Hetero type III-B rotaxane dendrimers

Type III-B rotaxane dendrimer is a member of the rotaxane dendrimer family, but it is defined as dendritic polyrotaxane, branched through rings. Such rotaxane dendrimers have been synthesized through versatile copper-catalyzed azide-alkyne cycloaddition reactions. In order to incorporate more functionalities into type III-B rotaxane dendrimers, three different potential functionalities—azobenzene toward light switch, daisy chain toward higher degree of contraction, and extension and cyclobis (paraquat-p-phenylene) (CBPQT) toward redox chemistry—were combined into the original design of type III-B rotaxane dendrimers. Two azo-based G1/G2 and four new G1 and G2 hetero type III-B rotaxane dendrimers were synthesized and characterized by ¹H NMR spectroscopy and electrospray ionization mass spectrometry.