Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations
In this study, a series of asymmetric aryl 1,3-dicarbonyl compounds were synthesized and their enol forms were observed via experimental data and theoretical calculations. According to the 1H- and 13C-NMR results, all the investigated compounds were found as a single enol form in CDCl3 solution. Mor...
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| Format: | Article |
| Language: | English |
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Serbian Chemical Society
2018-01-01
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| Series: | Journal of the Serbian Chemical Society |
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| Online Access: | http://www.doiserbia.nb.rs/img/doi/0352-5139/2018/0352-51391800053T.pdf |
| _version_ | 1811317604452663296 |
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| author | Tan Meltem Bildirici İshak Mengeş Nurettin |
| author_facet | Tan Meltem Bildirici İshak Mengeş Nurettin |
| author_sort | Tan Meltem |
| collection | DOAJ |
| description | In this study, a series of asymmetric aryl 1,3-dicarbonyl compounds were synthesized and their enol forms were observed via experimental data and theoretical calculations. According to the 1H- and 13C-NMR results, all the investigated compounds were found as a single enol form in CDCl3 solution. Moreover, their HMBC spectra were applied to identify the observed enol forms and correlations between certain protons and carbon atoms were considered. The dihedral angles of the asymmetric compounds that have aryl units on both sides were calculated by DFT to understand the reason for the observed enol forms. Small dihedral angles caused longer conjugation, resulting in more stable compounds and it was found that the observed enol forms were based on small dihedral angles, namely, resonance is the driving force. Furthermore, the compounds possessing both aryl and alkyl moieties prefer the enol form towards the aromatic ring side due to longer conjugation. |
| first_indexed | 2024-04-13T12:09:57Z |
| format | Article |
| id | doaj.art-eaae265d1c134e5d86301d87346b631c |
| institution | Directory Open Access Journal |
| issn | 0352-5139 1820-7421 |
| language | English |
| last_indexed | 2024-04-13T12:09:57Z |
| publishDate | 2018-01-01 |
| publisher | Serbian Chemical Society |
| record_format | Article |
| series | Journal of the Serbian Chemical Society |
| spelling | doaj.art-eaae265d1c134e5d86301d87346b631c2022-12-22T02:47:30ZengSerbian Chemical SocietyJournal of the Serbian Chemical Society0352-51391820-74212018-01-0183995396810.2298/JSC010318053T0352-51391800053TDetermination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculationsTan Meltem0Bildirici İshak1Mengeş Nurettin2Van Yüzüncü Yıl University, Faculty of Pharmacy, Van, TurkeyVan Yüzüncü Yıl University, Faculty of Pharmacy, Van, TurkeyVan Yüzüncü Yıl University, Faculty of Pharmacy, Van, TurkeyIn this study, a series of asymmetric aryl 1,3-dicarbonyl compounds were synthesized and their enol forms were observed via experimental data and theoretical calculations. According to the 1H- and 13C-NMR results, all the investigated compounds were found as a single enol form in CDCl3 solution. Moreover, their HMBC spectra were applied to identify the observed enol forms and correlations between certain protons and carbon atoms were considered. The dihedral angles of the asymmetric compounds that have aryl units on both sides were calculated by DFT to understand the reason for the observed enol forms. Small dihedral angles caused longer conjugation, resulting in more stable compounds and it was found that the observed enol forms were based on small dihedral angles, namely, resonance is the driving force. Furthermore, the compounds possessing both aryl and alkyl moieties prefer the enol form towards the aromatic ring side due to longer conjugation.http://www.doiserbia.nb.rs/img/doi/0352-5139/2018/0352-51391800053T.pdfenol tautomerismdihedral angleHMBC correlation |
| spellingShingle | Tan Meltem Bildirici İshak Mengeş Nurettin Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations Journal of the Serbian Chemical Society enol tautomerism dihedral angle HMBC correlation |
| title | Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations |
| title_full | Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations |
| title_fullStr | Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations |
| title_full_unstemmed | Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations |
| title_short | Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations |
| title_sort | determination of the enol form of asymmetric 1 3 dicarbonyl compounds 2d hmbc nmr data and dft calculations |
| topic | enol tautomerism dihedral angle HMBC correlation |
| url | http://www.doiserbia.nb.rs/img/doi/0352-5139/2018/0352-51391800053T.pdf |
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