Linear Free-Energy Relationships Applied to the C-13 NMR Chemical Shifts in 4-Substituted N-[1-(Pyridine-3-and-4-yl)ethylidene]anilines
Само за регистроване кориснике
2014
Аутори
Rančić, MilicaTrišović, Nemanja
Milčić, Miloš
Jovanović, Maja
Jovanović, Bratislav Ž.
Marinković, Aleksandar
Чланак у часопису (Објављена верзија)
Метаподаци
Приказ свих података о документуАпстракт
Two series of 4-substituted N-[1-(pyridine-3- and -4-yl)ethylidene]anilines have been synthesized using different methods of conventional and microwave-assisted synthesis, and linear free-energy relationships have been applied to the C-13 NMR chemical shifts of the carbon atoms of interest. The substituent-induced chemical shifts have been analyzed using single substituent parameter and dual substituent parameter methods. The presented correlations describe satisfactorily the field and resonance substituent effects having similar contributions for C1 and the azomethine carbon, with exception of the carbon atom in para position to the substituent X. In both series, negative values have been found for C1 atom (reverse substituent effect). Quantum chemical calculations of the optimized geometries at MP2/6-31G++(d,p) level, together with C-13 NMR chemical shifts, give a better insight into the influence of the molecular conformation on the transmission of electronic substituent effects. Th...e comparison of correlation results for different series of imines with phenyl, 4-nitrophenyl, 2-pyridyl, 3-pyridyl, 4-pyridyl group attached at the azomethine carbon with the results for 4-substituted N-[1-(pyridine-3- and -4-yl)ethylidene]anilines for the same substituent set (X) indicates that a combination of the influences of electronic effects of the substituent X and the (1)-unit can be described as a sensitive balance of different resonance structures.
Извор:
Journal of Heterocyclic Chemistry, 2014, 51, 5, 1442-1451Издавач:
- Wiley-Blackwell, Hoboken
Финансирање / пројекти:
- Проучавање синтезе, структуре и активности органских једињења природног и синтетског порекла (RS-MESTD-Basic Research (BR or ON)-172013)
DOI: 10.1002/jhet.1752
ISSN: 0022-152X
WoS: 000342746900035
Scopus: 2-s2.0-85028227018
Институција/група
Tehnološko-metalurški fakultetTY - JOUR AU - Rančić, Milica AU - Trišović, Nemanja AU - Milčić, Miloš AU - Jovanović, Maja AU - Jovanović, Bratislav Ž. AU - Marinković, Aleksandar PY - 2014 UR - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2732 AB - Two series of 4-substituted N-[1-(pyridine-3- and -4-yl)ethylidene]anilines have been synthesized using different methods of conventional and microwave-assisted synthesis, and linear free-energy relationships have been applied to the C-13 NMR chemical shifts of the carbon atoms of interest. The substituent-induced chemical shifts have been analyzed using single substituent parameter and dual substituent parameter methods. The presented correlations describe satisfactorily the field and resonance substituent effects having similar contributions for C1 and the azomethine carbon, with exception of the carbon atom in para position to the substituent X. In both series, negative values have been found for C1 atom (reverse substituent effect). Quantum chemical calculations of the optimized geometries at MP2/6-31G++(d,p) level, together with C-13 NMR chemical shifts, give a better insight into the influence of the molecular conformation on the transmission of electronic substituent effects. The comparison of correlation results for different series of imines with phenyl, 4-nitrophenyl, 2-pyridyl, 3-pyridyl, 4-pyridyl group attached at the azomethine carbon with the results for 4-substituted N-[1-(pyridine-3- and -4-yl)ethylidene]anilines for the same substituent set (X) indicates that a combination of the influences of electronic effects of the substituent X and the (1)-unit can be described as a sensitive balance of different resonance structures. PB - Wiley-Blackwell, Hoboken T2 - Journal of Heterocyclic Chemistry T1 - Linear Free-Energy Relationships Applied to the C-13 NMR Chemical Shifts in 4-Substituted N-[1-(Pyridine-3-and-4-yl)ethylidene]anilines EP - 1451 IS - 5 SP - 1442 VL - 51 DO - 10.1002/jhet.1752 ER -
@article{ author = "Rančić, Milica and Trišović, Nemanja and Milčić, Miloš and Jovanović, Maja and Jovanović, Bratislav Ž. and Marinković, Aleksandar", year = "2014", abstract = "Two series of 4-substituted N-[1-(pyridine-3- and -4-yl)ethylidene]anilines have been synthesized using different methods of conventional and microwave-assisted synthesis, and linear free-energy relationships have been applied to the C-13 NMR chemical shifts of the carbon atoms of interest. The substituent-induced chemical shifts have been analyzed using single substituent parameter and dual substituent parameter methods. The presented correlations describe satisfactorily the field and resonance substituent effects having similar contributions for C1 and the azomethine carbon, with exception of the carbon atom in para position to the substituent X. In both series, negative values have been found for C1 atom (reverse substituent effect). Quantum chemical calculations of the optimized geometries at MP2/6-31G++(d,p) level, together with C-13 NMR chemical shifts, give a better insight into the influence of the molecular conformation on the transmission of electronic substituent effects. The comparison of correlation results for different series of imines with phenyl, 4-nitrophenyl, 2-pyridyl, 3-pyridyl, 4-pyridyl group attached at the azomethine carbon with the results for 4-substituted N-[1-(pyridine-3- and -4-yl)ethylidene]anilines for the same substituent set (X) indicates that a combination of the influences of electronic effects of the substituent X and the (1)-unit can be described as a sensitive balance of different resonance structures.", publisher = "Wiley-Blackwell, Hoboken", journal = "Journal of Heterocyclic Chemistry", title = "Linear Free-Energy Relationships Applied to the C-13 NMR Chemical Shifts in 4-Substituted N-[1-(Pyridine-3-and-4-yl)ethylidene]anilines", pages = "1451-1442", number = "5", volume = "51", doi = "10.1002/jhet.1752" }
Rančić, M., Trišović, N., Milčić, M., Jovanović, M., Jovanović, B. Ž.,& Marinković, A.. (2014). Linear Free-Energy Relationships Applied to the C-13 NMR Chemical Shifts in 4-Substituted N-[1-(Pyridine-3-and-4-yl)ethylidene]anilines. in Journal of Heterocyclic Chemistry Wiley-Blackwell, Hoboken., 51(5), 1442-1451. https://doi.org/10.1002/jhet.1752
Rančić M, Trišović N, Milčić M, Jovanović M, Jovanović BŽ, Marinković A. Linear Free-Energy Relationships Applied to the C-13 NMR Chemical Shifts in 4-Substituted N-[1-(Pyridine-3-and-4-yl)ethylidene]anilines. in Journal of Heterocyclic Chemistry. 2014;51(5):1442-1451. doi:10.1002/jhet.1752 .
Rančić, Milica, Trišović, Nemanja, Milčić, Miloš, Jovanović, Maja, Jovanović, Bratislav Ž., Marinković, Aleksandar, "Linear Free-Energy Relationships Applied to the C-13 NMR Chemical Shifts in 4-Substituted N-[1-(Pyridine-3-and-4-yl)ethylidene]anilines" in Journal of Heterocyclic Chemistry, 51, no. 5 (2014):1442-1451, https://doi.org/10.1002/jhet.1752 . .