Thermally Reversible Dendronized Step-Polymers Based on Sequential Huisgen 1,3-Dipolar Cycloaddition and Diels-Alder ``Click'' Reactions

Thermally labile dendronized AA−BB step polymers are described. First through third generation dendritic bisfuran monomers 6a−6c were prepared in part by the Cu(I)-catalyzed azide−alkyne Huisgen 1,3-dipolar cycloaddition reaction and in turn polymerized by the reversible furan−maleimide Diels−Alder reaction. The Diels−Alder reaction conditions were optimized through end-capping studies with N-phenylmaleimide (7). Dendronized step polymers 10a−10c were then formed from reaction with bismaleimide 9 and their assembly, disassembly, and reassembly behavior studied by GPC.