Interplay of Hydrogen and Halogen Bonding in the Crystal Structures of 2,6‐Dihalogenated Phenols

Abstract

Hydrogen and halogen bonds are important anisotropic attractive interactions in the molecular crystalline state. 2,6dibromophenol (1) was analyzed by single-crystal X-ray diffraction for the first time. The intermolecular interaction pattern was studied by Hirshfeld surface analysis along with 2D fingerprint diagrams. The characteristic interactions that dominate the crystal packing are electrostatic type-II Br⋅⋅⋅Br interactions, OÀ H⋅⋅⋅O hydrogen bonds, and an offset parallel πstacking arrangement. Compound 1 was compared with 2,6difluoro-(2) and 2-bromo-6-chlorophenol (3) in terms of their interplay between hydrogen and halogen bonding. Whereas the OÀ H⋅⋅⋅O hydrogen bond is more pronounced in the lighter homologues, the halogen⋅⋅⋅halogen interaction becomes a particularly important directional, attractive interaction in the crystal structure of 2,6-dibromophenol.

Boat and Chair Shaped Hexahalogen Synthons

“…[39] The intermolecular Br interactions suggest that halogen and hydrogen bonding along with van der Waals interactions play the main roles in the threedimensional crystal packing of the two compounds. [40] The 'cooperative effects' in the weak intermolecular interactions across the studied crystals were visualized using the energy framework analysis as polarization, dispersion, electrostatic and repulsion components of total pairwise energy (Figure 2). [41,42] Frameworks represent molecular clusters around a central molecule that involve in direct interactions.…”

“…The major contribution is from the H⋅⋅⋅Br hydrogen bonds (42.7% for PBX and 37% for HBX) that are represented by a pair of symmetrical sharp spikes in the 2‐D fingerprint plots. The dominant Br⋅⋅⋅Br and H⋅⋅⋅Br interactions suggest that halogen and hydrogen bonding along with van der Waals interactions play the main roles in the three‐dimensional crystal packing of the two compounds [40] …”

Low and High Z′ Polymorphs of Dibenzyldiphenylsilane: A Hydrocarbon-Patterned Molecular Crystalline System

“…In our group, we are in general interested in questions about the interplay of hydrogen bonds, halogen bonds, and dispersion interactions in molecular crystals in order to better understand certain functional patterns with regard to their intermolecular interaction behavior. − In this context, we were caught by the interesting question of whether one specific polymorph can be reproducibly obtained through optimization of the crystallization process, even if the molecular crystal structures are held together exclusively by weak intermolecular interactions.…”