Adsorption of a Chiral Amine on Alginate Gel Beads and Evaluation of its Efficiency as Heterogeneous Enantioselective Catalyst

Autor: Aguilera, Daniel Antonio, Spinozzi Di Sante, Lisa, Pettignano, Asja, Riccioli, Riccardo, Roeske, Joël, Albergati, Luce, Corti, Vasco, Fochi, Mariafrancesca, Bernardi, Luca, Quignard, Françoise, Tanchoux, Nathalie
Přispěvatelé: Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Haute École d'ingénierie et d'architecture [Fribourg] (HEIA-FR), Department of Organic Chemistry ‘‘A. Mangini', This work was co‐funded through a SINCHEM Grant. SINCHEM is a Joint Doctorate programme selected under the Erasmus Mundus Action 1 Programme (FPA 2013‐037). We thank Prof. Ennio Vanoli and Prof. Roger Marti (Haute Ecole d'Ingénierie et d'Architecture, Fribourg, CH) for stimulating discussions.
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: European Journal of Organic Chemistry
European Journal of Organic Chemistry, Wiley-VCH Verlag, 2019, 2019 (24), pp.3842-3849. ⟨10.1002/ejoc.201900247⟩
ISSN: 1434-193X
1099-0690
Popis: International audience; An organic catalyst derived from quinine can be adsorbed on alginate gels by following a simple protocol. The resulting solvogel beads are competent and highly stereoselective catalysts for an asymmetric Michael reaction.A representative Lewis base organic catalyst (9‐amino‐9‐deoxy epi‐quinine, QNA) can be adsorbed in high yields onto acidic alginate gels (AGs) using a very simple and straightforward protocol. The resulting solvogel beads (QNA@AGs) are active as heterogeneous catalysts in the addition of aldehydes to nitroalkenes, affording the corresponding adducts in good yields and moderate to excellent diastereo‐ and enantio‐selectivities. In these reactions, the carboxylic functions of the biopolymer act as both acidic co‐catalyst and non‐covalent anchoring site for the tertiary amine catalyst (as observed by IR spectroscopy). Use of heterocationic gels, derived from alkaline earth metal gels by proton exchange, provided materials with better mechanical properties and higher porosities, ultimately resulting in higher catalytic activities. This work represents the first utilization of alginates, abundant and renewable biopolymers, as gel supports/media for asymmetric organocatalytic processes.
Databáze: OpenAIRE
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