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911.
Summary The title complexes [ML2]n+=CoIII, CuII, NiII; L=1-thia-4,7-diazacyclononane-S-oxide) have been prepared and characterized spectroscopically. The sulphoxide group is coordinated through the oxygen atom and the complexes have atrans-O,O geometry. The nickel(II) complex of bis(2-amino-ethyl)sulphoxide has also been studied. 相似文献
912.
Jun-ichi Matsuo 《Tetrahedron letters》2006,47(3):267-271
Catalytic and stereoselective glycosylation efficiently proceeded by activating a glycosyl N-trichloroacetylcarbamate with a catalytic amount of Lewis acids in the presence of a glycosyl acceptor and molecular sieves 5 Å. Catalytic and one-pot dehydrative glycosylation of a 1-hydroxy carbohydrate was also performed stereoselectively by the reaction with trichloroacetyl isocyanate followed by activation with a catalytic amount of activators. 相似文献
913.
Keizo Matsuo Seishi Machida 《Journal of polymer science. Part A, Polymer chemistry》1972,10(1):187-194
Several pairs of cis- and trans-3-substituted acrylic acids (3SAA) were copolymerized with acrylamide in order to determine the major factors affecting the relative reactivities of geometrical isomers of 1,2-disubstituted ethylenes (1,2-DE). The results were that the relative reactivity of cis isomer is larger than that of trans isomer when one substituent is electron-withdrawing and the other is electron-donating. The trans isomer is more reactive than the cis isomer when both substituents are electron-withdrawing. A new method of reactivity comparison of cis- and trans-1,2-DE is proposed in regard to the inductive substituent constant. 相似文献
914.
Takasuke Matsuo Osamu Yamamuro Masaharu Oguni Hiroshi Suga 《Journal of Thermal Analysis and Calorimetry》1996,46(3-4):1167-1176
Calorimetric properties of potassium dihydrogen phosphate are examined by analysis of the heat capacity data taken from the literature and from a recent measurement. The analysis is based on an extensive use of harmonic heat capacity functions to separate the effect of the phase transition from the vibrational contribution. The transition enthalpy and entropy derived are 421 J mol–1 and 3.79 J K–1 mol–1, respectively. Characteristic temperatures of the lattice vibrations including the Debye temperature (254±18) K were determined. The transition entropy, exceeding the value compatible with the ice-rules, is consistent with the temperature dependence of the heat capacity. The implication of the result is discussed by comparison with the hydrogen bond networks in copper formate tetrahydrate and thallium dihydrogen phosphate.Dedicated to Professor Bernhard Wunderlich on the occasion of his 65th birthdayContribution No. 113 from Microcalorimetry Research Center. 相似文献
915.
Summary When platinum(II) chloride dissolved in acetic acid containing concentrated hydrochloric acid was refluxed withN-phenylpyrazole(liphpz) andN-(p-tolyl)pyrazole (Htlpz), complexes of composition [Pt(N-C)Cl]2 (N-C = phpz, tlpz) were obtained, in which phpz and tlpz are coordinated through nitrogen and carbon forming a five membered metallocycle. Similar palladium(II) complexes [Pd(N-C)Cl]2 were easily prepared by the reaction of palladium(II) chloride with Hphpz and Htlpz in methanol in the presence of lithium chloride. These [M(N-C)CI]2 complexes reacted with tri-n-butylphosphine (PBu3) and pyridine (py) to give the adducts [M(N-C)ClL](L = PBu3, py). Ethylenediamine(en) and acetylacetone(Hacac) gave IPd(phpz)(en)]Cl and [Pd(phpz)(acac)] respectively. These new complexes are characterized by means of1H-n.m.r. and i.r. spectra, and probable structures are proposed.Reprints of this article are not available. 相似文献
916.
