Regioselective preparation and NMR spectroscopy study of 2-chloro-4-ethoxy-quinoline for the synthesis of 2-((3-aminopropyl)amino)quinolin-4(1H)-one
© 2019 John Wiley & Sons, Ltd.
Veröffentlicht in: | Magnetic resonance in chemistry : MRC. - 1985. - 58(2020), 4 vom: 30. Apr., Seite 295-304 |
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1. Verfasser: | |
Weitere Verfasser: | , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2020
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Zugriff auf das übergeordnete Werk: | Magnetic resonance in chemistry : MRC |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't 1H─15N HMBC H/D exchange NMR bederocin quinolines quinolones |
Zusammenfassung: | © 2019 John Wiley & Sons, Ltd. Herein, we describe the C4-ethoxylation of 2,4-dichloroquinoline to prepare 2-chloro-4-ethoxy-quinoline (3), which is a prominent intermediate used for the synthesis of 2-substituted quinolones. To achieve this goal, we studied different conditions for the reaction between 2,4-dichloroquinoline and sodium ethoxide. We discovered that the use of 18-crown-6 ether as an additive and dimethylformamide as the reaction solvent allowed us to obtain the desired product 3 in very good yield and selectivity. In addition, a definitive distinction between the C2 and C4 ethoxylation products was achieved using 1 H─15 N heteronuclear multiple bond correlation. Compound 3 is an intermediate used for the synthesis of 2-((3-aminopropyl)amino)quinolin-4(1H)-one, which displays peculiar behavior during 1 H nuclear magnetic resonance analysis, such as the broadening of the H8 singlet and unexpected deuteration at the C8-position. Effort has been dedicated to understand these findings |
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Beschreibung: | Date Completed 06.03.2020 Date Revised 06.03.2020 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1097-458X |
DOI: | 10.1002/mrc.4980 |