Harnessing Weak and Hydrogen Bonding Interactions for Tailored Crystal Formation: A Case Study of Diisopropylammonium Phenylsulfonate

Abstract

The thoughtful design of a supramolecular molecule constructed from NH···OS-type hydrogen bonds is commonly used to create molecular architectures useful for industrial and medical applications. Here, we report for the first time a hydrogen bonding strategy for the formation of a crystalline diisopropylammonium phenylsulfonate molecule. Crystallographic analysis revealed that the diisopropylammonium cation forms hydrogen bonds with the phenylsulfonate anion. Furthermore, the anion, acting as a hydrogen bond acceptor, facilitates bonding between anions and cations through N–H·O hydrogen bonds, resulting in a supramolecular crystalline structure. Each oxygen atom participates in at least two hydrogen bonds, either C–H···O or both C–H···O and N–H···O, leading to the formation of a three-dimensional structure. an experimental study was conducted to examine the properties of this new crystal, including assessing the suitability of various DFT methods and the necessary adjustments to accurately describe its structural and spectroscopic characteristics. Using the DFT/B3LYP method with the 6-311++G(d,p), 6-311G(d,p), and 6-311+G(d,p) basis sets, we performed theoretical vibrational frequency calculations and evaluated geometric parameters such as bond lengths and angles for the first time. The DFT approach for determining bond lengths and angles was performed using the B3LYP method. These values, which fall within the characteristic range of hydrogen bonds, are consistent with crystallographic data. The dipole moment, as well as the HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital) energies, were also determined. This metal-free and eco-friendly synthetic process for producing supramolecular molecules holds significant potential for applications in both industry and the pharmaceutical field.