Ionic Recognition Controlled by Conformational Change: A DFT Investigation

Author(s)

Orenha, Renato P. ; Andrade, Ana L. O. ; Rocha, Renato G. ; Munoz-Castro, Alvaro ; Santos, Thiago F. ; Piotrowski, MauricioJ. ; Caramori, Giovanni F. ; Parreira, Renato L. T.

• Document type: Journal article
• Source: ACS OMEGA; v. N/A, p. 9-pg., 2025-04-16.

Abstract

Ions play a crucial role in the production of important materials and are associated with various health and environmental issues. Noncovalent interactions serve as fundamental tools for controlling the availability of cations and/or anions. Herein, we investigate the ability of two conformations of the 2,6-bis(1,2,3-triazol-4-yl)pyridine molecule to recognize cations (1), such as Li+, Na+, or K+, and anions (2), including F-, Cl-, or Br-. EDA-NOCV analysis demonstrates that the conformers preferentially recognize ions based on the size of the cations (K+ -> Na+ -> Li+) and anions (Br- -> Cl- -> F-). The preferential interaction with smaller cations (and anions) arises from the more attractive electrostatic and orbital interactions (N<middle dot><middle dot><middle dot>.cation and C-H<middle dot><middle dot><middle dot>.anion bonds). The presence of electron-donor groups (-NH2) in the first conformer (1) enhances cation recognition through stronger electrostatic N<middle dot><middle dot><middle dot>.cation interactions. Conversely, the presence of electron-acceptor groups (-NO2) in the second conformer (2) facilitates anion recognition via more favorable electrostatic, orbital, and dispersion C-H<middle dot><middle dot><middle dot>.anion interactions. Cation recognition is found to be more favorable in the first conformer than anion recognition in the second due to more attractive electrostatic energy and/or less Pauli repulsive energy associated with (O or primarily N)<middle dot><middle dot><middle dot>.cation interactions in 1 <middle dot><middle dot><middle dot>.cations compared to (N or mainly C)-H<middle dot><middle dot><middle dot>.anion bonds in 2 <middle dot><middle dot><middle dot>.anions. These findings provide significant insights into the mechanisms of cation and/or anion recognition through different conformations using the same base structure and can inform the design of molecules with enhanced functionalities. (AU)

• FAPESP's process: 11/07623-8 - The use of quantum-mechanical methods to study the bonds and chemical interactions in self-organizing systems with applications in catalysis, medicinal chemistry, electrochromism, energy storage and conversion
• Grantee: Renato Luis Tame Parreira
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 24/11041-4 - Computational Study of Nutrient Release through Smart Micro and Nanogels for Agricultural Purposes
• Grantee: Renato Pereira Orenha
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors