Quantitative insights into the role of halogen and triel bonds in the formation of isostructural co-crystals of 4-iodophenyl boronic acid

Abstract

Phenyl boronic acid, which exhibits structural similarity to carboxylic acid, forms a hydrogen-bonded homo-dimer. During the cocrystallization process, the hydrogen-bonded homodimer is often disrupted by the incorporation of coformers. In this study, we present two distinct cocrystals of 4-iodophenyl boronic acid: one with (iodoethynyl)benzene and the other with 1,4-diiodobenzene. Notably, in both cases, the hydrogen-bonded dimer remains unaffected. Instead, interactions between the coformers and 4-iodophenyl boronic acid are facilitated through halogen and triel bonds, and C–H⋯π interactions, resulting in the formation of isostructural solids. Furthermore, quantitative investigation of the halogen and triel bonds within the cocrystals was performed utilizing various approaches, including MESP, 2D fingerprint plot, 3D deformation density plot, QTAIM, and NBO analyses. These methods elucidate the intricate bonding interactions present in these systems, underscoring their complexity and significance.