Recoverable silica-gel supported binam-prolinamides as organocatalysts for the enantioselective solvent-free intra- and intermolecular aldol reaction
作者:Abraham Bañón-Caballero、Gabriela Guillena、Carmen Nájera、Enrico Faggi、Rosa María Sebastián、Adelina Vallribera
DOI:10.1016/j.tet.2012.11.097
日期:2013.1
supported binam-derived prolinamides are efficient organocatalysts for the direct intramolecular and intermolecular aldol reaction under solvent-free conditions using conventional magnetic stirring. These organocatalysts in combination with benzoic acid showed similar results to those obtained under similar homogeneous reaction conditions using an organocatalyst of related structure. For the intermolecular process
A remarkable kineticresolution was achieved in a chiral phosphoric acidcatalyzed intramolecular aldol reaction. Its combination with an enantioselective Michael reaction resulted in the formation of cyclohexenone derivatives with excellent enantioselectivities. DFT calculations on the intramolecular aldol reaction revealed the importance of the 3,3′-substituents of the phosphoric acid for the high