Aromaticity of the naphthalene ring substituted by formyl or nitro and secondary amine groups in peri and para positions has been investigated. HOMA (harmonic oscillator model of aromaticity) index of the naphthalene rings has been used to characterize the aromaticity of the investigated molecules. Ellipticity of C2-C3 (C6-C7) bonds, obtained by means of topological analysis of the electron density, has been used as a measure of the through-resonance effect between the para substituents. Dependence of the HOMA values on the rotation angle of formyl and nitro groups to the aromatic plane for naphthalene-1-carbaldehyde and their derivatives with dimethylamino group in para position has been analyzed. It has been shown that the nitro group has a stronger resonance effect and causes greater decrease of aromaticity than the formyl group only for planar or close to planar conformation. The attractive and repulsive peri interactions have been analyzed by using the QTAIM and NCI methods. Interrelation between the peri and para interactions has been discussed.
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http://dx.doi.org/10.1021/acs.jpca.6b11926 | DOI Listing |
Chemistry
January 2025
Shibaura Institute of Technology: Shibaura Kogyo Daigaku, Applied Chemistry, Fukasaku 307, Minuma-ku, 337-8570, Saitama, JAPAN.
A new Donor-Acceptor type pyrazinacene derivative (1) featuring strong ICT was synthesized by linking electron-donating triphenylamine (TPA) and electron-accepting CN groups via a pyrazinacene core. The compound exhibits a dramatic color change from greenish blue to red-violet upon selective recognition of naphthalene (3) to form a 1:1 co-crystal (1•3). This color change is induced by intermolecular CT between pyrazinacene and naphthalene's aromatic moieties, driven by π-hole···π interactions.
View Article and Find Full Text PDFJ Sep Sci
January 2025
Herbal and Traditional Medicines Research Center, Kerman University of Medical Sciences, Kerman, Iran.
Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic compounds resulting from incomplete burning of organic materials. This work describes the successful layer-by-layer fabrication of a novel zinc oxide nanocomposite made of zinc oxide nanoparticles, aniline, sodium dodecyl sulfate, and modified multi-walled carbon nanotubes on a stainless steel wire by electrodeposition. The coating and extraction conditions were screened, optimized, and validated using factorial design and central composite design, respectively.
View Article and Find Full Text PDFMolecules
January 2025
School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan.
Oxazole, a versatile and significant heteroarene, serves as a bridge between synthetic organic chemistry and applications in the medicinal, pharmaceutical, and industrial fields. Polycyclic aromatic compounds with amino groups substituted at the 2-position of an oxazole, such as 2-aminonaphthoxazoles, are expected to be functional probes, but their synthetic methods are extremely limited. Herein, we describe electrochemical reactions of 3-amino-2-naphthol or 3-amino-2-anthracenol and isothiocyanates in DMSO, using a graphite electrode as an anode and a platinum electrode as a cathode in the presence of potassium iodide (KI), which afford -arylnaphtho- and -arylanthra[2,3-]oxazol-2-amines via cyclodesulfurization.
View Article and Find Full Text PDFChem Biodivers
January 2025
Ocean University of China, School of Medicine and Pharmacy, 5 yushan road, shinan district, 266003, Qingdao, CHINA.
Three new naphthalene derivatives, strepthalenes A-C (1-3), and the known analogue (S)-DNPA (4), together with six previously reported anthraquinones (5-10), were isolated from the marine-derived Streptomyces sp. OUCMDZ-4182. Their structures were elucidated by detailed spectroscopic analysis and quantum chemical calculations.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Department of Chemistry, Indian Institute of Technology, Guwahati 781039, India.
Charge transfer (CT) states in polycyclic aromatic hydrocarbons play crucial roles in determining their electronic properties and their potential applications in organic electronics. In this work, we investigate the nature of the excited states in monomers and π-stacked dimers of azulene-fused naphthalene and anthracene systems, focusing on the interplay between structure and excited-state properties. Four different isomers for azulene-fused naphthalene (, , , and ) and anthracene (, , , and ) are considered.
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