Copper on responsive polymer microgels: a recyclable catalyst exhibiting tunable catalytic activityElectronic supplementary information (ESI) available: Experimental procedures, and characterization data. See DOI: 10.1039/c4cc06436d

Copper has been immobilized on a chitosan-based responsive polymer microgel by simply stirring the microgel dispersion with copper sulfate. The ensuing catalyst is highly active for a model azide-alkyne [3+2]-cycloaddition reaction, and can be recycled at least 5 times; the catalytic activity can be tuned via swelling-deswelling transitions of the polymer gels. Copper immobilized on a chitosan-based responsive polymer microgel is highly active for a model azide-alkyne [3+2]-cycloaddition reaction and is recyclable.