSMA)) with a prevailing one‐handed helicity, indicating that the poly(PDBSMAM) also has a similar helicity. Poly(BuPDBSMAM) was optically active and soluble in THF and chloroform. Its optical activity was much higher than that of the poly[N‐(triphenylmethayl)methacrylamide], suggesting that one‐handed helicity may be more efficiently induced on the poly(BuPDBSMAM). The copolymerization of BuPDBSMAM with a small amount of optically active N‐[(R)‐(+)‐1‐(1‐naphthyl)ethyl]methacrylamide, particularly in the presence of (?)‐menthol, produced a polymer with a high optical activity. The prevailing helicity may also be efficiently induced. The chiroptical properties of the obtained polymers were studied in detail. The chiral recognition by the polymers was also evaluated. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1304–1315, 2007 相似文献
133.
Back Cover: Simultaneous Assessment of Kinetic,Site‐Specific,and Structural Aspects of Enzymatic Protein Phosphorylation (Angew. Chem. Int. Ed. 36/2014) 下载免费PDF全文
134.
Masami Yonemura Yuuki Nakamura Naoki Usuki Hisashi kawa 《Journal of Chemical Sciences》2000,112(3):291-310
This paper discusses coordination-position isomeric MIICuII and CuIIMII complexes, using unsymmetric dinucleating macrocycles (Lm;n)2− ((L2;2)2−, (L2;3)2− and (L2;4)2−) that comprise two 2-(N-methyl)-aminomethyl-6-iminomethyl-4-bromo-phenonate entities, combined through the ethylene chain
(m = 2) between the two amine nitrogens and through the ethylene, trimethylene or tetramethylene chain(n = 2, 3 or 4) between the two imine nitrogens. The macrocycles have dissimilar N(amine)2O2 and N(imine)2O2 metal-binding sites sharing the phenolic oxygens. The reaction of the mononuclear CuII precursors, [Cu(L2;2)], [Cu(L2;2)] and [Cu(L2;2)], with a MII perchlorate and a MII acetate salt formed (acetato)MIICuII complexes: [CoCu(L2;2)(AcO)]ClO4·0.5H2O] (1), [NiCu(L2;2) (AcO)]ClO4 (2), [ZnCu(L2;2) (AcO)]ClO4 (3), [CoCu(L2;3)(AcO)]ClO4·0.5H2O (4), [NiCu(L2;3)(AcO)]ClO4 (5), [ZnCu(L2;3)(AcO)]ClO4·0.5H2O (6), [CoCu(L2;4)(AcO)(DMF)]ClO4 (7), [NiCu(L2;4) (AcO)]ClO4·2DMF (8) and [ZnCu(L2;4)(AcO)]ClO4 (9) (the formulation [MaMb (Lm;n)]2+ means that Ma resides in the aminic site and Mb in the iminic site). The site selectivity of the metal ions is demonstrated by X-ray crystallographic studies for 2·MeOH,3,5,7, and9. An (acetato)CuIIZnII complex, [CuZn(L2;3)(AcO)]ClO4 (10), was obtained by the reaction of [PbCu(L2;3)]-(ClO4)2 with ZnSO4·4H2O, in the presence of sodium acetate. Other complexes of the CuIIMII type were thermodynamically unstable to cause a scrambling of metal ions. The Cu migration from the iminic site to the aminic
site in the synthesis of10 is explained by the ‘kinetic macrocyclic effect’. The coordination-position isomers,6 and10, are differentiated by physicochemical properties. 相似文献
135.
Inside Cover: Supramolecular Porphyrin‐Based Metal–Organic Frameworks with Fullerenes: Crystal Structures and Preferential Intercalation of C70 (Chem. Asian J. 5/2016) 下载免费PDF全文
136.
