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71.
A variety of polysubstituted 1H-indenes can be prepared through the copper-catalyzed arylative cyclization of simple arylalkynes with commercially available aromatic sulfonyl chlorides that function as an aryl group donor. The reaction tolerates a broad range of functional groups, including bromide and iodide, nitrile, ketone, and nitro groups. The reaction allowed the synthesis of polycyclic aromatic hydrocarbons, such as a bis(indene), indacene, and fused polyarene derivatives, some of them showing strong fluorescence in solution and the solid state. 相似文献
72.
Eiichi Masumoto Hiroshi Maruoka Fumi Okabe Sho Nishida Yuki Yoshimura Toshihiro Fujioka Kenji Yamagata 《Journal of heterocyclic chemistry》2011,48(1):96-104
Dihydropyridazinones 4a , 4b , N‐substituted dihydropyrazoles 5b , 5c , 5d , and O‐substituted pyrazoles 6a , 6b , 6c , 6d have been synthesized starting from spirocyclopropanepyrazole derivative 2 . Treatment of 2 with α‐chloro esters, e.g., methyl chloroacetate, ethyl chloroacetate, isopropyl chloroacetate, and tert‐butyl chloroacetate, in potassium carbonate/sodium iodide system caused ring opening and subsequent C‐ or N‐attack nucleophilic substitution to give the corresponding dihydropyridazinones 4a , 4b and N‐substituted dihydropyrazoles 5b , 5c , 5d . On the other hand, in the absence of sodium iodide, O‐substituted pyrazoles 6a , 6b , 6c , 6d were obtained from 2 via an O‐attack nucleophilic substitution. J. Heterocyclic Chem., 2011. 相似文献
73.
Ulmann PA Tanaka H Matsuo Y Xiao Z Soga I Nakamura E 《Physical chemistry chemical physics : PCCP》2011,13(47):21045-21049
A [70]fullerene-benzodifuranone acceptor dyad synthesized by a Ag?-mediated coupling reaction was used to construct a thin-film organic solar cell. The fullerene and the benzodifuranone dye in the dyad have close-lying LUMO levels in the range of 3.7-3.9 eV, so that energy transfer from the dye to the fullerene can take place. A p-n heterojunction photovoltaic device consisting of a tetrabenzoporphyrin and a [70]fullerene-benzodifuranone dyad showed a weak but discernible contribution from light absorption of the dyad to the photocurrent under both a positive and a negative effective bias. These results indicate that the benzodifuranone moiety attached to the acceptor contributes to light-harvesting by energy transfer. 相似文献
74.
The effect of protonation to formanilides was studied by measurements of 13C-NMR chemical shifts in CDCl3 and methanesulfonic acid. It was found that the 13C shift of the ring carbon, to which the amide group is attached, exhibits an upfield shift by the protonation, whereas the peaks of the rest of ring carbons and carbonyl carbon shift downfield. The protonation-induced shifts of the ring carbons were found to be roughly correlated with the differences of the total electron densities between formanilides and their monocations. From the comparison between the protonation-induced shifts and the differences of the total electron densities at the carbons, especially at the carbonyl carbon, it is suggested that N-protonation is partly involved, although O-protonation seems to be dominant. 相似文献
75.
76.
We consider a problem of allocating indivisible objects when agents may desire to consume more than one object and no monetary
transfers are allowed. We are interested in allocation rules that satisfy desirable properties from an economic and social
point of view. In addition to strategy-proofness and Pareto efficiency, we consider consistency and two solidarity properties
(replacement-domination and population-monotonicity). In most of the cases, these properties are satisfied only by serially
dictatorial rules.
Received: November 1999/Final version: December 2001 相似文献
77.
Xiao Hui SU Gang LI Rui Sen LIN Eiichi KIKUCHI Masahiko MATSUKATA 《中国化学快报》2006,17(7):977-980
Zeolite membrane is an important category of inorganic membranes with many advantages such as thermal and chemical stability, high mechanical strength as well as the unique pore structure of molecular dimension. Up to now, many types of zeolite including … 相似文献
78.
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80.
Masahito Ochiai Munetaka Kunishima Kenzo Sumi Yoshimitsu Nagao Eiichi Fujita Masao Arimoto Hideo Yamaguchi 《Tetrahedron letters》1985,26(37):4501-4504
New general methods for the synthesis of alkynyl(phenyl)iodonium tetrafluoroborate 2 from alkynyltrimethylsilanes 1 utilizing the combination of iodosylbenzene and triethyloxonium tetrafluoroborate or boron trifluoride etherate were developed. The medium effect observed in the reaction was also discussed. 相似文献