Inter- vs. Intra-Molecular Hydrogen Bond in Complexes of Nitrophthalic Acids with Pyridine

• Published in: International journal of molecular sciences Vol. 24; no. 6; p. 5248
• Main Authors: Jóźwiak, Kinga, Jezierska, Aneta, Panek, Jarosław J, Kochel, Andrzej, Filarowski, Aleksander
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 09.03.2023; MDPI
• Subjects: Acids; Alzheimer's disease; Bonds; Carboxyl group; Chemical bonds; Density functional theory; Density functionals; Hydrogen; Hydrogen - chemistry; hydrogen bond; Hydrogen Bonding; Hydrogen bonds; Isomerism; Molecular dynamics; Molecular Dynamics Simulation; phthalic acid; Proteins; proton dynamics; Protons; Pyridine; Pyridines; Pyridines - chemistry; Simulation; steric repulsion; X-ray; United Kingdom; Germany; steric repulsion; DFT; proton dynamics; IR; Raman; CPMD; X-ray; phthalic acid; hydrogen bond
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms24065248

This study covers the analysis of isomeric forms of nitrophthalic acids with pyridine. This work dwells on the complementary experimental (X-ray, IR and Raman) and theoretical (Car-Parrinello Molecular Dynamics (CPMD) and Density Functional Theory (DFT)) studies of the obtained complexes. The conducted studies showed that steric repulsion between the nitro group in ortho-position and the carboxyl group causes significant isomeric changes. Modeling of the nitrophthalic acid-pyridine complex yielded a short strong intramolecular hydrogen bond (SSHB). The transition energy from the isomeric form with an intermolecular hydrogen bond to the isomeric form with an intramolecular hydrogen bond was estimated.