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Cycloisomerization of Conjugated Trienones and Isomeric 2 H -Pyrans: Unified Strategy toward Cyclopenta[ b ]furans
(American Chemical Society, 2015-06)
Conjugated trienones and isomeric 2H-pyrans were found to engage in a novel cycloisomerization cascade toward cyclopenta[b]furan derivatives. Knoevenagel chemistry and pericyclic reactions meet again to expand the ...
The iso-Nazarov reaction
(Royal Society of Chemistry, 2017-11)
The construction of five-membered rings is essential in organic chemistry. In this context, pentannulation reactions that provide a straightforward access to cyclopentenones are of particular interest, as these structures ...
An Interrupted Vinylogous Iso-Nazarov Reaction: Cycloisomerization of Conjugated Trienones to Cyclopenta[b]furan Derivatives
(American Chemical Society, 2014-05)
Iron(III) chloride-catalyzed cyclopentannulation of π-conjugated 1,3-dicarbonyl compounds is described. An interrupted vinylogous iso-Nazarov reaction of trienones was established in which cyclopenta[b]furan derivatives ...
Gold-Catalyzed Cycloisomerization of Alkyne-Containing Amino Acids: Controlled Tuning of C–N vs. C–O Reactivity
(Wiley VCH Verlag, 2016-06)
Versatile alkyne-containing amino acids were used as ambident precursors in the divergent synthesis of alkylidenelactones and 1-pyrrolines. Two gold-catalyzed protocols were applied for selective intramolecular O- and ...
Biomimetic Domino Knoevenagel/Cycloisomerization Strategy for the Synthesis of Citridone A and Derivatives
(American Chemical Society, 2021-09)
Studies on Knoevenagel condensations between conjugated dienals and 4-hydroxy-2-pyridone/quinolone-type 1,3-dicarbonyl equivalents led to the development of a simple one-pot strategy to access citridone A and related ...
"Enaminonas: síntese e aplicação em reações de cicloisomerização e de acoplamento"
(Universidade Federal de Santa MariaBRQuímicaUFSMPrograma de Pós-Graduação em Química, 2009-08-12)
This work describes the synthesis of a series of twenty 4-[alkyl (aryl) (2-propinyl amino)-3-alken-2-ones], [R2C(O)CH=C(R1)N(R)(CH2C≡CH), where R2 = CF3, CCl3, CO2Et; R1 = Me, Et, Pr e R= Pr, Ph, Bn, 4-MeC6H4] obtained ...
Synthesis of a Small Library of Imidazolidin-2-ones using Gold Catalysis on Solid Phase
(American Chemical Society, 2016-08)
An efficient and high-yielding solid phase synthesis of a small library of imidazolidin-2-ones and imidazol-2-ones was carried out employing a high chemo- and regioselective gold-catalyzed cycloisomerization as a key step. ...
Síntese de furanos trissubstituídos via reações de oxopaladação aeróbica
(Universidade Federal de São CarlosUFSCarPrograma de Pós-Graduação em Química - PPGQCâmpus São Carlos, 2019-02-25)
Furans are important heterocyclics with broad application in synthesis as a building block, frequently presented in a wide range of compounds that exhibit biological activity, including natural products. Intramolecular ...
Iodine-Catalyzed Iso-Nazarov Cyclization of Conjugated Dienals for the Synthesis of 2-Cyclopentenones
(American Chemical Society, 2018-11)
Molecular iodine was identified as an efficient catalyst for the cycloisomerization of conjugated dienals to substituted 2-cyclopentenones. DFT calculations suggested an unexpected concerted character for this cyclization.
Multicomponent Domino Synthesis of Cyclopenta[ b]furan-2-ones
(American Chemical Society, 2018-07)
A stereoselective multicomponent reaction involving Meldrum's acid, a conjugated dienal, and an alcohol is reported. Valuable cyclopenta[b]furan-2-ones are obtained as products of this straightforward transformation, which ...