Aryl Boronic Acids in Columnar Stacked Co-crystalline Materials: Key-Factors Governing the Assembly with Quinones.

Abstract

The assembly of aryl boronic acids B with quinones Q into columnar mixed stacked materials, as previously observed in the solid-state, has been here subjected to a detailed theoretical analysis focusing on the properties of the isolated synthons (HOMO-LUMO energies, electron affinity, ionization potential, reorganization hole/electron energies, partial Hirshfeld atomic charges and conformation stabilities) as well as those of the 1 : 1 adducts (Hirshfeld analysis, IRI surfaces, Hirshfeld atomic charges, hydrogen bond and slipped stacked π-π contributions). The overall picture obtained throught this study shows an intricate pattern of interconnected factors contributing to the formation and stability of the Bx Qy adducts, and it unveils the importance of parameters such as HOMO-LUMO gap, polarization and charge transfer, in addition to the more evident hydrogen bond and slipped-stacked π-π interactions in the formation of 1 : 1 adducts. An explanation has been also given for the presence in some Bx Qy adducts of the rare anti-anti conformation for the BO-H group with respect to the most studied and common anti-syn conformation.