A1 Journal article (refereed)
4-Methyl/Phenyl-1,2,5,6-tetraazafluoranthen-3(2H)-ones Synthesis : Mechanistic Pathway Study and Single-Crystal X-ray Analysis of the Intermediates (2023)

Sarhan, A. A. M., Haukka, M., Barakat, A., Soliman, S. M., Boraei, A. T. A., Sopaih, M., & Salama, E. E. (2023). 4-Methyl/Phenyl-1,2,5,6-tetraazafluoranthen-3(2H)-ones Synthesis : Mechanistic Pathway Study and Single-Crystal X-ray Analysis of the Intermediates. Crystals, 13(11), 1537. https://doi.org/10.3390/cryst13111537

JYU authors or editors

Publication details

All authors or editors: Sarhan, Ahmed A. M.; Haukka, Matti; Barakat, Assem; Soliman, Saied M.; Boraei, Ahmed T. A.; Sopaih, Manar; Salama, Eid E.

Journal or series: Crystals

eISSN: 2073-4352

Publication year: 2023

Publication date: 26/10/2023

Volume: 13

Issue number: 11

Pages range: 1537

Publisher: MDPI

Publication country: Switzerland

Publication language: English

DOI: https://doi.org/10.3390/cryst13111537

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/91832

Abstract

The synthesis of 4-methyl/phenyl-1,2,5,6-tetraazafluoranthen-3(2H)-one 4 and 7 has been reported with ninhydrin via a reaction first with ethyl acetoacetate or ethyl benzoylacetate and then a reaction of the resultant esters with hydrazine hydrate. The mechanism of hydrazinolysis and cyclization to obtain tetraazafluoranthen-3(2H)-ones is ambiguous, and the previously proposed mechanism was not based on facts because the actual intermediates were not isolated. Herein, the important intermediates involved in the hydrazinolysis–cyclization mechanistic pathway were isolated and characterized using NMR and X-ray single-crystal analysis. The intermediates demonstrate that the reaction carried out via two hydrazinolysis–cyclization reactions, the first of which includes the condensation of one hydrazine molecule with two ketone groups and the second of which includes the reaction of another hydrazine molecule with the ester and then condensation with the other ketone group. The stability of hydrazide 11 enabled the hydrazine to reduce the carbonyl of the ketone group to form 12 via a Wolff–Kishner-like reduction. The structure of the three intermediates was confirmed using X-ray crystallographic analysis. It was found that the three fused ring systems deviated from planarity to different extents, with their deviation from being coplanar reaching up to 5.3°. The possible non-covalent interactions which control the molecular packing of these intermediates were elucidated with the aid of Hirshfeld analysis.

Keywords: x-ray crystallography; X-ray radiation; reaction mechanisms; chemical synthesis

Free keywords: single-crystal X-ray; tetraazafluoranthen-3(2H)-one; reaction mechanism; Hirshfeld surface analysis

Contributing organizations

Ministry reporting: Yes

VIRTA submission year: 2023

JUFO rating: 1