• 제목/요약/키워드: Cyclopentanone

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Pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dione의 합성 (Studies on the Synthesis of Pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dione)

  • 정의준;장세희
    • 대한화학회지
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    • 제18권6호
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    • pp.437-442
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    • 1974
  • Cyclopentanone을 출발 물질로 하여 60%의 좋은 총 수득률로 pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dion을 합성하였다. Cyclopentanone 으로부터 그의 ethylene ketal(I)을 합성하여 pyridinium bromide perbromide로서 브롬화시키고 브롬화 ketal(II)을 다시 dehydrobromination 시켜 cyclopentadienone-ethylene ketal의 dimer를 합성하였다. Ethylene ketal의 dimer(III)를 다시 가수분해시켜 dicyclopentadiene-1,8-dione(IV)을 합성하고 이 diketone(IV)을 photochemical cyclization에 의하여 pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dione(V)을 합성하였다.

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Synthesis and Absorption Spectral Properties of Bis-methine Dyes Exemplified by 2,5-Bis-arylidene-1-dicyanomethylene-cyclopentanes

  • Asiri, Abdullah Mohamed
    • Bulletin of the Korean Chemical Society
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    • 제24권4호
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    • pp.426-430
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    • 2003
  • A range of methine dyes has been synthesized by condensation of highly electronegative active methylene compound dicyanomethylenecyclopentane derived from cyclopentanone with the formyl group of substituted benzaldehydes. The electronic absorption spectroscopic properties of the dyes were investigated. In general, substituents on the aromatic aldehyde moiety have a significant effect on the visible absorption maxima of the dyes; increasing the solvent polarity also showed a pronounced effect on the absorption maxima.

Palladium Dichloro Complex Catalysed Oxidation of Cyclopentene by Dioxygen in Tetralin$^\dag$

  • Takehira, Katsuomi;Hayakawa, Takashi;Orita, Hideo;Shimizu, Masao;Oh, In-Hwan
    • Bulletin of the Korean Chemical Society
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    • 제8권4호
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    • pp.254-257
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    • 1987
  • Palladium dichloro complexes catalysed the oxidation of cyclopentene by dioxygen in tetralin solvent at ambient temperature. Cyclopentanone formed mainly together with autoxidation products from both cyclopentene and tetralin. The oxidation seems to proceed by co-oxidation mechanism, where tetralin was first oxidized to its hydroperoxide which then oxidized cyclopentene to cyclopentanone. Mechanism of the other by-products formations has been discussed.

Aliphatic Ketone과 Alicyclic Ketone의 Semicarbazone 생성반응에 관한 연구 (Studies on the Semicarbazone Formation of Aliphatic and Alicyclic Ketones.)

  • 임락빈;오양환;김용인
    • 한국응용과학기술학회지
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    • 제8권1호
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    • pp.59-67
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    • 1991
  • The reactions of semicarbazide hydrochloride with aliphatic and alicyclic ketones were studied kinetically at 15, 25, 35 and 45$^{\circ}C$ in 20% ethanol solution buffered at pH 2.9. The rate of cyclohexanone semicarbazone formation is 5.5 times as fast as that of cyclopentanone semicarbazone, while 3-pentanone semicarbazone is 4.7 times as slow as that of 2-pentanone, The activation energy of cyclohexanone, 2-pentanone, 2 hexanone, cyclopentanone, 4-methyl-2-pentanone and 3-pentanone semicarbazone formation are calculated 5.08, 7.52, 8.79, 9.59, 9.49, 11.59, respectively. It is concluded from the effect of ionic strength that the reaction is affected by not ion but neutral molecules being progressed hydrogen bond between oxygen atom of carbonyl group and hydrogen atom of acid-catalyst and concerted nucleophilic attack of free base on the carbonly compound. Dependence on pH of the rate of 2-pentanone semicarbozone formation is linear relationship below pH 4.60 and above pH 5.60. As a result of studing citric acid catalysis, second order constants increase linearly with citric acid concentration. As the catalyst concentration is varied from 0.025 to 0.10 mol/1 at pH 2.90, the rate constants increase 1.4 times, but slight increase is observed at pH 5.60. Conclusively, the rate-determining step is formation of tetrahedral interemediate below pH 4.65 and dehydration between pH 5.60 and pH 7.11. It is concluded that the formation reaction of cyclohexanone semicarbazone is faster than cyclopentanone semicarbazone due to the steric strain in the process of forming tetrahedral intermediate.

전기장에 의한 유기용액의 비등방 비선형 굴절율 (Electric Field Induced Anisotropic Nonlinear Refractive Index of Organic Solution)

  • 원영희;김용기;이종하;이현곤
    • 한국광학회지
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    • 제5권4호
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    • pp.481-486
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    • 1994
  • 높은 정전기장이 인가된 유기용액의 분자배향도를 측정하는 수단으로 z-scan방법을 사용하였다. 무게비로 0.5%의 4-dimethylamino-4'-nitrostilbene을 cyclopentanone에 녹인 혼합용액을 시료로 z-scan실험을 수행하였으며 측정된 등방비선형 굴절율 $n_{2}$값은 $1.064{\mu}m$파장에서 $-0.905\times10^{-8}\textrm{cm}^2/MW$였다. 3.45KV/nm 정전기장을 인가한 경우에 측정된 $n_{2}$의 비등방비 값은 1.34였으며 분자배향도계수 $

    _2 및

    _4$값은 0.092 및 -0.128이였다.

