Atom-Efficient Halogen–Halogen Interactions Assist One-, Two-, and Three-Dimensional Molecular Zippers

Abstract

Unprecedented multimodal weak interactions are quintessential to create novel supramolecular topologies. Among the plethora of weak interactions, halogen–halogen (X···X) interactions offer innovative possibilities for the design of multidimensional scaffolds. Herein, we chronicle the state-of-the-art 1D, 2D, and 3D zipper motifs steered by distinct interhalogen interactions, revealing the potential of halogen bonding in engineering biomimetic molecular assemblies. Recurring units of Br4 synthon, framed by type I and type II atom efficient X···X interactions in a dibromonaphthathiazole derivative, 2,4-dibromo-5-ethoxynaphtho[1,2-d]thiazole (NTB2), forges the molecular zipper. On the basis of the semiclassical Marcus theory of charge transport, the NTB2 zipper assembly displays selective electron transport along the type II X···X bonded direction. Band structure analysis classified the crystalline NTB2 as a wide band gap semiconductor with a band gap of 2.80 eV, respectively. The robustness of the X···X mediated zipper motif opens up new avenues in the development of advanced functional materials.