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Theoretical investigation of the Diels-Alder reactions of unsaturated boronates
(Royal Society of Chemistry, 2013-04)
The Diels-Alder reactions of simple unsaturated boronates have been investigated using computational methods and the results were compared with those for the analogue dihalo- and dialkylboranes. Our results indicate that ...
Studies on quinones. Part 32. Regioselective synthesis of benz[b]phenantridines related to phenantroviridone
(PERGAMON-ELSEVIER SCIENCE LTD, 1999)
The Diels-Alder reaction of juglone (4) and bromojuglone 18 with 1-cyclohesenecarbosaldehyde dimethylhydrazone (3) is described. Through these cycloaddition reactions 8-hydroxy-1,2,3,4-tetrahydrobenz[b]phenantridin-7,12-dione ...
A facile microwave-assisted Diels-Alder reaction of vinylboronates
(Royal Society of Chemistry, 2010-11)
The Diels-Alder reaction of vinylboronates can be easily performed using microwave irradiation giving excellent yields of the cycloadducts. Pinacol vinylboronate was the reagent of choice due to its stability towards ...
Estudos sobre o uso de NbCl5 como ácido de Lewis em reações de Povarov
(2011)
The aim of this work was to investigate the use of NbCl5 as Lewis acid in cycloadittion reactions [Reaction Aza-Diels-Alder (Povarov)] between Schiff bases and enol ethers. Comparison of reaction yields, obtained products ...
Stereoselective synthesis of novel diels-alder adducts of p-substituted Methyl Thiocinnamates and Cyclopentadiene
(TAYLOR & FRANCIS INCPHILADELPHIA, 2012)
This article describes the Diels-Alder reaction between methyl thiocinnamates, substituted at the para position by electron-donating and electron-withdrawing groups, with cyclopentadiene in the presence of catechol boron ...
A regioquímica das reações de Diels-Alder de N-tosil para-benzoquinona iminas
(Universidade Federal de São CarlosBRUFSCarPrograma de Pós-Graduação em Química - PPGQ, 2012-02-29)
In this work it was done a comparative study on the reactivity of a variety of dienophiles including para-benzoquinones, their mono-oximes, their N-tosyl mono-oximes and their N-tosylimines on the Diels-Alder reactions ...
SYNTHESIS AND RETRO AZA DIELS-ALDER REACTION OF SOME NEW ISOQUINUCLIDINE DERIVATIVES
(PERGAMON-ELSEVIER SCIENCE LTD, 2009)
N-Benzyl- and N-(alpha-methoxycarbonylethyl)-2,4,6-triphenyl-1,2-dihydropyridines were submitted to Diels-Alder reactions with maleic anhydride or N-phenylmaleimide yielding, diastereoselectively, the corresponding endo-anti ...
Unraveling polar Diels-Alder reactions with conceptual DFT analysis and the distortion/interaction model
(Royal Society of Chemistry, 2014-01)
The reaction energetics of 280 polar Diels–Alder (DA) reactions between 70 dienophiles and 4 dienes have been studied in detail using the B3LYP/6-31G* level of theory, combining conceptual density functional theory (DFT) ...
Bicyclic allyltin derivatives through selective "one pot" hydrostannation - Diels-Alder reaction
(Arkat, 2011-02)
In this paper we report a simple "one pot" procedure to functionalized allyltin derivatives from 1- ethynylcyclohexene. Radical addition of trineophyltin hydride gives quantitatively to (Z,E)-1-(2- trineophylstannylvinyl ...