• 제목/요약/키워드: Diels-Alder reaction

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Study of Solvent Effects in Diels-Alder Reaction through Charge Transfer Formation by Using Semi-empirical Calculations

  • Shihab, Mehdi Salih
    • Bulletin of the Korean Chemical Society
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    • 제29권10호
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    • pp.1898-1904
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    • 2008
  • Study of computational model of the concerted Diels-Alder reaction between 9,10-dimethyl anthracene (as donor) and tetracyanoethylene (as acceptor) in absence and in presence of aromatic solvents (benzene, mesitylene and hexamethylbenzene, as donors) using an AM1 semi-empirical method. AM1 method used to study the neutral charge transfer complex models that could be expected between donor and acceptor during the course of the concerted Diels-Alder reaction. Calculated enthalpies of reaction of the charge transfer complexes models showed physical and chemical meaning for explain the effect of aromatic solvents on the kinetic process of concerted Diels-Alder reaction that contains tetracyanoethylene.

1,4-Diaza-1,3-butadiene류의 Diels-Alder반응에 미치는 치환기 효과에 대한 DFT연구 (DFT Studies for the Substituent Effect on the Diels-Alder Reaction of 1,4-Diaza-1,3-butadiene)

  • 이갑용
    • 대한화학회지
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    • 제45권3호
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    • pp.207-212
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    • 2001
  • 1.4-Diaza-1,3-butadiene(1,4-DAB)과 acrolein 과의 Diels-Alder 반응의 반응성을 조사하기 위해 1,4-DAB의 말단 두 질소에 전자를 끌거나 주는 기들을 치환시킨 여러 치환 1,4-DAB들에 대해 DFT계산을 수행하였다. 최적화된 구조들에 대해 계산된 FMO(Frontier Mole cular Orbital) 에너지로서 상대적인 반응성을 설명할 수 있었다. 즉, 전자를 주는 기가 치환될 경우에는 normal electron demand 반응이 유리하며, 전자를 끄는 기가 치환될 경우에는 inverse electron demand 반응 메카니즘으로 진행됨을 알 수 있었다.

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Synthesis of a Conformationally-rigid Etorphine Analogous

  • Kim, Keun-Jae;Hahn, Soon-Jong;Lyu, Hark-Soo
    • Bulletin of the Korean Chemical Society
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    • 제7권3호
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    • pp.166-169
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    • 1986
  • In order to synthesize conformationally rigid etorphine analogues having potentially interesting pharmacological activities, synthesis of compound 3 by the reaction of compound 4 and compound 5 via intramolecular Diels-Alder reaction has been attempted. However, the reaction did not go well and the compound 3 would not be isolated. Therefore, intermolecular Diels-Alder reaction using dimethyl acetylene dicarboxylate was attempted. As shown in scheme 2, Diels-Alder adduct 9 was converted into the target molecule 14 containing the new [2.2.2] bicyclo octane ring in good yields.

The Synthetic Utilization of 2-Hydroxymethyl-2,5-dihydrothiophene 1,1-Dioxide in the Intramolecular Diels-Alder Reaction

  • Lee, Hyo Won;Lee Woong Bae;Choi Lee Ihl-Young
    • Bulletin of the Korean Chemical Society
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    • 제15권6호
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    • pp.448-452
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    • 1994
  • 2-Hydroxymethyl-2,5-dihydrothiophene 1,1-dioxide (1) was prepared from thiophene-2-carboxylic acid by consecutive reactions involving the Birch reduction, esterification, reduction with lithium aluminum hydride, and oxidation with Oxone$^{\circledR}$. The esterification of alcohol 1 with various unsaturated carboxylic acids provided the precursors 8 for the intramolecular Diels-Alder reaction. The cheletropic expulsion of sulfur dioxide from the esters 8 followed by intramolecular Diels-Alder reaction furnished bicyclic ${\gamma}$-and ${\delta}$-lactones.