Assembly of Multi-Dimensional Molecular Networks through Self-Complementary Halogen-Bonded Tectons

Abstract

A high-fidelity and self-complementary halogen bonding moiety, 2-iodooxazole, was identified using density functional theory-based calculations. Installation of 2-iodooxazole on two geometrically complementary cores using a two-step synthetic approach gave the tectons 1,4-bis(2-iodooxazol-5-yl)benzene (BIOx) and 1,4-bis(2-iodooxazol-5-yl)-2,3,5,6-tetrafluorobenzene (FIOx). Single crystal X-ray diffraction studies have shown that both BIOx and FlOx possess the requisite strength and geometry to assemble into crystalline, multi-dimensional halogen-bonded networks. Control of assembly through chemically intuitive solvent conditions permitted the deliberate assembly of one, two, or three-dimensional halogen-bonded networks. This work demonstrates that through careful design of tectons and crystal-growth conditions, halogen-bonded networks may meet the bar set by hydrogen-bonded analogues.