Results 81 to 90 of about 2,093,167 (240)

How Lewis Acids Catalyze Diels–Alder Reactions [PDF]

, 2020
The Lewis acid(LA)-catalyzed Diels–Alder reaction between isoprene and methyl acrylate was investigated quantum chemically using a combined density functional theory and coupled-cluster theory approach.
Israel Fernández, Pascal Vermeeren, Bickelhaupt, F.M., Fernández, Israel, Bickelhaupt, Matthias, Bickelhaupt, F. Matthias, Trevor A. Hamlin, Vermeeren, Pascal; id_orcid, Hamlin, Trevor, Fernández López, Israel, Hamlin, Trevor A.; id_orcid, Fernandez, I., F. Matthias Bickelhaupt, Vermeeren, Pascal, Hamlin, Trevor A.   +14 more
core   +1 more source

Estudos sobre o uso do NbCl5 como ácido de Lewis em reações de Povarov

Orbital: The Electronic Journal of Chemistry, 2011
RESUMO: O objetivo deste trabalho foi investigar o uso de NbCl5 como ácido de Lewis em reações de cicloadição (Reação Aza-Diels-Alder (Povarov)) entre bases de Schiff e éteres enólicos.
Luiz Carlos Silva-Filho, Mayara Frenhe
doaj   +1 more source

A mechanistic study of the Diels-Alder reaction of isoprene with some substitutes benzalmalononitriles

, 1980
This work was a kinetic study of the Diels-Alder reaction of isoprene with variously substituted benzalmalononitriles. Application of the Hammett equation, a linear free energy relationship, to the kinetic rate data yielded a value of 1.31 for rho.
Copp, James D.
core  

Taming a Blue Gas—Structure and Chemistry of Hexafluorothioacetone

Angewandte Chemie International Edition, EarlyView.
Hexafluorothioacetone (1), a blue gas at r.t., was synthesized by flash vacuum pyrolysis of its cyclic dimer at 660°C. We discuss fundamental properties of elusive 1, including single‐crystal structure and nuclear magnetic resonance spectroscopy, despite its tendency to dimerize even at –74°C.
Hennes Günther, Antti J. Karttunen, Xiulan Xie, Frank Tambornino   +3 more
wiley   +1 more source

Anthracen- und Anthrachinon-Oligomere mit ortho-Cyclophanverknüpfung durch wiederholte Diels-Alder-Reaktion von 1,2,5,6-Tetra-exo-methylencyclooctan

CHIMIA, 1988
The design of efficient organic electron acceptors requires oligomeric and polymeric hydrocarbons in which separate redox-active units are connected in a sterically variable fashion.
Manfred Wagner, Werner Wohlfarth, Klaus Müllen   +2 more
doaj   +1 more source

Activation of Metal Complexes With Ultrasound Waves for Targeted Anticancer Therapy

Angewandte Chemie International Edition, EarlyView.
Ultrasound enables non‐invasive activation of metal‐based therapeutics deep within tumors. Acoustic cavitation can drive sonodynamic reactive oxygen species generation or mechanochemical metal–ligand bond dissociation, enabling controlled release of bioactive payloads.
Félix Grosjean, Nicolás Montesdeoca, Gilles Berger, Johannes Karges   +3 more
wiley   +1 more source

On the Question of the Course of the Hetero Diels–Alder Reactions Between N-(2,2,2-Trichloroethylidene)Carboxamides and Dicyclohexylcarbodiimide: A New Case of the Stepwise Zwitterionic Cycloaddition Process

Molecules
The regioselectivity and the molecular mechanism of the Diels–Alder reactions between N-(2,2,2-trichloroethylidene)carboxamides and dicyclohexylcarbodiimide were explored based on the ωB97xd/6-311G(d) (PCM) calculations.
Przemysław Woliński, Karolina Zawadzińska-Wrochniak, Ewa Dresler, Radomir Jasiński   +3 more
doaj   +1 more source

Preparation and Reaction Chemistry of Novel Silicon-Substituted 1,3-Dienes

Molecules, 2015
2-Silicon-substituted 1,3-dienes containing non transferrable groups known to promote transmetallation were prepared by Grignard chemistry and enyne metathesis.
Partha P. Choudhury, Mark E. Welker
doaj   +1 more source

Synthesis of 3-Alkenyl-1-azaanthraquinones via Diels-Alder and Electron Transfer Reactions

Molecules, 2002
A convenient route to 3-alkenyl-1-azaanthraquinones via a hetero Diels-Alder reaction between an azadiene and naphthoquinone, a free radical chlorination and an electron transfer reaction is reported.
Patrice Vanelle, Vincent Rémusat, Pascal Rathelot   +2 more
doaj   +1 more source

Diels-Alder reactions of imino dienophiles

, 2016
Kutatómunkám során célul tűztük ki N-toziloxim és N-szulfonil imin származékok előállítását benzaldehid származékokból kiindulva, majd ezen vegyületek aza-Diels-Alder reakcióit kívántam vizsgáltam tetrahidropiridin származékok előállítására. A lehetséges
Auksz, Flóra
core