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41.
The reactions of 2,4-diaryl-6-tert-butylnitrosobenzenes with 2,2'-azobis[2-(methoxycarbonyl)propane] (5a), 2,2'-azobis(2-cyano-4-methylpentane) (5b), and 2,2'-azobis(2-cyano-4-methyl-4-methoxypentane) (5c) in refluxing benzene gave stable N-tert-alkoxy-2,4-diaryl-6-tert-butylphenylaminyls, which were successfully isolated as radical crystals in 13-52% yields after column chromatography. The radical yields depended on the reaction time and the molar ratio of azo compounds to nitroso compounds. In the same manner, acetyl- and cyano-group-carrying N-tert-alkoxyarylaminyls were generated by the reaction of 2-phenyl-4-(4-acetylphenyl)-6-tert-butylnitrosobenzene and 2-phenyl-4-(4-cyanophenyl)-6-tert-butylnitrosobenzene with 5a and 5b, and they were isolated as radical crystals. X-ray crystallographic analyses were performed for two radicals, and their molecular structures were discussed in detail. The magnetic properties were measured for the two isolated radicals with SQUID in the temperature range 1.8-300 K. One radical showed a weak ferromagnetic interaction (theta = 0.2 K) between the radicals, and the other showed a weak antiferromagnetic interaction (theta = -3.8 K). The ferromagnetic interaction was analyzed based on the X-ray crystallographic structure. 相似文献
42.
The reaction of internal alkynes 1 with CO and pyridin-2-ylmethanol (2) in the presence of Rh(4)(CO)(12) results in a double-hydroesterification leading to 1,4-dicarboxylate esters 3. The reaction does not proceed via two consecutive hydroesterifications of alkynes, but the intermediacy of ketene intermediates is proposed. The coordination of the pyridine nitrogen in 2 to rhodium is essential for the reaction to proceed. [reaction: see text] 相似文献
43.
Shigeo Kusuoka Kazumasa Kuwada Yozo Tamura 《Probability Theory and Related Fields》2010,147(3-4):649-674
The large deviation principle for stochastic line integrals along Brownian paths on a compact Riemannian manifold is studied. We regard them as a random map on a Sobolev space of 1-forms. We show that the differentiability order of the Sobolev space can be chosen to be almost independent of the dimension of the underlying space by assigning higher integrability on 1-forms. The large deviation is formulated for the joint distribution of stochastic line integrals and the empirical distribution of a Brownian path. As the result, the rate function is given explicitly. 相似文献
44.
45.
Four formyl-group-carrying thioaminyl radicals were generated, and one radical could be isolated as radical crystals. Magnetic susceptibility measurements of the isolated radical showed a ferromagnetic regular linear-chain interaction of 2J/k(B) = 3.2 K, which was explained in terms of the X-ray crystallographic results. 相似文献
46.
Two N-tert-butoxy-2,6-diaryl-4-(4-pyridyl)phenylaminyls (1) and three N-tert-butoxy-2,6-diaryl-4-(1H-imidazol-1-yl)phenylaminyls (2) were prepared by the reaction of the lithium salts of the corresponding anilines with tert-butyl peroxybenzoate. Although 1 could not be isolated as radical crystals, 2 was successfully obtained as red crystals. The X-ray crystallographic analysis and magnetic susceptibility measurements were performed for one isolated radical. 相似文献
47.
The treatment of aryl-1-alkynes, such as 4-aryl-1-butyne, 5-aryl-1-pentyne, and 6-aryl-1-hexyne, with catalytic amounts of transition metal chlorides, such as PtCl(2) and [RuCl(2)(CO)(3)](2), at 80 degrees C in toluene results in cycloisomerization to give dihydronaphthalenes or dihydrobenzocycloheptenes, in which the cyclization mode is dependent on the length of the tethers. The reaction is limited to substrates containing terminal alkynes. A key step of the reaction is the intramolecular interception by an aromatic ring of the vinylmetal complex 2, which contains a cation center at the beta-position, generated from the electrophilic addition of transition metal halides toward an alkyne. The more electron-rich aryl systems are more reactive. 相似文献
48.
Chatani N Inoue H Kotsuma T Murai S 《Journal of the American Chemical Society》2002,124(35):10294-10295
The skeletal reorganization of enynes is achieved by the presence of GaCl3 as the catalyst. This reaction demonstrates the first example of the skeletal reorganization of enynes catalyzed by typical metal complexes. The process is simple and provides a diverse range of enynes in good to high yields. The reaction of enynes bearing a monosubstituent at the terminal olefinic carbon proceeds in a stereospecific manner with respect to the geometry of the olefin moiety. Enynes, bearing two substituents at the olefinic terminal carbon, undergo an efficient skeletal reorganization, these substrates having been known to be unsuitable substrates for the skeletal reorganization of enynes. 相似文献
49.
Yozo Miura Hiroyuki Dote 《Journal of polymer science. Part A, Polymer chemistry》2005,43(16):3689-3700
Dendritic multifunctional macroinitiators having 12 TEMPO‐based alkoxyamines were prepared by the reaction of a benzyl alcohol having 4 TEMPO‐based alkoxyamines with 1,3,5‐tris[(4‐chlorocarbonyl)phenyl]benzene and 1,3,5‐tris(4‐isocyanatophenyl)benzene. Using the dodecafunctional macroinitiators, TEMPO‐mediated radical polymerizations of styrene (St) were carried out at 120 °C, and 12‐arm star polymers ( star‐12 ) with narrow polydispersities of Mw/Mn = 1.06–1.26 were obtained. To evaluate the livingness for the TEMPO‐mediated radical polymerizations of St, hydrolysis of the ester bonds of the 12‐arm star polymers and subsequent SEC measurements were carried out. Furthermore, using star‐12 as the macroinitiator, TEMPO‐mediated radical polymerization of 4‐vinylpyridine (4‐VP) was carried out, and well‐defined poly(St)‐b‐poly(4‐VP) 12‐arm star diblock copolymers with Mw/Mn = 1.18–1.19 were obtained. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3689–3700, 2005 相似文献
50.
Hideto Kakida Yozo Chatani Hiroyuki Tadokoro 《Journal of Polymer Science.Polymer Physics》1976,14(3):427-435
The crystal structure of poly(m-phenyulene isophthalamide) was determined by x-ray analysis. The triclinic cell, with a = 5.27 Å, b = 5.25 Å, c (fiber axis) = 11.3 Å, α = 111.5°, β = 111.4° and γ = 88.0° and space group P1, contains one monomeric unit. The crystal density is 1.47 g/cc. The molecules in the crystal are contracted by 1 Å per monomeric unit from the fully extended conformation, and the planes of the benzene rings and adjacent amide groups make angles of about 30°. The crystal is composed of molecular chains connected by N? H···O hydrogen bonds along the a and b axes forming a “jungle gym” network structure. The low tensile modulus of this polymer as compared with that of poly(p-phenylene terephthalamide) is attributed to the contracted molecular conformation. 相似文献