• 제목/요약/키워드: acetylacetone

검색결과 54건 처리시간 0.021초

Supercritical Drying에 의한 $TiO_2-SiO_2$ 이성분계 Aerogel의 제조 및 그 특성분석 (A Study on the Preparation and Characterization of $TiO_2-SiO_2$ Aerogels by Supercritical Drying)

  • 김창은;이종혁;김구대;이해욱
    • 한국세라믹학회지
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    • 제31권6호
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    • pp.623-628
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    • 1994
  • TiO2-SiO2 homogeneous sol was prepared by means of complexing titanium iso-propoxide with acetylacetone. Crack-free, monolithic binary TiO2-SiO2 aerogels were obtained by evacuating the solvent under the pressure of 2,200 psi at 28$0^{\circ}C$, which was determined as a supercritical condition. The microstructure of the binary aerogels was observed to be finer and more homogeneous as the Ti content decreased. The microstructure was related to the optical transition of aerogels from opaque to transluscent.

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환경신뢰성이 확보된 투명전도성 필름을 위한 비공유 걸합에 의한 단일벽 탄소나노튜브의 $TiO_2$ 코팅 (Noncovalent Titania Wrapping of Single-Walled Carbon Nanotubes for Environmentally Stable Transparent Conductive Thin Films)

  • 한중탁;김준석;;정희진;정승열;이건웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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    • pp.20-20
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    • 2010
  • We present a simple process for the fabrication of high performance transparent conducting films that contain single-walled carbon nanotubes (SWCNTs) noncovalently coated with an ultrathin titania layer. The hydrophobic interactions between nanotube surfaces and the acetylacetone (acac) ligands used to stabilize the $TiO_2$ precursor provide an interesting alternative method for noncovalently coating the SWCNTs with a titania layer. The ultrathin titania layer on SWCNTs prevented the oxidation of functionalized SWCNTs at high temperatures, and protected against water molecule absorption.

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환경신뢰성이 확보된 투명전도성 필름을 위한 비공유 결합에 의한 단일벽 탄소나노튜브의 $TiO_2$ 코팅 (Noncovalent Titania Wrapping of Single-Walled Carbon Nanotubes for Environmentally Stable Transparent Conductive Thin Films)

  • 한중탁;김준석;정희진;정승열;이건웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.279-279
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    • 2010
  • We present a simple process for the fabrication of high performance transparent conducting films that contain single-walled carbon nanotubes (SWCNTs) noncovalently coated with an ultrathin titania layer. The hydrophobic interactions between nanotube surfaces and the acetylacetone (acac) ligands used to stabilize the $TiO_2$ precursor provide an interesting alternative method for noncovalently coating the SWCNTs with a titania layer. The ultrathin titania layer on SWCNTs prevented the oxidation of functionalized SWCNTs at high temperatures, and protected against water molecule absorption.

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새로운 Pyrazolylquinoxaline류의 합성 (Synthesis of Novel Pyrazolylquinoxalines)

  • 김호식;곽삼탁
    • 대한화학회지
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    • 제44권3호
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    • pp.229-236
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    • 2000
  • 6-Chloro-2-hydrazinoquinoxaline4-oxide(10)를 아세틸아세톤 또는 디벤조일메탄과 반응시켜 분자내 고리화반응에 의한 6-chloro-2-(3,5-disubstituted pyrazol-1-yl) quinoxaline 4-oxide류(11)를 합성하였다. 화합물 11을 phosphoryl chloride로 염소와 반응시켜 3,6-dichloro-2-(3,5-disubstituted pyrazol-1-yl)quino-xaline류(12)를 합성한 다음 hydrazine hydrate 반응시켜 6-chloro-3-hydrazino-2-(3,5-disubstituted pyrazol-1-yl)quinoxaline류(13)를 합성하였다. 화합물 13을 치환 벤즈알데히드류, benzenesulfonyl chloride, 치환 benzoyl chloride류 및 acyl chlorid 류와 반응시켜 새로운 pyrazolylquinoxaline류(14-17)를 각각 합성하였다.

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목재 및 철재가구중의 유해물질 방출에 관한 연구 (A Study on the Emission of Hazardous Volatile Compounds in Wood and Steel Furniture)

  • 김선태;박경수;김병억;우순형
    • 분석과학
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    • 제11권3호
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    • pp.194-201
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    • 1998
  • 목재 및 철재기구로부터 방출된 포름알데히드를 증류수에 흡수시키고 아세틸아세톤법을 사용하여 정량하였다. 실온에서 시간 경과에 따른 방출량의 변화를 보았다. 50 mL 병에 목재 및 철재를 넣고 방출된 휘발성 유기 물질을 ion-trap GC-MS를 이용하여 정량하였다.

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Autoxidation of Cycloalkenes by the System “Molecular Oxygen-bis(acetylacetonato) Cobalt (II) Complex-butyraldehyde”

  • Fang, Zhao;Tang, Rui-Ren;Zhang, Rui-Rong;Huang, Ke-long
    • Bulletin of the Korean Chemical Society
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    • 제30권10호
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    • pp.2208-2212
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    • 2009
  • Oxidation of cycloalkenes with $O_2$ promoted by heterogeneous bis(acetylacetonato) cobalt (II) complex catalyst which can be recycled has been performed under mild conditions. It was found that $\beta$-ionone, cyclohexene, 1-methylcyclohexene, and $\alpha$-ionone were efficiently oxidized with $O_2$ in the presence of Co (II) complex and butyraldehyde at $55\;{^{\circ}C}$. A simple treatment of the resulting products led to epoxides as predominant products and a small amounts of allylic oxides, the chemoselectivity for the former being 82.1 - 90.8% with a 70.6 - 98.6% substrate conversion. On the other hand, oxidation of 1-phenylcyclohexene, 1-cyclohex-1-enylethan-1-one, $\alpha$-pinene, and $\beta$-pinene gave allylic oxides as major products.

芳香族 디히드라진에 關한 硏究 (第2報). 파라페닐렌디히드라진과 디카르보닐 化合物과의 縮合反應 (Studies on the Aromatic Dihydrazines (Ⅱ). Condensation Reaction Between p-Phenylenedihydrazine and Dicarbonyl Compounds)

  • 이우영
    • 대한화학회지
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    • 제20권6호
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    • pp.500-506
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    • 1976
  • 파라페닐렌디히드라진(PPDH)과 디카르보닐化合物을 반응시켜서 생기는 縮合生成物들의 構造를 밝혔다. 아세틸아세톤과의 반응에서는 고리화합물인 1,1'-p-페닐린-bis-3-메틸-5-피라졸론이 얻어졌으며, 디아세틸과의 반응에서는 역시 고리화합물인 1,1'-p-페닐렌-bis-메틸-5-피라졸론이 얻어졌으며, 디아세틸과의 반응에서는 디아세틸 p-페닐렌디히라존이 生成되었다. 그 밖의 디카르보닐화합물에서 얻은 축합생성물은 불안정하여 구조결정이 어려웠다.

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A Facile One-pot Synthesis of Fused 2-Thiouracils: Dipyrimidinopyridine, Pyrazolopyrimidine and Pyridazinopyrimidines

  • Youssif, Shaker;EI-Bahaie, Said;Nabih, Esam
    • Bulletin of the Korean Chemical Society
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    • 제24권10호
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    • pp.1429-1432
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    • 2003
  • A novel fused thiouracil containing a heterocyclic ring system, dipyrimidinopyridine (3), has been prepared through the cyclization of compound 2. Compound 2 was formed by the formylation of 6-amino-2-thiouracil 1, pyrazolopyrimidines 8-10 via the heating of 6-arylhydrazono-2-thiouracils 5-7, compound 11, using Vilsmeier reagent with compound 4, pyrazolylpyrimidine 12, indolodiazinopyrimidine 14 and pyridazinopyrimidine 15. Pyridazino-pyrimidine 15 was formed by the condensation of compound 4 with acetylacetone, isatin and benzyl, respectively.

Structural Investigation of the Hydrolysis-Condensation Process of Modified Titanium Isopropoxide

  • Jung, M. W.;Oh, H. J.;Yang, J. C.;Shul, Y. G.
    • Bulletin of the Korean Chemical Society
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    • 제20권12호
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    • pp.1394-1398
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    • 1999
  • The structures of modified Ti$(OPr^i)_4$ with chelating ligands (L) such as ethylacetoacetate (Etac), acetylacetone (Acac) and methylacetoacetate (Mtac) were identified by using IR, ¹H NMR and $^13C$ NMR spectroscopies, and the octahedral structure was confirmed after modification. The pre-edge peaks of XANES spectra of modified metal alkoxides also denoted the mixture of five-fold and six-fold structures. The EXAFS fitting results showed the local structure around Ti atom after alkoxide modification. The hydrolysis-condensation rates of modified Ti alkoxide with organic additives were investigated by ¹H NMR spectroscopy. The Ti$(OPr^i)_4$ modified by Acac was less reactive toward hydrolysis-condensation reaction than those modified by the other alkoxides, which can be attributed to the stable ligand structure between Ti$(OPr^i)_4$ and Acac. The small particle size of modified Ti$(OPr^i)_4$ sol was obtained when Acac was employed.

Studies on Synthesis and Heterocyclisation Reactions of Michael Products and Formation of New 1, 4-Thiazine Quinoxaline Derivatives

  • Mahgoub, S.A.
    • Archives of Pharmacal Research
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    • 제13권4호
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    • pp.319-324
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    • 1990
  • Synthesis of $\alpha$-piperidino and $\alpha$-morphelino styryl quinoxalinone 2f, 2g respectively by facile one step method is reported. The Michael adducts (3a-d) obtained by the interaction of 2-styryl-2 (1H) quinoxalinone (2) and ethylacetoacetate have been treated with resorcino and hydroxylamine separately. With resorcinol the chromones (4) are obtained whereas with ydroxylamine isoxazoles (6) are the products. Michael addition of acetylacetone to 2 leads to 3-[1'-aryl-2'-(2'-hydroxy-3'-quinoxalinyl)ethyl]-2, 4-pentanediones (5) which undergo cyclisation with hydroxylamine to give isoxazoles (7). Addition of thiopenol and thioglycolic acid to 2 gives 3-$\alpha$[$\beta$-(phenyl)-$\beta$-(plenylthio)]ethyl-2(1H)-quinoxalinone (8) and 3-$\alpha$-[$\beta$-phenyl)-$\beta$-(hydroxycarbonylmethylithio)]-ethyl-2(1H)-qui noxalinone (9) respectively. 2-Bromomethyl-2(1H)-quinoxalinone (1b) reacts with thioglycolic acid to gives S-[2 (1H)-oxoquionoxaline-3-yl-methyl] mercaptoacetic acid (10) which on cyclisation with acetic anhydride/pyridine affords 1, 2, 5, 6-tetrahydro [1, 4]thiazino[4, 3-a] quinoxaline-1, 6-dione (11).

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