• Title/Summary/Keyword: 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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    • v.29 no.10
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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.

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

  • Lee, Gab-Yong
    • Journal of the Korean Chemical Society
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    • v.45 no.3
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    • pp.207-212
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    • 2001
  • DFT calculations have been performed on several substituted 1,4-diaza-1,3-butadienes (1,4-DABs) with electron donating and withdrawing groups at the terminal two nitrogens to investigate the reactivity of Diels-Alder reaction with acrolein. The calculated FMO (Frontier Molecular Orbital) energies for the optimized 1,4-disubstituted-1,4-DABs have been used to explain both normal and inverse electron demand Diels-Alder reactions. It is shown that the electron donating and withdrawing substituents lead to the normal(HOMO diene controlled) and inverse electron demand (LUMO diene controlled) Diels-Alder reactions, respectively.

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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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    • v.7 no.3
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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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    • v.15 no.6
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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.