1,3-Dipolar Cycloaddition for the Creation of Conjugated Polymers Uwe Bunz, School of Chemistry and Biochemistry, Georgia Institute of Technology The pyridine-bearing 1,3-dipolar cycloadduct 3 displays a turn-on fluorescence upon addition of barium, manganese and copper salts. A similar fluorescence turn-on effect is visible when 3 is titrated with trifluoroacetic acid. It is surprising and interesting that these simple triazoles show such an attractive sensory response to divalent metal cations. Synthesis of triazole-containing 1,3-dipolar cycloadducts via copper catalysis Fluorescence response of the adduct 3 upon addition of different metal salts in dichloromethane