• 제목/요약/키워드: Benzil

검색결과 18건 처리시간 0.03초

Sulphanilic Acid촉매하에서 벤질/벤조인과 방향족 알데히드로부터 2,4,5-Triarylimidazoles의 간편한 One-pot 합성 (Sulphanilic Acid Catalyzed Facile One-pot Synthesis of 2,4,5-Triarylimidazoles From Benzil/Benzoin and Aromatic Aldehydes)

  • Mohammed, A.F.;kokare, N.D.;Sangshetti, J.N.;Shinde, D.B.
    • 대한화학회지
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    • 제51권5호
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    • pp.418-422
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    • 2007
  • Sulphanilic Acid 촉매를 사용한 벤조인 또는 벤질, 초산암모늄 그리고 방향족 알데히드의 축합반응을 통한 간단하고 높은 수율의 2,4,5-Triarylimidazoles의 One-pot 합성에 대한 보고 값싼 가격의 촉매,높은 수율 그리고 짧은 반응 시간은 제시된 방법의 장점이다.

L-Proline as an Efficient Catalyst for the Synthesis of 2,4,5-Triaryl-1H-Imidazoles

  • Shitole, Nana V.;Shelke, Kiran F.;Sonar, Swapnil S.;Sadaphal, Sandip A.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Bulletin of the Korean Chemical Society
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    • 제30권9호
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    • pp.1963-1966
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    • 2009
  • L-Proline has been found to be an efficient organocatalyst for one-pot synthesis of 2,4,5-triaryl substituted imidazole by the reaction of an aldehyde, a benzil and an ammonium acetate. The short reaction time and excellent yields making this protocol practical and economically attractive.

Ester Linkage를 함유한 Bismaleimide의 합성과 감광특성 (Synthesis and Photocharacteristics of Bismaleimide Containing Ester Linkage)

  • 김상민;김태호
    • 공업화학
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    • 제8권2호
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    • pp.147-153
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    • 1997
  • N-(p-carboxyphenyl)maleimide의 염소화물을 N-(p-hydroxyphenyl)maleimide와 반응시켜 중심에 에스테르 결합을 가지고 있는 bismaleimide(BISMI)를 합성하였다. 합성된 BISMI의 감광특성을 확인한 결과 사용된 benzil dimethyl ketal 광개시제의 농도와 자외선 조사량을 증가시킴에 따라 BISMI의 점도가 증가하는 경향을 보였다 또한 BISMI의 잔막수율의 변화와 화상형성능력 및 최소선폭을 검토하였다.

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PHOTOCHEMICAL REACTIONS OF AROMATIC $\alpha$-DIKETONES

  • Kim, Sung Sik
    • Journal of Photoscience
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    • 제1권2호
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    • pp.123-126
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    • 1994
  • Irradiation of aromatic $\alpha$-diketones, such as benzil, 4,4'-dimethylbenzil, 4-chlorobenzil, 4,4'-diisopropylbenzil, 3,3,'-dimethylbenzil, in methanol gives rise to xanthone derivatives, in addition to $\alpha$-hydroxyketones. Irradiation of 4,4'-dibromobenzil, 2,2'-pyridil, 2,2'-naphthil and 9,9'-anthril yields only $\alpha$-hydroxyketones, whereas 4,4'-dimethoxybenzil yields methyl 4-methoxybenzoate.

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Cr(Ⅲ) Complexes of Tetraazamacrocycles Derived from $\alpha$-Diketones and Diaminoalkanes

  • Rai, Pramod K.;Gupta, Ajay K.;Prasad, Raghu N.
    • Bulletin of the Korean Chemical Society
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    • 제14권2호
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    • pp.179-183
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    • 1993
  • Template condensation of ${\alpha}$-diketones such as 2,3-butanedione or benzil with diaminoalkanes such as 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, 1,8-diaminooctane or 1,12-diaminododecane in the presence of Cr(III) results in the formation of complexes of the type $[CrI,X_2]X$ (where L = tetraazamacrocycle having 12 to 32-membered ring and $X={NO_3}^- or Cl^-).$ The complexes have been characterized by elemental analyses, magnetic measurements and IR and diffuse reflectance spectra.

Photochemical Reductions of Benzil and Benzoin in the Presence of Triethylamine and TiO? Photocatalyst

  • Park, Joon-Woo;Kim, Eun-Kyung;Koh Park, Kwang-Hee
    • Bulletin of the Korean Chemical Society
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    • 제23권9호
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    • pp.1229-1258
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    • 2002
  • This paper reports the photochemical reduction of benzil 1 to benzoin 2 and the reduction of 2 to hydrobenzoin 4 in deoxygenated solvents in the presence of triethylamine (TEA) and/or TiO2. Without TEA or TiO2, the photolysis of 1 resulted in very low yield of 2. The presence of TEA or TiO2 increased the rate of disappearance of 1 and the yield of 2, which were further increased considerably by the presence of water. The photoreduction of 1 to 2 proceeds through an electron transfer to 1 from TEA or hole-scavenged excited TiO2 followed by protonation. In the reaction medium of 88 : 7 : 2 : 3 CH3CN/CH3OH/H2O/TEA with 2.5 $㎎/m{\ell}$ of TiO2, the yield of 2 was as high as 85 % at 50 % conversion of 1. The photolysis of 2 in homogeneous media resulted in photo-cleavage to benzoyl and hydroxybenzyl radicals, which are mostly converted to benzaldehyde. The reduction product 4 is formed in low yield through the dimerization of hydroxybenzyl radicals. The addition of TEA increased the conversion rate of 2 and the yield of 4 significantly. This was attributed to the scavenging effect of TEA for benzoyl radical to produce N,N-diethylbenzamide and the photoreduction of benzaldehyde in the presence of TEA. The ratio of $(\pm)$ and meso isomers of 4 obtained from the photochemical reaction is about 1.1. This ratio is the same as that from the photochemical reduction of benzaldehyde in the presence of TEA. In the TiO2-sensitized photochemical reduction of 2, meso-4 was obtained in moderate yield. The reduction of 2 to 4 proceeds through two consecutive electron/proton transfer processes on the surface of the photocatalyst without involvement of ${\alpha}-cleavage$. The radical 11 initially formed from 2 by one electron/proton process can also combine with hydroxy methyl radical, which is generated after hole trapping of excited TiO2 by methanol, to produce 1,2-diphenylpropenone after dehydration reaction.