Organocatalytic, regioselective nucleophilic "click" addition of thiols to propiolic acid esters for polymer-polymer coupling

Discerning Tastes : The regioselectivity of the nucleophilic addition of thiols to electron‐deficient alkynes is controlled by the choice of the solvent (i.e. the polarity of the reaction mixture) and the catalyst. Both thioalkenes and dithianes can be prepared in a rapid reaction that generates no by‐products (see scheme). In turn the utility of this reaction is shown for efficient end‐group modification of polymers.