Synthesis, crystal structure, Hirshfeld surface investigation and comparative DFT studies of ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate

• Published in: BMC chemistry Vol. 16; no. 1; p. 18
• Main Authors: Haroon, Muhammad, Akhtar, Tashfeen, Yousuf, Muhammad, Tahir, Muhammad Nawaz, Rasheed, Lubna, Zahra, Syeda Saniya, Haq, Ihsan ul, Ashfaq, Muhammad
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 22.03.2022; BioMed Central Ltd; Springer Nature B.V; BMC
• Subjects: Anti-oxidant; Antiinfectives and antibacterials; Antioxidants; Carboxylates; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Comparative analysis; Conjugation; Crystal structure; Crystals; Density functional theory; DFT calculations; Functional groups; Geometry; Hydrogen; Hydrogen bonding; Investigations; Microorganisms; Molecular orbitals; Nitrogen dioxide; NMR; Nuclear magnetic resonance; Oxidizing agents; Quantum chemistry; Refluxing; Research Article; Single crystals; Spectrometry; Spectroscopy; Structure; Surface analysis (chemical); Thiazole; Vibrational spectra; XRD; Spectroscopy; XRD; Anti-oxidant; Thiazole; DFT calculations
• ISSN: 2661-801X; 2661-801X
• DOI: 10.1186/s13065-022-00805-1

The ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate ( 1 ), a thiazole ester, was synthesized by refluxing 1-(2-nitrobenzylidene)thiosemicarbazide and ethyl bromopyruvate. The compound is characterized by spectrometric, spectroscopic and single crystal (SC-XRD) techniques. Non-covalent interactions that are responsible for crystal packing are explored by Hirshfeld surface analysis. All theoretical calculations were performed by DFT quantum chemical methods using 6-311G(d,p) and cc-pVTZ basis sets and compared. Theoretical harmonic frequencies of ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate ( 1 ) were optimized. Confirmation of hydrogen bonding sites was analyzed by molecular electrostatic potential (MEP) and Mulliken population analysis. The vibrational frequencies of characteristic functional groups and chemical shifts were found in good agreement with experimental assignments. Frontier molecular orbital (FMO) revealed relatively small HOMO–LUMO (highest occupied molecular orbital-lowest unoccupied molecular orbital) gape, which speaks off the nearly planar geometry and extended conjugation, as compared to the substituents with no conjugation possible. It has also been observed that –NO 2 substituent plays a vital role for this relatively small HOMO–LUMO gape and overall electronic properties when compared with similar thiazole carboxylates ( 2–6 , Table 6 ). Ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1) was also evaluated for its anti-oxidant and anti-microbial activities. Graphical Abstract