2024-03-28T09:43:29Zhttps://uvadoc.uva.es/oai/requestoai:uvadoc.uva.es:10324/323702021-06-24T07:42:36Zcom_10324_1187com_10324_931com_10324_894com_10324_28542com_10324_952col_10324_1408col_10324_28543
Chiral Bifunctional Thioureas and Squaramides and Their Copolymers as Recoverable Organocatalysts. Stereoselective Synthesis of 2-Substituted 4-Amino-3-nitrobenzopyrans and 3-Functionalized 3,4-Diamino-4H-Chromenes
Andrés García, José María
Maestro Fernández, Alicia
Valle Álvarez, María
Pedrosa Sáez, Rafael
Aminobenzopiranos
Aminobenzopyranes
Producción Científica
Novel styryl-substituted thioureas and squaramides were obtained in three steps from commercially available 4-hydroxy-3,5-dichloroaniline. These organocatalysts promote cascade reactions in high yields and excellent stereoselection. By using only a 5 mol % loading of catalyst, it is possible to obtain 2,3,4-trisubstituted benzopyrans by reaction of α-amido sulfones derived from salicyladehydes and nitrostyrenes or 2,3,4-trisubstituted 4H-chromenes by reaction of the same α-amido sulfones with (phenylsulfonyl)acetonitrile in excellent diastereo- and enantioselectivities. Two polymeric thioureas and squaramides were prepared by copolymerization of the best monomeric catalysts with styrene and divinylbenzene and used for the same transformations. These polymers behave also as excellent stereoselective catalysts that can be recovered and reused for five cycles.
2019-11-11
2019-11-11
Ministerio de Economía, Industria y Competitividad (Project FEDER-CTQ2014-59870-P)
Junta de Castilla y León (programa de apoyo a proyectos de investigación - Project FEDER-VA115P17)
2018-10-29T13:49:37Z
2018
info:eu-repo/semantics/article
Journal of Organic Chemistry, 2018, 83 (10), pp 5546–5557
0022-3263
http://uvadoc.uva.es/handle/10324/32370
https://doi.org/10.1021/acs.joc.8b00567
eng
https://pubs.acs.org/doi/10.1021/acs.joc.8b00567
Attribution-NonCommercial-NoDerivatives 4.0 International
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
application/pdf
American Chemical Society
https://uvadoc.uva.es/bitstream/10324/32370/6/Chiral-Bifunctional-Thioureas-Postprint.pdf.jpg
Hispana
TEXT
http://creativecommons.org/licenses/by-nc-nd/4.0/
UVaDOC. Repositorio Documental de la Universidad de Valladolid
http://uvadoc.uva.es/handle/10324/32370