• Title/Summary/Keyword: phthalimide

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Photochemical Ring-Opening of Acid Anhydrides by $TiO_2$ Photocatalyst in Methanol

  • Kim, Sung-Sik;Mah, Yoon-Jung;Lee, Hye-Jong;Park, Sang-Kyu
    • Journal of Photoscience
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    • v.10 no.3
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    • pp.241-243
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    • 2003
  • Photoreactions of some carbonyl compounds with TiO$_2$ were investigated in methanol. Although 1,3-cyclohexanedione and phthalimide afforded 3-methoxy-2-cyclohexen-l-one and 3-methoxy-1-isoindolinone, respectively, acid anhydrides such as succinic, phthalic, and maleic anhydrides gave the monoesters of dicarboxylic acids in good to excellent yields, when they were irradiated on TiO$_2$ in methanol with 300 nm UV light.

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Electrical Phase Transition of Poly (4,4'-Aminotriphenylene Hexafluoroisopropylidenediphthalimide) by Photogenerated Charged Carrier Injection

  • Im, Gyu-Uk;Lee, Gyeong-Jae;Lee, Mun-Ho;Gang, Tae-Hui;Jeong, Seok-Min;Yang, Mi-Hyeon;Kumar, Yogesh
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.266-266
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    • 2013
  • We show a set-up of poly (4,4'-aminotriphenylene hexafluoroisopropylidenediphthalimide) (6F-TPA PI)/Al sample in which holes are injected by photoelectron emission process instead of direct charge carrier injection via metal electrode. In this process, an irreversible electrical phase transition of 6F-TPA PI is found in contrast to the Al/6F-TPA PI/Al structure, leading to a write-once-readmany behavior. The photoelectron spectroscopy results measured before and after the switching process revealed that the irreversible electrical phase transition of 6F-TPA PI is attributed to the chemical modification of the carbonyl group in phthalimide moiety.

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Prefluorescent-Dye-Induced Fluorescent Imaging based on Polymeric Photobase Generators

  • Chae, Kyu-Ho;Choi, Won-San;Kim, Yoo-Ho
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.177-177
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    • 2006
  • Copolymers containing oxime-urethane groups, which led to the formation of pendant amino groups photochemically, were applied to a fluorescent image-recording material through the reaction with fluorescamine, a prefluorescent dye for amino groups. This imaging method permits the fluorescent image to be erased or restored by treatment with base or acid. Copolymers containing phthalimide carbamate groups were applied to a bicolor fluorescent imaging material through the consecutive reaction with fluorescamine and rhodamine. A various colored fluorescent micropattern (green, red or red-yellow) was observed through the changes of excitation wavelength by using a conforcal microscope.

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Polyhydroxyamic Acid from 3,3′ - Dihydroxybenzidine and Pyromellitic Dianhydride as a Fire-safe Polymer

  • Park, Seung Koo;Farris, Richard J.;Kantor, Simon W.
    • Fibers and Polymers
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    • v.5 no.2
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    • pp.83-88
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    • 2004
  • In order to assess the potential of the hydroxy-containing polyamic acid (PHAA) synthesized from 3,3'-dihydroxy benzidine and pyromellitic dianhydride for a fire-safe polymer, the cyclization pathway of PHAA has been investigated using a model compound prepared from 2-aminophenol and phthalic anhydride. The reaction was monitored. by $^1{H-nuclear}$ magnetic resonance. N-(2-hydroxyphenyl) phthalamic acid is converted to N-(2-hydroxyphenyl) phthalimide at ca. 175$^{\circ}C$, showing endothermic reaction. The imide structure is rearranged to the benzoxazole structure over ca. $400^{\circ}C$. These results are similar with that of PHAA. According to pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) data, water and carbon dioxide are released during the cyclization and rearrangement reaction. One DMAc molecule is complexed with one carboxyl acid group in PHAA, which accelerates the imidization process to release more easily the flame retardant, water.

Single Electron Transfer Promoted Photocyclization Reactions of ($\omega$-Phthalimidoalkylthio) acetic Acids

  • Yoon, Ung-Chan;Lee, Sang-Jin;Oh, Sun-Wha;Cho, Dae-Won
    • Journal of Photoscience
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    • v.8 no.3_4
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    • pp.99-104
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    • 2001
  • Studies have been conducted to explore single electron transfer (SET) promoted photocyclization reactions of ($\omega$-phthalimidoalkylthio)acetic acids (alkyl=ethyl, n-propyl, n-butyl, n -hexyl and n-nonyl). Photocyclizations occur in methanol in modest yields to produce cyclized products in which phthalimide carbonyl carbon is bonded to the carbon of side chain in place of the carboxylic group. The initially formed cyclized products undergo efficient water eliminations to produce enthiol ethers in secondary ground state reactions.

