Polyimide-supported Cu/2,2,6,6-tetramethyl-1-piperidine-N-oxyl catalytic systems: Aromatic donor-acceptor interaction-directed cooperative catalysis

Cooperative catalysis of Cu/2,2,6,6-tetramethyl-1-piperidine-N-oxyl nanocatalysts supported by ultraviolet light-responsive polyimides

“…In consistence with previous results, 36 nanocatalysts possessed randomly distributed aromatic stacking clusters (Fig. 2A and S15 †).…”

“…A Significant loss in activity was found while reusing the catalysts (Fig. S17†), 34–36 likely caused by degradation of intermediates derived from TEMPO. 38…”

“…To increase local concentrations of functional groups within nanocatalysts, aromatic stacking interactions were used for the construction of polymer-supported nanocatalysts. 35,36 NDI-based polyimides were used as supports for the immobilization of pyrenecontaining catalytic components via nanoprecipitation. 36 Although nanocatalysts with improved catalytic properties were prepared by using hydrophobic interactions and aromatic stacking interactions, more efforts are required to gain more insights into structure-activity relationships and develop strategies that can regulate cooperative behaviours.…”

“…A Significant loss in activity was found while reusing the catalysts (Fig. S17 †), [34][35][36] likely caused by degradation of intermediates derived from TEMPO. 38 To get clearer comparisons of TOF changes with UV light irradiation, ratios of the TOFs without and with UV light irradiation were calculated (TOF 365nm /TOF Dark , Fig.…”

Engineering of polystyrene-supported acid–base catalysts for aldol condensation in water

“…By altering the proximity effect, catalytic performance shall be regulated by tuning the local concentrations of functional groups. [26][27][28][29] The aldol reaction of 4nitrobenzaldehyde (4NBA) with acetone is chosen as a model reaction to evaluate these catalysts. The effect of polymer composition and effective constituent ratio on catalytic performance were examined.…”