G. Zheng K. Suzuki Y. Takahashi H. Shimizu A. Kuno M. Matsuo 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(1):43-50
Summary A method has been developed for analyzing pyrite quantitatively in the sediments of Erhai Lake in southwest China using 57Fe M?ssbauer spectroscopy combined with a series of acidic pre-treatments. Following a washing with an alkaline solution (0.1N
NaOH), the sediment samples were successively treated using HCl, HF, and then HCl (65 °C). The residues thus prepared were
analyzed for pyrite using 57Fe M?ssbauer spectrometry. The presence of pyrite was also confirmed in the acidic residues of the sediments using sulfur
K-edge X-ray absorption near edge structure. This method can be used to measure pyrite in aquatic sediments, especially when
the concentration of pyrite is very low and the particles of pyrite are small or the crystallinity is low, and even in amorphous
status. In addition, vertical variations of pyrite contents are positively correlated with organic matter and negatively correlated
with hematite, superfine paramagnetic ferric iron and sedimentation rate in the cored sediment from the Erhai Lake. All these
geochemical indicators may also reflect environmental changes in sedimentation conditions and diagenesis. 相似文献
917.
918.
Hayashida O Mizuki K Akagi K Matsuo A Kanamori T Nakai T Sando S Aoyama Y 《Journal of the American Chemical Society》2003,125(2):594-601
Macrocyclic glycocluster compounds 2n (n = 2-7) with four alkyl (undecyl) chains and eight oligosaccharide moieties on the opposite sides of the calix[4]resorcarene macrocycle are prepared from the reactions of the corresponding octaamine derivative with maltooligosaccharide lactones. Combined evidence from dynamic light scattering (DLS), gel permeation chromatography (GPC), and transmission electron microscopy (TEM) indicates that they form small micelle-like nanoparticles (d congruent with 3 nm) in water. In the presence of Na2HPO4/NaH2PO4, nanoparticles are agglutinated with phosphate ions as a glue to grow in size up to 60-100 nm, as revealed by DLS as well as microscopy (TEM and AFM). The phosphate-induced agglutination processes can be followed by surface plasmon resonance (SPR). Amphiphile 2n is readily immobilized on the hydrophobized sensor chip of SPR to give a closely packed monolayer with oligosaccharide moieties exposed to bulk water. While there is no further adsorption of 2n on the resulting monolayer, this does occur when the latter is pretreated with the phosphate salts, ultimately giving rise to a multilayer upon repeated treatment of the chip with 2n and Na2HPO4/NaH2PO4 in an alternate manner. Kinetic analyses show that the phosphate-mediated inter(saccharide) interactions in terms of rate and affinity are markedly dependent on the oligosaccharide chain lengths (n), becoming more favorable with increasing n's. The novel aggregation and agglutination behaviors observed are discussed in terms of immobilizable and irreversible micelles on the basis of the cone-shaped structure of quadruple-chain amphiphile 2n having a huge saccharide pool and the efficiency of multiple hydrogen bonding therein. The unique intermolecular binding properties of compound 22 and analogues so far reported are reviewed in light of the present finding. 相似文献
919.
Kyoji Tsubakiyama Togoro Matsuo Takashi Sasaki Kenzo Yoshida Kunio Araki 《Journal of polymer science. Part A, Polymer chemistry》1979,17(6):1829-1838
Ferrocenylmethyl methacrylate (FMMA) was copolymerized with styrene (St), methyl methacrylate (MMA), and ethyl acrylate (EA) in benzene solution at 25°C by γ radiation. The reactions proceeded by a free radical mechanism, and monomer reactivity ratios were derived by the Tidwell–Mortimer method for St(M1)–FMMA(M2), r1 = 0.35 and r2 = 0.46; for MMA(M1–FMMA)(M2), r1 = 0.85 and r2 = 1.36; for EA(M1)–FMMA(M2), r1 = 0.36 and r2 = 3.03. The Q and e values of FMMA determined from copolymerization with St were 0.97 and 0.55, respectively. Terpolymerization of a MMA–FMMA–EA system based on the Alfrey–Goldfinger equations was studied. This is a typical terpolymerization system in which reactivities of the monomers obey the Q–e scheme. Comparing the results obtained here with those previously reported for other monomers, we concluded that FMMA is one of the most highly reactive monomers among alkyl methacrylates. 相似文献
920.
We have described the synthesis of the cyclometalated trihydride ditantalum(V) complexes supported by the aryloxide tridentate ligand. According to variable-temperature NMR studies, these dimers could provide a masked form of Ta(IV)-Ta(IV) and/or Ta(III)-Ta(III). In addition, these complexes were found to undergo hydrodeoxygenation of the aryloxide ligand. 相似文献