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1

A mechanism study and an investigation of the reason for the stereoselectivity in the [4+2] cycloaddition reaction between cyclopentadiene and gem-substituted ethylene electrophiles

Aitouna Abdelhak Ouled, Barhoumi Ali, Zeroual Abdellah

Scientiae Radices

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2023

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Vol. 2, Iss. 3

217--228

EN

The Molecular Electron Density Theory is applied to the [4+2] cycloaddition reaction between cyclopentadiene and gem-substituted ethylene electrophiles. Calculations are made for reactions, activation energies, and reactivity indices. The results of the experiment are perfectly consistent with activation energies, which unequivocally show that this cyclization’s are is highly stereoselective, in addition, based on ELF examination, the mechanism of these [4+2] cycloadditions occurs in two phases, The mechanisms of these reactions demonstrate that the term "pericyclic reaction" is no more relevant in the 21st century and has been replaced by the term "pseudocyclic".

2

Bio-Potent (5-chloro-2-thienyl)-3-(substituted Phenyl) bicyclo[2.2.1]heptane-2-yl Methanone Derivatives

Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 42

1--12

EN

A series of (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones have been synthesized by fly-ash catalyzed [4+2] cycloaddition Diels-Alder reaction of cyclopentadiene and 5-chloro-2-thienyl chalcones under cooling conditions. The yields of the methanones are more than 60%. The synthesized (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones are characterized by their physical constants and spectral data. The antimicrobial, antioxidant and insect antifeedant activities of synthesized methanones have been studied using their respective bacterial, fungal strains, DPPH radical scavenging activity and Dethler’s leaf-discs bioassay method.

3

Sprzężone nitroalkeny w reakcjach [2+4] cykloaddycji z cyklopentadienem

Kwiatkowska M., Jasiński R., Barański A.

Czasopismo Techniczne. Chemia

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2006

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R. 103, z. 4-Ch

95-104

PL

W niniejszym artykule przeprowadzono krytyczną analizę dostępnych danych literaturowych dotyczących stereoselektywności reakcji [2+4] cykloaddycji sprzężonych nitroalkenów z cyklopentadienem oraz reaktywności nitroalkenów jako filodienów.

EN

The work is the critical review of available literature data that are concerted with stereoselectivity of [2+4] cycloadditions reactions of conjugated nitroalkenes with cyclopentadiene. The reactivity of nitroalkenes was also studied.

4

Reakcje [2+4] cykloaddycji cyklopentadienu i furanu z wybranymi β-nitrostyrenami w świetle obliczeń PM3 i PM3/COSMO

Bujak M., Barański A.

Czasopismo Techniczne. Chemia

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2004

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R. 101, z. 1-Ch

13-29

PL

Niniejsza praca dotyczy kwantowochemicznych studiów nad reakcją [2+4] cykloaddycji wybranych β-nitrostyrenów z cyklopentadienem i furanem. Obliczenia prowadzono za pomocą metody PM3 i PM3/COSMO dla fazy gazowej oraz symulowanej obecności medium dielektrycznego.

EN

The PM3 and PM3/COSMO calculations for [2+4] cycloaddition reactions of some β-nitrostyrenes to cyclopentadiene and furane were carried out. Calculations were performed for the gas phase and for dielectric continuum with ε = 2,4 and 37,8.

5

Diastereoselective [4+2} Cycloaddition of Cyclopentadiene to N-Tosyliminoacetyl Derivatives of Chiral Secondary Alcohols

Szymański S., Marzec M., Jurczak J.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 6

831-837

EN

Syntheses of five N-tosylimines of chiral glyoxylates are described. The N-tosylimines obtained were used as dienophiles in the Lewis acid-catalyzed asymmetric hetero- -Diels-Alder reaction with cyclopentadiene to afford cycloadducts with moderate diastereoisomeric excess.