Fe3O4-lignin@Pd-NPs: A highly active, stable and broad-spectrum nanocomposite for water treatment.

In this work, we report an environmentally friendly renewable nanocomposite magnetic lignin-based palladium nanoparticles (Fe3O4-lignin@Pd-NPs) for efficient wastewater treatment by decorating palladium nanoparticles without using any toxic reducing agents on the magnetic lignin abstracted from Poplar. The structure of composite Fe3O4-lignin@Pd-NPs was unambiguously confirmed by XRD, SEM, TEM, EDS, FTIR, and Zeta potential. After systematic evaluation of the use and efficiency of the composite to remove toxic organic dyes in wastewater, some promising results were observed as follows: Fe3O4-lignin@Pd-NPs exhibits highly active and efficient performance in the removal of toxic methylene blue (MB) (up to 99.8 %) wastewater in 2 min at different concentrations of MB and different pH values. Moreover, except for toxic MB, the other organic dyes including Rhodamine B (RhB), Rhodamine 6G (Rh6G), and Methyl Orange (MO) can also be removed efficiently by the composite. Finally, the easily recovered composite Fe3O4-lignin@Pd-NPs exhibits well stability and reusability, and catalytic efficiency is maintained well after ten cycles. In conclusion, the lignin-based magnetism Pd composite exhibits powerful potential practical application in industrial wastewater treatment.

Unexpected Cascade Dehydrogenation Triggered by Pd/Cu-Catalyzed C(sp3)-H Arylation/Intramolecular C-N Coupling of Amides: Facile Access to 1,2-Dihydroquinolines.

In this work, we successfully explored an unexpected dehydrogenation triggered by Pd/Cu-catalyzed C(sp3)-H arylation and intramolecular C-N coupling of amides to synthesize the bioactive 1,2-dihydroquinoline scaffold with good regioselectivity and good compatibility of functional groups. This strategy provides an alternative route to realize molecular complexity and diversity from simple and readily available molecules via multiple C-H bond activation. Preliminary mechanistic studies demonstrated that ß,γ-dehydrogenation is triggered by the arylation of the C(sp3)-H bond and the intramolecular C-N coupling.