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111.
Takushi Kurihara Tsutomu Tani Sigeru Maeyama Yasuhiko Sakamoto 《Journal of heterocyclic chemistry》1980,17(5):945-951
The reaction of ethyl 3-ethoymethylene-2,4-dioxovalerate (EMDV) ( 1 ) with 2-aminobenzamide ( 2 ), 2-aminobenzthioamide ( 3 ), 2-aminobenzmethylamide ( 4 ) and 3-amino-2-methyl- or phenylpyrazole-4-carbox-amides ( 6 and 7 ) produced ethyl 3-aminomethylene-2,4-dioxovalerates ( 10, 15, 16, 18 and 19 ), which led to pyrrolo[1,2-a]quinazoline-1,5-diones ( 11, 22 and 23 ) and pyrrolo[1,2-a]pyrazolo[4,3-e]pyrimidine-1,5-diones ( 24 and 25 ) under the acidic condition, respectively. Analogously, 2-aminothiophenol reacted with 1 to give 21 , which was subsequently derived to pyrrolo[1,2-a]benzothiazolin-l-one ( 26 ) under the neutral condition. Furthermore, we prepared the heterocyclic steroidal molecules ( 41, 43, 45, 47, 49 and 51 ) by condensation of 11 and 26 with hydrazine, methylhydrazine and phenylhydrazine. 相似文献
112.
Masanori Taguchi Ikuyoshi Tomita Yasuhiko Yoshida Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2001,39(4):495-499
An end‐π‐allylnickel macroinitiator ( 3 ) was prepared by the reaction of poly(ethylene glycol) allenyl methyl ether with an excess amount (5 equiv) of [(π‐allyl)NiOCOCF3]2 ( 1 ) in the presence of PPh3 ([PPh3]/[ 1 ] = 1). The resulting macroinitiator was used as an initiator for the polymerization of 1‐phenylethyl isonitrile ( 4a ) to give a block copolymer [poly(ethylene glycol)‐block‐poly( 4a )]. The molecular weight and composition of the block copolymers were controlled by the molecular weight of 3 and the ratio of 4a to 3 . © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 495–499, 2001 相似文献
113.
Rhodium complexes such as [RhCl(cod)]2, [Rh(cod)2]BF4, and [Rh(cod)(CH3CN)2]BF4 function as catalysts for carbonyl allylations by allylic alcohols with 1 equimolar amount of tin(II) chloride to each allylic alcohol and aldehyde in THF at 50 °C to produce the corresponding homoallylic alcohols. 相似文献
114.
Yasuhiko Suzuki Hidetsugu Tanaka Toshiyuki Oshiki Kazuhiko Takai Terunori Fujita 《化学:亚洲杂志》2006,1(6):878-887
New Ti and Zr complexes that bear imine–phenoxy chelate ligands, [{2,4‐di‐tBu‐6‐(RCH=N)‐C6H4O}2MCl2] ( 1 : M=Ti, R=Ph; 2 : M=Ti, R=C6F5; 3 : M=Zr, R=Ph; 4 : M=Zr, R=C6F5), were synthesized and investigated as precatalysts for ethylene polymerization. 1H NMR spectroscopy suggests that these complexes exist as mixtures of structural isomers. X‐ray crystallographic analysis of the adduct 1 ?HCl reveals that it exists as a zwitterionic complex in which H and Cl are situated in close proximity to one of the imine nitrogen atoms and the central metal, respectively. The X‐ray molecular structure also indicates that one imine phenoxy group with the syn C?N configuration functions as a bidentate ligand, whereas the other, of the anti C?N form, acts as a monodentate phenoxy ligand. Although Zr complexes 3 and 4 with methylaluminoxane (MAO) or [Ph3C]+[B(C6F5)4]?/AliBu3 displayed moderate activity, the Ti congeners 1 and 2 , in association with an appropriate activator, catalyzed ethylene polymerization with high efficiency. Upon activation with MAO at 25 °C, 2 displayed a very high activity of 19900 (kg PE) (mol Ti)?1 h?1, which is comparable to that for [Cp2TiCl2] and [Cp2ZrCl2], although increasing the polymerization temperature did result in a marked decrease in activity. Complex 2 contains a C6F5 group on the imine nitrogen atom and mediated nonliving‐type polymerization, unlike the corresponding salicylaldimine‐type complex. Conversely, with [Ph3C]+[B(C6F5)4]?/AliBu3 activation, 1 exhibited enhanced activity as the temperature was increased (25–75 °C) and maintained very high activity for 60 min at 75 °C (18740 (kg PE) (mol Ti)?1 h?1). 1H NMR spectroscopic studies of the reaction suggest that this thermally robust catalyst system generates an amine–phenoxy complex as the catalytically active species. The combinations 1 /[Ph3C]+[B(C6F5)4]?/AliBu3 and 2 /MAO also worked as high‐activity catalysts for the copolymerization of ethylene and propylene. 相似文献
115.
