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991.
Hiroaki Saito Kousuke Inoue Keiji Matsumoto Makoto Tadokoro Yukio Nakamura 《Journal of Cluster Science》1998,9(2):145-164
The oxidative addition reaction of 2,6-bis(bromomethyl)pyridine to Ru3(CO)12 gave scarcely soluble {Ru2Br2(-Q)(CO)4}
n
, 1, [Q=C5H3N-2-C(O)CH2-6-CH2] or a mixture of 1 and the mononuclear complex RuBr(Q)(CO)3, 2, [Q=C5H3N-2-C(O)CH2-6-CH2Br] according to the reactant's mole ratio. Further reactions of 1 with some N- and P-donor ligands (L) afforded readily soluble dinuclear complexes, Ru2(-Br)(-Q)Br(CO)
n
(L)
m
[n=4, m=1, L=PPh3
3a, or py 3b; n=3, m=2, L=PPh3
5a, or PPh2(o-tolyl) 5b]. In this paper, the characterization of these products by the elemental analyses and the spectroscopic methods are described. The X-ray crystal structures of Ru2(-Br) (-Q)Br(CO)4(PPh3)(MeOH), 4, which was obtained by crystallization of 3a from MeOH, and of 5a · (2CHCl
3
) are also described. Each of the metal atoms in 4 has a distorted octahedral coordination, while in 5a · (2CHCl
3
) one metal atom takes a distorted octahedral geometry and the other pseudooctahedral, which is completed by presenting a Ru ··· Br secondary bonding interaction. 相似文献
992.
A new methodology for oligosaccharide combinatorial library synthesis using a special hydroxy protecting group, the uni-chemo hydroxy protection (UCHP) group, was developed. The UCHP group was composed of oligomeric amino acid derivatives. The amino terminals of UCHP groups were protected by either Boc or Fmoc groups. By using these two types of UCHP, five kinds of trigalactoses [Galβ1-3Galβ1-3Gal, Galβ1-3(Galβ1-4)Gal, Galβ1-4Galβ1-3Gal, Galβ1-3Galβ1-4Gal, and Galβ1-4Galβ1-4Gal] were successfully synthesized on a solid support as a model of oligosaccharide combinatorial library. Each step of all reactions was also successfully monitored using a combination of two colorimetric tests, chloranil and methyl red-DIC. 相似文献
993.
Tetsuo Suami Yoshimasa Fukuda Junji Yamamoto Yoshihiko Saito Masatoki Ito Shigeru Ohba 《Journal of carbohydrate chemistry》2013,32(1):9-19
Abstract A higher-carbon carbohydrate, a derivative of undecose has been synthesized by the potassium fluoride-catalyzed addition of a nitro sugar to a sugar aldehyde. The addition of methyl 5-de-oxy-2,3-O-isopropylidene-5-nitro-β-D-ribofuranoside to methyl 2-benzyloxycarbonylamino-2-deoxy-3,4-O-isopropylidene-α-D-galacto-dialdopyranoside-(1, 5) yielded a single diastereomer of the nitro undecose derivative. The absolute configuration of two chiral centers of the derivative has been established by the X-ray crystal structure analysis. 相似文献
994.
Mizuno K Hata K Saito T Ohshima S Yumura M Iijima S 《The journal of physical chemistry. B》2005,109(7):2632-2637
We have studied the compatibility of various catalysts for ethylene and ethanol chemical vapor deposition (CVD) syntheses of single-walled carbon nanotubes (SWNTs) on Si substrates. A strong selectivity between the catalyst elemental species and carbon source was found; SWNT yield for Fe (Co) catalysts was much higher for ethylene (ethanol) CVD than for ethanol (ethylene) CVD. This strong and completely opposite selectivity implies significantly different SWNT growth mechanisms for ethanol and ethylene CVD on Si substrates. 相似文献
995.
996.
Kitajima M Fujii N Yoshino F Sudo H Saito K Aimi N Takayama H 《Chemical & pharmaceutical bulletin》2005,53(10):1355-1358
Two new monoterpene glucosides, demethylsecologanol and 3'-O-glucosylsenburiside II, were isolated from Ophiorrhiza liukiuensis (Rubiaceae) together with 23 known compounds, including camptothecins and beta-carboline-type alkaloids. Their structures were determined by spectroscopic analysis. 相似文献
997.
Designed ferromagnetic, ferroelectric Bi(2)NiMnO(6) 总被引:1,自引:0,他引:1
Azuma M Takata K Saito T Ishiwata S Shimakawa Y Takano M 《Journal of the American Chemical Society》2005,127(24):8889-8892
A newly designed ferromagnetic, ferroelectric compound, Bi(2)NiMnO(6), was prepared by high-pressure synthesis at 6 GPa. The crystal structure, as determined by synchrotron X-ray powder diffraction, is a heavily distorted double perovskite with Ni(2+) and Mn(4+) ions ordered in a rock-salt configuration. The presence of 6s(2) lone pairs of Bi(3+) ions and the covalent Bi-O bonds give ferroelectric properties with T(CE) of 485 K, while -Ni(2+)-O-Mn(4+)-O-Ni(2+)- magnetic paths lead to a ferromagnetism with T(CM) of 140 K. This simple material design to distribute two magnetic elements with and without e(g) electrons on B sites of Bi- and Pb-based perovkites can be applied to other Bi(2)M(2+)M'(4+)O(6) and Pb(2)M(3+)M'(5+)O(6) systems to search for newer ferromagnetic ferroelectrics. 相似文献
998.
Aoki S Matsuo Y Ogura S Ohwada H Hisamatsu Y Moromizato S Shiro M Kitamura M 《Inorganic chemistry》2011,50(3):806-818
999.
Yutaka Saito Yukiko Inden-Okazaki Shoko Wada-Yano Atsuko Kanetsuna Kei-Ichi Miyazaki Masaki Mifune Yoshimasa Tanaka Hideki Okuda 《Analytica chimica acta》1985
A simple and sensitive method for assay of human serum albumin (5–80 μg) is based on binding of chrome azurol S by the albumin and determination of the bound dye spectrofluorimetrically. The method is sufficiently sensitive for application to spinal fluid (20–100 μl). 相似文献
1000.
New method for the synthesis of secondary carboxamides of type, R2NHCOR1, which utilizes 2-methyl-2-oxazoline as a carboxamide building block and various halides, R2X, has been developed. 相似文献