title: Polystyrene or Magnetic Nanoparticles as Support in Enantioselective Organocatalysis? A Case Study in Friedel-Crafts Chemistry.
abstract: Heterogenized versions of the second-generation MacMillan imidazolidin-4-one are described for the first time. This versatile organocatalyst has been supported on 1% DVB Merrifield resin and Fe3O4 magnetic nanoparticles through a copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. The resulting catalytic materials have been successfully applied to the asymmetric Friedel-Crafts alkylation of indoles with α,β-unsaturated aldehydes. While both catalytic systems can be easily recovered and admit repeated recycling, the polystyrene-based catalyst shows higher stability and provides better stereoselectivities.
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science of Technology , Avda. Països Catalans, 16, 43007 Tarragona, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Ranjbar
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science of Technology , Avda. Països Catalans, 16, 43007 Tarragona, Spain.
authors.forename: Paola
authors.initials: P
authors.lastname: Riente
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science of Technology , Avda. Països Catalans, 16, 43007 Tarragona, Spain.
authors.forename: Carles
authors.initials: C
authors.lastname: Rodríguez-Escrich
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science of Technology , Avda. Països Catalans, 16, 43007 Tarragona, Spain.
authors.forename: Jagjit
authors.initials: J
authors.lastname: Yadav
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science of Technology , Avda. Països Catalans, 16, 43007 Tarragona, Spain.
authors.forename: Kishore
authors.initials: K
authors.lastname: Ramineni
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science of Technology , Avda. Països Catalans, 16, 43007 Tarragona, Spain.|Department de Química Orgànica, Universitat de Barcelona , 08080 Barcelona, Spain.
authors.forename: Miquel A
authors.initials: MA
authors.lastname: Pericàs