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The Synthetic Potential of SET Photochemistry of Silicon-Substituted Polydonor-Linked Phthalimides

  • Yoon, Ung Chan;Mariano, Patrick S.
    • Bulletin of the Korean Chemical Society
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    • v.27 no.8
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    • pp.1099-1114
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    • 2006
  • Our studies in the area of single electron transfer (SET) photochemistry have led to the discovery of efficient processes, in which regioselective formation of carbon-centered radicals takes place by nucleophile assisted desilylation of $\alpha$-trialkylsilyl substituted ether, thioether, amine and amide centered cation radicals. The rates of bimolecular desilylation of the intermediate cation radicals exceed those of other cation radical $\alpha$-fragmentation processes (e.g.,-deprotonation). This sereves as the basis for the design of highly regioselective, SET-induced photomacrocyclization reactions of polyether, polythioether, polyamide, and polypeptide linked phthalimides. Photocyclization reactions of trimethylsilyl-terminated substrates in these families are unique in that they produce polyfunctionalized macrocyclic substances in a highly efficient and regioselective manner. In addition, our studies in this area have led to important information about the factors that govern chemical and quantum efficiencies that should be applicable to a wide variety of redox processes promoted by SET from substrates containing more than one electron donor site.

WORM Behavior of 6F-TPA PI by Hole Injection

  • Lee, Gyeong-Jae;Im, Gyu-Uk;Yang, Mi-Hyeon;Gang, Tae-Hui;Jeong, Seok-Min
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.244-244
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    • 2012
  • Polymer memory devices have attracted considerable attention because of their advantages such as low cost potential, good scalability, flexibility, simplicity in structure, and large capacity for data storage. Metal/poly (4,4'-aminotriphenylene hexafluoroisopropylidenediphthalimide) (6F-TPA PI)/metal system has been found to show an electrical bi-stable behavior. Here, we show a novel set-up of 6F-TPA PI/Al sample in which holes are injected by photoelectron emission process instead of direct charge carrier injection via metal electrode. In this process, an irreversible electrical phase transition of 6F-TPA PI is found, leading to a write-once-read-many (WORM) behavior. The photoelectron spectroscopy results measured before and after the switching process revealed that the irreversible electrical phase transition of 6F-TPA PI is attributed to the chemical modification of the carbonyl group in phthalimide moiety.

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Spectroscopic Studies of TP6F PI Switched by Hole-Injection

  • Lee, Gyeong-Jae;Im, Gyu-Uk;Kim, Dong-Min;Lee, Mun-Ho;Gang, Tae-Hui;Jeong, Seok-Min
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.297-298
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    • 2011
  • Metal/poly (4,4'-aminotriphen-ylene hexafluoroisopropylidenediphthalimide) (TP6F PI)/metal structure exhibited an electrically volatile phase transition with high (OFF) or low (ON) resistive states when voltage between electrodes swept. Here, we demonstrate a noble set-up in which holes are injected by photoelectron emission process during the voltage sweep instead of direct charge carrier injection via metal electrode, which enables direct investigation into changed electronic structures of TP6F PI both in ON and OFF states using photoemission spectroscopy methods. In the I-V measurement, TP6F PI shows a non-volatile behavior. In spectroscopic results, this non-volatile behavior is leaded from the structural modification of the O=C double bond in phthalimide of TP6F PI by hole injection.

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Dyeing Properties of Polyurethane Fiber by Novel Phthalimidyl Azo Disperse Dyes (Phthalimide계 신규 Azo dye의 Polyurethane계 섬유 염색 특성)

  • Choi, Jong-Yun;Choi, Jae-Hong
    • Textile Coloration and Finishing
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    • v.21 no.6
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    • pp.46-55
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    • 2009
  • Some phthalimidyl azo dyes containing N,N-diethyl or N,N-di($\beta$-methoxycarbonylethyl) group have been attempted to apply onto two kinds of polyurethane based materials and rationalize their dyeability and fastness comparing with those of some commercial disperse dyes. Phthalimidyl azo dye showed 66~98% of exhaustion yield at $120^{\circ}C$ by a conventional exhaust dyeing method. The dyeings were found to have a higher wash fastness with both fabrics in comparison with those of commercial dyes which indicates lower thermomigration and efficient alkali clearable properties of phthalimidyl ring and/or diester group during post-dyeing process.

Kinetics of the Formation of Nickel-Phthalocyanine (Nickel-Phthalocyanine 생성의 반응속도론적 연구)

  • Bae, Kook-Jin;Hahn, Chi-Sun
    • Journal of the Korean Chemical Society
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    • v.16 no.2
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    • pp.84-92
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    • 1972
  • A mechanism for the ring formation of nickel phthalocyanine (Ni-Pc) has been proposed based on chemical kinetics. The effect of the catalyst on the rate was examined, and ammonium molybdate has been found to be the most effective. The reaction order of the ring formation was determined to be of the 1st order over all, with only the concentration of urea affecting the rate of the ring formation. All the results including thermodynamic parameters support a conclusion that the rate-determining step seems to be the enolization of the urea-catalyst transition complex, followed by fast decomposition of the tautomeric enolized urea into ammonia and isocyanic acid. These intermediates then reacted with the phthalic anhydride to form imino and diimino-phthalimide, which condense to form nickel phthalocyanine in the presence of the nickel cation.

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