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We report herein the design and preparation of novel magneto-polymeric nanohybrids that can be used as efficient and recyclable Pickering interfacial catalyst (PIC) in selective oxidation of alcohols. The nanohybrids Fe 3 O 4 @SiO 2 @PTMA, bearing catalytic TEMPO functionalities, were synthesized through distillation-precipitation polymerization (DPP) of the precursor monomer 2,2,6,6-tetramethyl-4-piperidyl methacrylate (TMPM) and subsequent oxidation reaction. TEM, FT-IR, DLS, EA confirmed and quantified the TEMPO loading of nanohydrids (1.0–2.4 mmol · g −1 ). It was found that the TEMPO loading, particle size, as well as surface hydrophilicity could be finely tuned via simply adjusting the TMPM monomer fraction during polymerization. The performance of the resultant nanohybrids as PIC was then evaluated in a typical Anelli system, which showed superior catalytic activity for selective oxidation of alcohols. Moreover, the PIC can be easily recycled by applying magnetic field, and reused for the following cycles of oxidation without any loss on either conversion or selectivity. [ABSTRACT FROM AUTHOR]

Atom transfer radical polymerization (ATRP) has been considered to be an efficient strategy for constructing functional macromolecules owing to its simple operation and versatile monomers, and thus it is of great significance to develop ideal catalysts with higher activity and perfect reusability. We constructed a peroxidase mimic through the grafting of heme onto metal-organic frameworks UiO-66-NH 2 (ZrMOF), namely Heme-ZrMOF. After the systematic characterization of structure, the composite Heme-ZrMOF was demonstrated to possess high peroxidase activity using 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) and 3,3′,5,5′-tetramethylbenzidine as substrates. The enzyme mimic was then used as catalysts in the ATRP reactions of different monomers, in which favorable monomer conversion (44.6–98.0%) and product molecular weight (8600–25,600 g/mol) could be obtained. Compared to free heme, Heme-ZrMOF could efficiently achieve the easy separation of heme from the catalytic system and facilitate the ATRP reaction in an aqueous environment to avoid the utilization of organic solvents. In conclusion, the enzyme mimic Heme-ZrMOF could be potentially used as an effective catalyst for preparing well-defined polymers with biomedical applications. [ABSTRACT FROM AUTHOR]