Synthesis and conformational analysis of naphthoxazine-fused phenanthrene derivatives
- The synthesis of new phenanthr[9,10-e][1,3]oxazines was achieved by the direct coupling of 9-phenanthrol with cyclic imines in the modified aza-Friedel-Crafts reaction followed by the ring closure of the resulting bifunctional aminophenanthrols with formaldehyde. Aminophenanthrol-type Mannich bases were synthesised and transformed to phenanthr[9,10-e][1,3]oxazines via [4 + 2] cycloaddition. Detailed NMR structural analyses of the new polyheterocycles as well as conformational studies including Density Functional Theory (DFT) modelling were performed. The relative stability of ortho-quinone methides (o-QMs) was calculated, the geometries obtained were compared with the experimentally determined NMR structures, and thereby, the regioselectivity of the reactions has been assigned.
Author details: | Khadija Belasri, Leila Topal, Matthias HeydenreichORCiD, Andreas KochORCiDGND, Erich KleinpeterORCiDGND, Ferenc FulopORCiD, Istvan SzatmariORCiD |
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DOI: | https://doi.org/10.3390/molecules25112524 |
ISSN: | 1420-3049 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/32481689 |
Title of parent work (English): | Molecules |
Publisher: | MDPI |
Place of publishing: | Basel |
Publication type: | Article |
Language: | English |
Date of first publication: | 2020/05/28 |
Publication year: | 2020 |
Release date: | 2023/05/04 |
Tag: | DFT calculations; NMR; [4+2] cycloaddition; conformational analysis; cyclic imines; modified Mannich reaction; spectroscopy |
Volume: | 25 |
Issue: | 11 |
Article number: | 2524 |
Number of pages: | 15 |
Funding institution: | Hungarian Research Foundation (OTKA)Orszagos Tudomanyos Kutatasi; Alapprogramok (OTKA) [K-129037]; Ministry of National Economy, National; Research Development and Innovation Office [GINOP-2.3.2-15-2016-00038]; EUEuropean Commission [EFOP-3.6.1-16-2016-00008]; Ministry of Human; Capacities, Hungary [TUDFO/47138-1/2019] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
DDC classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Peer review: | Referiert |
Publishing method: | Open Access / Gold Open-Access |
DOAJ gelistet | |
License (German): | CC-BY - Namensnennung 4.0 International |