Copper Catalysts for Aerobic Oxidation of Alcohols - Transition Metal Catalysis in Aerobic Alcohol Oxidation - page 64

hybrid polymer-inorganic copper nanoparticle-polyacrylamide-mesoporous
silica SBA-15 has been reported to serve as a good recyclable catalyst in the
oxidation of alcohols. 141

d n 4 r 4 n g | 0

2.4 Conclusion
Investigations on copper complexes have helped to improve the chemo-,
regio- and enantioselectivity of catalytic reagents towards the oxidation of
alcohols. Although a number of effective copper-based catalysts for alcohol
oxidations have been developed, finding catalytic systems with high activity
and wide applications needs further effort. The range of substrates needs to
be extended so that they can be oxidized under environmentally friendly
conditions. The design of green catalysts mandatorily excludes any radical
initiator as co-oxidant, and rather includes aerial oxidation reactions in
environmentally friendly solvents. Moreover, to increase catalytic activity,
attention needs to be paid to the recyclability of the catalyst. Hence the use
of polymeric solid supports, nanoporous materials and thermally stable
silica as adsorbents has been initiated for heterogeneous-phase catalytic
reactions. Immobilized catalysts on solid supports can be easily separated
from the reaction medium and offer high selectivity and catalytic yields of
the products and are reusable. Further studies in these directions would
provide useful information for the development of highly ecient copper-
based alcohol oxidation catalysts for practical and industrial applications.

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