| Theoretical Study of the Aromatic Properties and Reactivity of Carbon Atoms in Furan N-oxide derivatives |
| کد مقاله : 1036-ICOC |
| نویسندگان |
|
زینب محمدپور ضیائی *1، مسعود مختاری2 1دانشجو 2هیات علمی دانشگاه آزاد واحد رشت |
| چکیده مقاله |
| Furan N-oxide derivatives are a significant class of oxidized five-membered heterocycles. N-oxidation changes the electron distribution, aromaticity, and reactivity of the parent ring [1,2]. The introduction of the N-O functionality increases ring polarization, modifies the stability, and chemical behavior of these molecules. Understanding its effect on aromaticity and electronic structure is essential for predicting reactivity patterns and designing functionalized heteroaromatic systems [2]. Computational investigations were performed using Density Functional Theory at the B3LYP/6-311+G** level. Key descriptors were calculated, including NICS(0), NICS(1), and NICS(1)zz as magnetic aromaticity indicators, magnetic susceptibility (χm), and HOMA as a geometric aromaticity indicator. The analysis of molecular orbitals (MOs) was conducted to calculate the percentage of carbon atoms in the HOMO orbital through C2 population analysis [2]. N-oxidation significantly decreases the aromaticity of the furan system. The NICS values become less negative, and HOMA values decrease, reflecting a weakened diatropic ring current and reduced π-delocalization. Charge analysis indicates electron withdrawal from the ring toward the N-oxide moiety, especially at C2 and C5 positions, sites normally favored for electrophilic substitution. Furan N-oxide derivatives (Scheme 1) exhibit reduced aromaticity, altered electron distribution, and modified chemical reactivity compared to unsubstituted furan. N-oxidation introduces significant polarization into the ring system, ultimately decreasing stability and altering electrophilic and nucleophilic behavior. |
| کلیدواژه ها |
| Furan N-oxide, Nucleus Independent Chemical Shift (NICS), Reactivity |
| وضعیت: پذیرفته شده |