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A magnetically retrievable mixed-valent Fe₃O₄@SiO₂/Pd⁰/Pd^II nanocomposite exhibiting facile tandem Suzuki coupling/transfer hydrogenation reaction.

ABSTRACT: Herein, we report a magnetically retrievable mixed-valent Fe₃O₄@SiO₂/Pd⁰/Pd^IINP (5) nanocomposite system for tandem Suzuki coupling/transfer hydrogenation reaction. The nanocomposite 5 was prepared first by making a layer of [Formula: see text] on [Formula: see text] followed by deposition of [Formula: see text] and sorption of [Formula: see text] ions successively onto the surface of Fe₃O₄@SiO₂NP. The nanocomposite was characterized by powder XRD, electron microscopy (SEM-EDS and TEM-EDS) and XPS spectroscopy techniques. The mixed-valent [Formula: see text] present onto the surface of nanocomposite 5 was confirmed by XPS technique. Interestingly, the mixed-valent nanocomposite Fe₃O₄@SiO₂/Pd⁰/Pd^IINP (5) exhibited tandem Suzuki coupling/transfer hydrogenation reaction during the reaction of aryl bromide with aryl boronic acid (90% of C). The nanocomposite 5 displayed much better reactivity as compared to the monovalent Fe₃O₄@SiO₂/Pd⁰NP (3) (25% of C) and Fe₃O₄@SiO₂/Pd^IINP (4) (15% of C) nanocomposites. Further, because of the presence of magnetic [Formula: see text], the nanocomposite displayed its facile separation from the reaction mixture and reused at least for five catalytic cycles.

SUBMITTER: Singh P

PROVIDER: S-EPMC8085233 | biostudies-literature |

REPOSITORIES: biostudies-literature

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