Advantages of Covalent Immobilization of Metal‐Salophen on Amino‐Functionalized Mesoporous Silica in Terms of Recycling and Catalytic Activity for CO 2 Cycloaddition onto Epoxides

Autor: Anna Proust, Sébastien Beaudoin, Franck Launay, Matthieu Balas, Richard Villanneau
Přispěvatelé: Laboratoire de Réactivité de Surface (LRS), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: European Journal of Inorganic Chemistry
European Journal of Inorganic Chemistry, Wiley-VCH Verlag, 2021, 2021 (16), pp.1581-1591. ⟨10.1002/ejic.202100150⟩
ISSN: 1434-1948
1099-0682
Popis: International audience; NiII and MnIII Schiff base complexes (Salophen-Ni and Salophen-MnCl) bearing a pending carboxylic group were prepared and characterized. Both complexes were grafted onto a mesoporous amino-functionalized SBA-15 silica, by formation of an amide function between the propylamine groups of the support and the carboxylic acid functions of the salophen ligand (corresponding respective to 1.30 wt.% of Ni and 1.06 wt.% of Mn). The co-catalytic behaviour of the free and grafted complexes was then evaluated in the CO2 cycloaddition reaction onto styrene oxide, using tetra-butylammonium bromide (n−Bu4NBr) as the main catalyst. In homogeneous conditions, the MnIII Schiff base complex and the NiII one, to a lesser extent, behave as efficient co-catalysts for this reaction (styrene conversion of 100 % and 65 % respectively after 3 h at 120 °C, under 15 bars of CO2). Upon immobilization at the surface of the amino-functionalized SBA-15, we showed that the co-catalytic activity of the less efficient one, i. e. Ni2+ salophen complex, could be enhanced (reaching a full conversion after 7 h), hence highlighting a potential synergistic effect between the unused amine functions of the support and the Ni2+ salophen co-catalyst. Both salophen complexes were successfully re-used in homogeneous conditions or after their immobilization without any appreciable loss of activity. This work is only a first step towards a completely heterogeneous catalytic system, in which the tetraalkylammonium halide catalyst and the metal-salophen co-catalyst will both be covalently anchored on the same support
Databáze: OpenAIRE