Mechanochemistry through Extrusion: Opportunities for Nanomaterials Design and Catalysis in the Continuous Mode

Abstract

The potentialities of mechanochemistry trough extrusion have been investigated for the design of nanosized catalysts and their use in C-C bond-forming reactions. The mechanochemical approach proved successful for the synthesis of supported palladium nanoparticles with mean diameter within 6–10 nm, achieved by the reduction of Pd(II) acetate with ethylene glycol, in the absence of any solvent. A mesoporous N-doped carbon derived from chitin as a renewable biopolymer, was used as a support. Thereafter, the resulting nanomaterials were tested as catalysts to implement a second extrusion based-protocol for the Suzuki-Miyaura cross-coupling reaction of iodobenzene and phenylboronic acid. The conversion and the selectivity of the reaction were 81% and >99%, respectively, with a productivity of the desired derivative, biphenyl, of 41 mmol gcat−1 h−1.

Orthogonal assisted tandem reactions for the upgrading of bio-based aromatic alcohols using chitin derived mono and bimetallic catalysts

“…Even more, the design of solvent free protocols for organic transformations is a thrilling and challenging goal, which has recently spurred the scientific community to explore solventless mechanochemical protocols for the preparation of chemicals and materials. 38–40…”

“…Even more, the design of solvent free protocols for organic transformations is a thrilling and challenging goal, which has recently spurred the scientific community to explore solventless mechanochemical protocols for the preparation of chemicals and materials. [38][39][40] Inspired by such premises, the final stage of this work was dedicated to evaluating the catalytic performance of the synthesized materials, particularly the Mo-N/C systems, through mechanochemically-assisted oxidation reactions. More specifically, a solvent free continuous-flow protocol was developed using a twin-screw mini extruder to produce vanillin by the selective oxidation of vanillyl alcohol.…”