- A new porous organic polymer containing Tr?ger's base units: Evaluation of the catalytic activity in Knoevenagel condensation reaction
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The classic Tr?ger's base polymerization of a diamine and dimethoxymethane with trifluoroacetic acid as catalyst generated a Tr?ger's base-type polymer (TBP), which exhibited the absolute insolubility in a variety of organic solvents because of its highly aggregated model. A new porous organic polymer was obtained by a simple Tr?ger's base polymerization reaction between a diamine and formaldehyde in the form of acetal in the presence of trifluoroacetic acid as catalyst. Tr?ger's base-type polymer (TBP) resulted insoluble in a wide range of organic solvents due to its rigid and aromatic structure. TBP was characterized spectroscopically (FT-IR), thermally and morphologically. As result, a thermostable and amorphous polymer bearing pores ranging between 50 and 300 nm and macro-voids of up to 12 μm was obtained. Due to the insolubility of the TBP, it was tested as a metal-free heterogeneous catalyst in the Knoevenagel condensation reaction, showing a high efficiency. For this, the optimal catalyst load, reaction time and reuse of the catalyst were studied using benzaldehyde and malononitrile as substrates. Furthermore, aldehydes with variable chain sizes and ethyl cyanoacetate replacing malononitrile were tested as substrate with a high percent of conversion (97–99%).
- Coll, Deysma,Escalona, Néstor,Jessop, Ignacio A.,Martin-Trasanco, Rudy,Niebla, Vladimir,Ortiz, Pablo A.,Pérez, Edwin,Rodríguez-González, Fidel E.,Tagle, Luis H.,Terraza, Claudio A.,Tundidor-Camba, Alain,Velázquez-Tundidor, M. V.
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- Heterocyclic compound and organic electroluminescent device using the same
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Disclosed is an organic electroluminescent device (organic EL device) which is improved in luminous efficiency, fully secured of driving stability, and simple in structure and also disclosed is a heterocyclic compound useful for the said device. Specifica
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- Aminodibenzodioxin derivative and organic electroluminescent using the same
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This invention relates to a highly reliable material for an organic electroluminescent element exhibiting high luminance, high luminous efficiency, little deterioration in emission, and suitability for use and storage at high temperatures and to an organi
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Page/Page column 20-21
(2009/10/22)
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- HETEROCYCLIC COMPOUND AND ORGANIC ELECTROLUMINESCENT DEVICE USING SAME
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Disclosed is an organic electroluminescent device (organic EL device) of simple structure which is improved in luminous efficiency and sufficiently secured in driving stability. Also disclosed is a heterocyclic compound used for such an organic electrolum
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Page/Page column 16
(2008/06/13)
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- ELECTRON TRANSFER AS ELEMENTARY STAGE IN ELECTROPHILIC NITRATION OF DIBENZO-p-DIOXIN
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The formation of the radical-cation of dibenzo-p-dioxin in the reaction of dibenzo-p-dioxin with nitrating agents was recorded by the ESR method and electronic spectroscopy.Photometric investigation of the reaction of this compound with nitric acid in trifluoroacetic acid showed that the nature and composition of the products depend on the molar ratio of nitric acid and the substrate.With a deficiency of nitric acid the radical-cation or its mixture with the dinitro derivatives of dibenzo-p-dioxin are formed, whereas with an excess of nitric acid only a mixture of the dinitro compounds is formed.Analysis of these facts led to the conclusion that the nitration of dibenzo-p-dioxin with nitric acid in trifluoroacetic acid includes the stage of one-electron oxidation of the initial aromatic compound.
- Morkovnik, A. S.,Belinskii, E. Yu.,Dobaeva, N. M.,Okhlobystin, O. Ya.
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p. 328 - 335
(2007/10/02)
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- The Smiles Rearrangement of 2-Aryloxy-5-nitrophenoxides. Attempted Routes to Benzoxirens and Tribenzotrioxonins
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Formation of dibenzo-p-dioxins by the pyrolysis of 2-halogenophenoxides does not appear to involve intermediate benzoxirens.Thermal self-condensation to potassium 2-bromo-5-nitrophenoxide (1b) gave a mixture of 2,7- and 2,8-dinitrobenzo-p-dioxins (6d) and (6e).The mechanism of formation of the 2,8-isomer (6e) is shown to involve Smiles rearrangement of potassium 2-(2-bromo-5-nitrophenoxy)-5-nitrophenoxide (9a).Further examples of Smiles rearrangements of 2-aryloxy-5-nitrophenoxides and an attempted synthesis of the tribenzotrioxonin derivatives (16) are described.
- Ramsden, Christopher A.
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p. 2456 - 2463
(2007/10/02)
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