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Químio-, régio- e estereosseletividades das reações de Diels-Alder de para-benzoquinonas: um estudo teórico
(Universidade Federal de São CarlosBRUFSCarPrograma de Pós-Graduação em Química - PPGQ, 2014-07-23)
In this work, some computational theoretical studies on the reactivity of para-benzoquinones and their derivatives in Diels-Alder reactions were proposed These studies were done in order to compliment the corresponding ...
Understanding the influence of Lewis acids in the regioselectivity of the Diels–Alder reactions of 2-methoxy-5-methyl-1,4-benzoquinone: A DFT study
(Elsevier B.V., 2009-03-03)
The mechanisms of the Diels–Alder (DA) reactions of 2-methoxy-5-methyl-1,4-benzoquinone 1 with 2-
methyl-1,3-butadiene 2, in the absence and in the presence of LA catalysts, have been studied using the
DFT method at the ...
Understanding the stereo- and regioselectivities of the polar Diels-Alder reactions between 2-acetyl-1,4-benzoquinone and methyl substituted 1,3-butadienes: a DFT study
(JOHN WILEY & SONS LTD, 2009-06)
The polar Diels-Alder (DA) reactions of 2-acetyl-1,4-benzoquinone (acBQ) with methyl substituted 1,3-butadienes have been studied using DFT methods at the B3LYP/6-31 G(d) level of theory. These reactions are characterized ...
Understanding the influence of Lewis acids in the regioselectivity of the Diels-Alder reactions of 2-methoxy-5-methyl-1,4-benzoquinone: A DFT study
(2009)
The mechanisms of the Diels-Alder (DA) reactions of 2-methoxy-5-methyl-1,4-benzoquinone 1 with 2-methyl-1,3-butadiene 2, in the absence and in the presence of LA catalysts, have been studied using the DFT method at the ...
Understanding reactivity and regioselectivity in Diels–Alder reactions of a sugar-derived dienophile bearing two competing EWGs. An experimental and computational study
(Elsevier, 2015-08)
The effect of an extra EWG in the reactivity and regioselectivity in Diels?Alder reactions of β-cyanolevoglucosenone and 4 different dienes was studied by a joint computational and experimental study. Conceptual DFT analysis ...
Polar Diels-Alder Reactions using Heterocycles as Electrophiles. Influence of Microwave Irradiation
(ScienceDomain international, 2015-06)
In this work we studied a series of polar Diels-Alder reactions using different heterocycles derivatives acting as electrophiles joint to dienes of different nucleophilicity, analyzing the effect of the microwave irradiation ...
Studies on chemo- and diastereo-selectivity of the Diels-Alder reactions of sulfinyltoluquinones with cyclopentadiene
(NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS, 2009)
Sulfinyltoluquinones (2a-2c) were submitted to thermal or catalyzed [4+2] cycloaddition reactions with cyclopentadiene. For p-tolylsulfinyltoluquinones (2b) and (2c), almost complete C2-C3-chemo- and unlike-diastereoselectivity ...
Regioselectivity in the Diels-Alder reaction of 8,8- dimethylnaphthalene-1,4,5(8H)-trione with 2,4-hexadien-1-ol
(Elsevier Ltd, 1999)
The Diels-Alder reactions of 8,8-dimethylnaphtalene-1,4,5(8H)-trione with 2,4-hexadien-1-ol and its O-acetyl derivative were investigated in different solvents. The regiochemistry of the cycloaddition of the hexadienol was ...
Looking at the big picture in activation strain model/energy decomposition analysis: The case of the: Ortho - Para regioselectivity rule in Diels-Alder reactions
(Royal Society of Chemistry, 2020-02)
The regioselectivity of the Diels-Alder reaction is predicted by the ortho-para rule which has been explained from FMO theory. Using DFT calculations, the activation-strain model and energy decomposition analysis we studied ...
Alkylhalovinylboranes: a new class of Diels-Alder dienophiles
(Royal Society of Chemistry, 2018-10)
The Diels-Alder reactions of alkylhalovinylboranes have been investigated theoretically and experimentally. Alkylhalovinylboranes presented higher reactivity than the corresponding dialkylvinylboranes. Although endo/exo ...