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Synthesis of 2,5Bis(2'-piperidymethyl)piperidine and Related Compounds

  • Hammouda, Metwally;Kandeel, Ex-el-Din;Hamama, Wafaa;Afsah, Elsayed
    • Archives of Pharmacal Research
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    • 제16권1호
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    • pp.68-70
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    • 1993
  • The triketones 3-6 were obtained by alkylation of cyclopentanone or cyclohexanone with the appropriate cycloalkanone bis-mannich base (1) or (2). Schmidt reaction of the tricketones 3-6 afforded the corresponding trcyclic lactames 7-10 respectively. reduction of 7 and 9 gave compounds 11 and 12 respectively.

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Two Phase Reduction of Carbonyl Compounds with Sodium Borohydride

  • Jin Soon Chong;Nung Min Yoon
    • 대한화학회지
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    • 제15권3호
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    • pp.117-120
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    • 1971
  • Possibility of two phase reduction of carbonyl compounds to the corresponding alcohols was studied. Thus the 0.5 M ether solutions of the representative carbonyl compounds were treated with alkaline stabilized sodium borohydride aqueous solution at room temperature. Butyraldehyde was reduced rapidly within one hr., whereas other aldehydes tested; heptaldehyde, benzaldehyde, and 1-naphthaldehyde were reduced in 6-12 hr. 2-Heptanone was reduced much slowly; 87% in 48 hr., however, acetophenone was reduced moderately; 92% in 12 hr. and cycloalkanones were reduced rapidly (cyclohexanone in 0.5 hr., and cyclopentanone in 3-6 hr.).

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Selective Reduction of Oximes to N-Monosubstituted Hydroxylamines with Lithium Borohydride

  • Cho, Byung-Tae;Seong, See-Yearl
    • Bulletin of the Korean Chemical Society
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    • 제9권5호
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    • pp.322-324
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    • 1988
  • Selective reduction of aldoximes and ketoximes with lithium borohydride in tetrahydrofuran was investigated. Thus, aldoximes and cyclic ketoximes such as hexanaldoxime, heptanaldoxime, cyclopentanone oxime and cyclohexanone oxime were reduced smoothly to the corresponding N-monosubstituted hydroxylamines at room temperature in 65-93% yield. The reduction of alicyclic ketoxime was very slow, requiring somewhat high reaction temperature ($65^{\circ}C$) for the complete reduction to give the hydroxnylamines. The reduction of aromatic oximes such as benzaldoxime and acetophenone oxime was very sluggish, giving a mixture of the corresponding hydroxylamines and amines at $65^{\circ}C$.

The Synthesis of Chlorin-based Photosensitizers for using in Photodynamics Therapy by Modification of Methyl Pyropheophorbide-a

  • Wang, Jin-Jun;Han, Guang-Fan;Shim, Young-Key
    • Journal of Photoscience
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    • 제8권2호
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    • pp.75-77
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    • 2001
  • The Grignard reaction of methyl pyropheophorbide-a (MPP-a) was performed to introduce lengthy alkyl chain for improving lipophilicity. After the introduction of alkyl chain to the both of carbonyls, peripheral aldehyde and cyclopentanone, the obtained diol 3 was subjected to dehydration to give monodehydrate product 4 selectively. The Qy band of prepared compounds were affected by the substituents on the Qy axis (N$\sub$21/-N$\sub$23/).

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Cyclohexanol 이용성 세균의 분리 및 특성 (Isolation and Characterization of Cyclohexanol-utilizing Bacteria)

  • 김태강;이인구
    • 한국미생물·생명공학회지
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    • 제27권2호
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    • pp.107-112
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    • 1999
  • A bacterium, which can utilize cyclohexanol as a sole source of carbon and energy, was isolated from sludge in sewage of Ulsan Industrial Complex for Petrochemicals, Korea and identified as Rhodococcus sp. TK6. The growth conditions of the bacteria were investigated in cyclohexanol containing media. The bacteria utilized cyclohexanol, cyclohexanone, cyclohexane-1,2=diol, cyclopentanol, cyclopentanone, and $\varepsilon$-caprolactone but not cyclohexane, cyclohexane-1,2-dione, and cyclooctanone. The bacteria were able to utilize alcohols such as ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-propanol, and 2-butanol as well as cyclohexanol, organic acids such as adipate, propionate, butyrate, valerate, n-caproate, and 6-hydroxycaproate, and aromatic compounds such as phenol, salicylate, p-hydroxbenzoate, and benzoate as a sole source of carbon and energy. Cyclohexanone as a degradation product of cyclohexanol by Rhodococcus sp. TK6 was determined with gas chromatography.

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