Catalytic activity of aqueous cationic polyurethane dispersions: A novel feature of polyurethanes
•Catalytic activity of a polyurethane dispersion was examined for the first time.•CPUD (cationic polyurethane dispersion) was considered as a green catalyst.•CPUD was shown to be an effective and reusable catalyst in the Groebke reaction.•3-Imidazo[1,2-a]pyridines were synthesized under mild conditions by using CPUD catalyst.
Polyurethane ionomers are well-known and user-friendly polymers. Here, we introduce their catalytic activity for organic reactions as a novel aspect of these polymers. We selected an isocyanide-based multicomponent reaction for proving the catalytic activity of polyurethane ionomers. Therefore, a convenient and very mild methodology is described for the preparation of 3-aminoimidazo[1,2-a]pyridines via a three component reaction between 2-aminopyridines, aldehydes and isocyanides in the presence of a cationic polyurethane dispersion at low reaction temperatures, in short reaction times and excellent yields.
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Journal: Applied Catalysis A: General - Volume 468, 5 November 2013, Pages 10–17