Yasuhiko Kurusu 《先进技术聚合物》1996,7(2):67-72
In order to produce a polymer with an epoxy group, the epoxidation of the polyolefins poly(ethylene-co-1,9-decadiene) (PED) and polybutadiene (PB) was investigated. For these reactions, in situ generated peroxy acid was most effective and convenient. Among them an H2O2–formic acid system gave the best result. The reactivity of PB showed the dependency on the microstructure. The reactivity of the double bond is trans>cis> vinyl(pendant) and the selectivity for the epoxidation is cis∼vinyl(pendant)≫trans. 相似文献
116.
Satoh Shin -Ichi Nakajima Takahiro Shirota Yasuhiko 《Research on Chemical Intermediates》1995,21(8-9):939-949
Research on Chemical Intermediates - The photochemical reaction of a 2-vinylnaphthalene — dichloromaleic anhydride system has been studied in order to elucidate the correlation between the... 相似文献
117.
Tsuyoshi Honma Rie Ihara Yasuhiko Benino Ryuji Sato Takumi Fujiwara Takayuki Komatsu 《Journal of Non》2008,354(2-9):468-471
We examined the laser-induced crystallization to form the fresnoite type Ba2TiGe2O8 crystal line patterns in transition metal ion doped BaO–TiO2–GeO2 glass. Ba2TiGe2O8 crystal line was written in 0.6FeO–33.3BaO–16.7TiO2–50GeO2 glass by continuous wave yttrium–aluminum–garnet (YAG) laser irradiation. We obtained polarization dependence of Raman spectra in crystal line pattern. Second harmonic generation (SHG) indicated unique fringe patterns from Ba2TiGe2O8 crystal lines. 相似文献
118.
Recent advances in quantum dots (QDs) for classical and non-classical light sources are presented. We have established metal organic chemical vapor deposition (MOCVD) technology for InAs-based QD lasers at 1.3 μm and achieved ultralow threshold in QD lasers with photonic crystal (PhC) nanocavity. In addition, single photon emitters at 1.55/μm, GaN-based single photon sources operating at 200 K, and high-Q PhC nanocavity have been demonstrated. 相似文献
119.
Kitagawa Y Sentoku Y Akamatsu S Sakamoto W Kodama R Tanaka KA Azumi K Norimatsu T Matsuoka T Fujita H Yoshida H 《Physical review letters》2004,92(20):205002
An ultraintense laser injected a 10 J of power at 1.053 microm in 0.5 ps into a glass capillary of 1 cm long and 60 microm in diameter and accelerated plasma electrons to 100 MeV. One- and two-dimensional particle codes describe wakefields with 10 GV/m gradient excited behind the laser pulse, which are guided by a plasma density channel far beyond the Rayleigh range. The blueshift of the laser spectrum supports that a plasma of 10(16) cm(-3) is inside the capillary. A bump at the high energy tail suggests the electron trapping in the wakefield. 相似文献
120.
A series of [1, 2, 4]triazolo[1, 5-b]pyridazines (5) and imidazo[1, 2-b]pyridazines (6) having cyclic amines was synthesized and evaluated for antihistaminic activity and inhibitory effect on eosinophil infiltration. When a piperidine or a piperazine containing a benzhydryl group and a suitable spacer was incorporated at the 6-position, the fused pyridazines were found to exhibit both antihistaminic activity and an inhibitory effect on eosinophil chemotaxis. Above all, 6a showed potent antihistaminic activity, but little blockade of central H(1) receptors in contrast with its complete blockade of peripheral H(1) receptors as determined by an ex vivo binding assay. Furthermore, 6a inhibited eosinophil infiltration of the skin caused by a topical antigen challenge in sensitized guinea pigs, while an antihistamine terfenadine was not effective. After the pharmacokinetic study, 6a was found to be rapidly hydrolyzed to 6o, which was also orally active. Compound 6o, 2-[6-[[3-[4-(diphenylmethoxy)piperidino]propyl]amino]imidazo[1, 2-b]pyridazin-2-yl]-2-methylpropionic acid dihydrate (TAK-427), having both antihistaminic and antiinflammatory activity, is currently undergoing clinical trials as a therapeutic agent for atopic dermatitis and allergic rhinitis. 相似文献