Effect of fluorine or oxygen atom(s) in propargylic position on the reactivity in click chemistry

The use of especially designed ω-diynes allows to establish, through competitive reactions, the effect of C–F, C–OH, CF2, CO and C(OMe)2 substituents on the reactivity of neighbouring triple bonds in click chemistry and this gives not only a reactivity scale but also a direct access to the difference in activation energies between the competitive reaction pathways.