Low-generation fluorescent polyurethane dendrimers via late-stage modification using azide-alkyne click chemistry

Protecting group free one-pot multicomponent Curtius reaction afforded a versatile MN2 type dendron, ensuring late-stage modification of both dendron and dendrimer to afford highly fluorescent symmetrical and unsymmetrical (Janus) polyurethane dendrimers. Fluorescence study of these dendrimers exhibited the Forster resonance energy transfer (FRET) between blue and mint green fluorophores.