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Chiral Lewis acid catalysts in diels-Alder cycloadditions: mechanistic aspects and synthetic applications of recent systems
(Sociedade Brasileira de Química, 1997)
Design and synthesis of angucyclinone 5-aza analogues
(GEORG THIEME VERLAG KG, 2006)
A highly efficient one-pot procedure for the synthesis of phenanthridine-1,7,10-triones from acylbenzoquinones and cyclic enaminones is reported. The cycloaddition reactions of these quinones with 1-trimethylsilyloxybutadiene ...
Regioselectivity in the Diels-Alder reaction of 8,8-dimethylnaphthalene-1,4,5(8H)-trione with 2,4-hexadien-1-ol
(PERGAMON-ELSEVIER SCIENCE LTD, 1999-01-15)
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 ...
Five-Membered aromatic heterocycles in diels-alder cycloaddition reactions: Theoretical Studies as a Complement of the Experimental Researches
(Bentham Science Publishers, 2011-02)
The dienophilic behavior of electron-deficient substituted five-membered aromatic heterocyclices in polar cycloaddition reactions is studied from a theoretical point of view employing the global electrophilicity index to ...
A chiral auxiliary derived from levoglucosenone in assymetric Diels-Alder transformations
(Pergamon-Elsevier Science Ltd, 2005-10-10)
The Diels-Alder reaction of the acrylate derived from levoglucosenone with cyclopentadiene was studied under several conditions, in the presence and absence of a Lewis acid. The results showed satisfactory diastereomeric ...
Comprehensive DFT study on site-, regio-, and stereoselectivity of diels-alder reactions leading to 5-hydroxybenzofurans
(Wiley VCH Verlag, 2011-02)
Diels-Alder reactions between the substituted furans 1a-1c and Danishefsky's diene (2), yielding 5-hydroxybenzofurans, were studied by density functional theory [B3LYP/6-31G(d) level] in benzene as solvent (SP/CPCM). The ...
Allenylboronic acid pinacol ester: a selective partner for [4 + 2] cycloadditions
(American Chemical Society, 2021-07)
We have studied the reaction of allenylboronic acid pinacol ester with cyclopentadiene with experimental and computational methods. The reaction occurred efficiently with complete Diels-Alder periselectivity and regioselectivity ...
Gas-phase polar [4(+)+2] cycloaddition with ethyl vinyl ether: a structurally diagnostic ion-molecule reaction for 2-azabutadienyl cations
(John Wiley & Sons LtdChichesterInglaterra, 2003)