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The three pyridazines, three naphthyridines and two azoles: effect of the position of the second heteroatom on pKaH of their eight conjugate acids

  • Sanjeev Rachuru ORCID logo , Devarakonda A. Padmavathi ORCID logo , Ravi Ramavath , Jagannadham Vandanapu ORCID logo EMAIL logo and Adam A. Skelton ORCID logo
Published/Copyright: November 9, 2022
Zeitschrift für Physikalische Chemie
From the journal Zeitschrift für Physikalische Chemie Volume 236 Issue 11-12

Abstract

In the present work, how the position of the second nitrogen in the conjugate acids of the three pyridazines viz., 1,2-pyridazine, 1,3-pyridazine (the pyrimidine) and 1,4-pyridazine (the pyrazine) and three naphthyridines viz., cinnoline, quinazoline and quinoxaline changes the pKaH systematically is taken up. They decrease nearly by a factor of half each time in the class of their own. In contrast there is an increase in the pKaH when we move from pyrazole to imidazole. The pKaH of pyrazole is less than imidazole by −4.45 units. Suitable explanations are given.

Keywords: 1,2-, 1,3-, 1,4-pyridazines; cinnoline; quinazoline; quinoxaline; azoles and pKaH
Corresponding author: Jagannadham Vandanapu, Department of Chemistry, Osmania University, Hyderabad 500007, India, E-mail:

Acknowledgments

The authors are grateful to the Centre for High Performance Computing (CHPC), Cape Town, South Africa, for their generous allocation of supercomputer time.

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: The research did not receive any specific funding.

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.

  4. Data availability: The supplementary file contains all the electronic input and output files (containing the IR and NMR spectra).

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Received: 2022-07-26
Accepted: 2022-10-20
Published Online: 2022-11-09
Published in Print: 2022-12-16

© 2022 Walter de Gruyter GmbH, Berlin/Boston

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https://doi.org/10.1515/zpch-2022-0111
Keywords for this article
1,2-, 1,3-, 1,4-pyridazines; cinnoline; quinazoline; quinoxaline; azoles and pKaH

Articles in the same Issue

  1. Frontmatter
  2. Original Papers
  3. Suppression of steel corrosion via some gemini cationic surfactant-based Schiff base: experimental and theoretical investigations
  4. Synthesis of poly (N-isopropyl acrylamide-co-2-acrylamido methylpropane sulfonic acid) hydrogel containing copper and nickel nanoparticles with easy recycling and efficient catalytic potential
  5. Eco-benign preparation of biosorbent using Momordica Charantia for the efficient removal of Cr(VI) ions from wastewater
  6. Oil mediated green synthesis of nano silver in the presence of surfactants for catalytic and food preservation application
  7. Adsorption properties of metal functionalized fullerene (C59Au, C59Hf, C59Ag, and C59Ir) nanoclusters for application as a biosensor for hydroxyurea (HXU): insight from theoretical computation
  8. Evaluation of diethylenetriaminepentaacetic acid modified chitosan immobilized in amino-carbmated alginate matrix as a low cost adsorbent for effective Cu(II) recovery
  9. Screening of four accelerated synthesized techniques in green fabrication of ZnO nanoparticles using Willow leaf extract
  10. Preparation and comparative evaluation of PVC/PbO and PVC/PbO/graphite based conductive nanocomposites
  11. Optical and topographic characteristics of silver films deposited from a colloidal solution on polyelectrolytes for IgG-FITC fluorescence analysis
  12. The three pyridazines, three naphthyridines and two azoles: effect of the position of the second heteroatom on pKaH of their eight conjugate acids
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  17. Review Article
  18. Photocatalytic hydrogen generation using TiO2: a state-of-the-art review
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