Takehiko Nishio Nobuharu Sakurai Kaoru Iba Yo‐ichi Hamano Masami Sakamoto 《Helvetica chimica acta》2005,88(10):2603-2609
The photochemical reactions of 2‐acylphenyl methacrylates (= 2‐acylphenyl 2‐methylprop‐2‐enoates) 1 were investigated. Irradiation of 2‐acylphenyl methacrylates 1a – d in MeCN gave the tricyclic lactones 2a – d in good yields, together with a small amount of O CO bond cleavage product, the 2‐acylphenols 3a – d (Scheme 2, Table). The formation of the tricyclic lactones 2 probably follows a mechanism involving a 1,7‐diradical through ζ‐H abstraction (1,8‐H transfer) by the excited carbonyl O‐atom (Scheme 3). Irradiation of 2‐acylphenyl tiglate (= 2‐acylphenyl (2E)‐2‐methylbut‐2‐enoate) 1e and 2‐acylphenyl methacrylates 1g – i , substituted by a MeO group (δ‐H) at the 3,5‐positions of the phenyl group, also gave the tricyclic lactones 2e and 2g – i , but in low yields. On the other hand, no H‐abstraction products were observed on irridation of 2‐(ethoxycarbonyl)phenyl methacrylate 1f , of 2‐acylphenyl methacrylate 1j which is substituted by a Me group (γ‐H) at the 3,5‐positions of the phenyl group, and of 1k with an OH group at the 3‐position of the phenyl group. 相似文献
137.
138.
Peter G. Kirira Masami Kuriyama Dr. Osamu Onomura Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(13):3970-3982
Electrochemical oxidation of α‐allylated and α‐benzylated N‐acylated cyclic amines by using a graphite anode easily affords the corresponding α‐methoxylated products with up to 76 % yield. Ease of oxidation was affected by the type of electrode, the size of cyclic amine, and the nature of the protecting group. This method was successfully applied to the synthesis of optically active N‐acylated α‐alkyl‐α‐amino acid esters with up to 99 % ee. 相似文献
139.
Effects of initial water content on steam reforming of aliphatic hydrocarbons with nonthermal plasma
The effects of initial water content on steam reforming of aliphatic hydrocarbons such as methane, propane, and neopentane with nonthermal plasma were analyzed in terms of substrate conversion, carbon recovery, and product selectivity. It was found that water addition increased CO2 yield despite a decrease in substrate conversion. The number of carbon atoms in the substrate hydrocarbon affected the additive effect due to the insufficient supply of oxygen atoms from water. Plausible reaction pathways for the conversion of substrate to COx are proposed to explain the relative concentrations of COx species; these pathways involved different precursors for CO and CO2. 相似文献
140.
Masami Nishikawa Tomohiko Nakajima Toshiya Kumagai Takeshi Okutani Tetsuo Tsuchiya 《Applied Physics A: Materials Science & Processing》2010,100(1):297-303
Epitaxial VO2 films were prepared on the TiO2 (001) substrates by the excimer-laser-assisted metal–organic deposition (ELAMOD). The quality of the epitaxial films obtained
by irradiation with a KrF laser was found to be affected by the film structure obtained after preheating at 500 or 300°C.
When the films containing crystal domains, which were obtained by preheating at 500°C, were irradiated with the laser at room
temperature under a base pressure of 250 Pa, epitaxial and polycrystalline VO2 phases were simultaneously formed. In contrast, when the amorphous films containing organic components, which were obtained
by preheating at 300°C, were irradiated with the laser at room temperature in air, a single phase of epitaxial VO2 was formed. By using thermal simulations, we determined that the formation of the epitaxial phase was affected both by the
temperature distribution within the film during the laser irradiation and by the laser intensity at the interface between
the substrate and the film. The latter factor is considered to play a role in the nucleation of crystallization, causing the
epitaxial phase to form preferentially compared to the polycrystalline phase in the amorphous matrix of the films. These results
indicate that the ELAMOD process is effective for the fabrication of epitaxial VO2 films at low temperature. 相似文献