RT info:eu-repo/semantics/article T1 Supported and Unsupported Chiral Squaramides as Organocatalysts for Stereoselective Michael Additions: Synthesis of Enantiopure Chromenes and Spirochromanes A1 Andrés García, José María A1 Losada, Jorge A1 Maestro Fernández, Alicia A1 Rodríguez Ferrer, Patricia A1 Pedrosa Sáez, Rafael K1 Catálisis K1 Química orgánica AB Novel supported chiral bifunctional squaramides have been easily prepared starting from diamines derived from natural amino acids and commercially available aminoalkyl polystyrene resins. These squaramides behave as excellent stereoselective recoverable organocatalysts in different Michael additions, in neat conditions at room temperature. The reaction on 2-(2-nitrovinyl) phenol as electrophile lead, in excellent yields and enantioselectivities, to intermediates that can be easily transformed into 4H-chromenes, and spirochromanones. PB American Chemical Society SN 0022-3263 YR 2017 FD 2017 LK http://uvadoc.uva.es/handle/10324/28950 UL http://uvadoc.uva.es/handle/10324/28950 LA eng NO Journal of Organic Chemistry, 2017, Volume 82, Issue16, Pages 8444-8454 NO Producción Científica DS UVaDOC RD 24-nov-2024