Selenium containing macrocycles: transformation between Se-N/Se-S/Se-Se bonds

Macrocycles possess potential applications in supramolecular chemistry and biosystems. Thus development of new kinds of macrocycles is of significance. Herein, novel macrocycles containing Se-Se/Se-S bonds were synthesized via transformation between selenium related dynamic covalent bonds. A monomer containing two ebselen moieties was synthesized (M1). The Se-N bonds in M1 were reduced by dithiothreitol, forming Se-S linked dimer (D1). To realize the transformation from Se-S bonds to Se-Se bonds, guest molecules were added as template, triggering the formation of Se-Se linked dimer (D2). The formation of these two new kinds of macrocycles was determined by H-1 NMR and Se-77 NMR, and the necessity of guest molecules was also confirmed. The introduction of ebselen moieties and Se-S bonds or Se-Se bonds into macrocycles may endow it with new responsiveness and bioactivities, as well as new types of host-guest chemistry.