Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-Oxide
An electrochemical reaction between quinoline <i>N</i>-oxides and morpholine was developed by using Cu(OAc)<sub>2</sub> as a catalyst, generating products of 4-aminoquinoline <i>N</i>-oxides in CH<sub>2</sub>Cl<sub>2</sub> or 2-aminoquinoli...
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2023-09-01
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| author | Egor L. Dolengovski Tatyana V. Gryaznova Oleg G. Sinyashin Elena L. Gavrilova Kirill V. Kholin Yulia H. Budnikova |
| author_facet | Egor L. Dolengovski Tatyana V. Gryaznova Oleg G. Sinyashin Elena L. Gavrilova Kirill V. Kholin Yulia H. Budnikova |
| author_sort | Egor L. Dolengovski |
| collection | DOAJ |
| description | An electrochemical reaction between quinoline <i>N</i>-oxides and morpholine was developed by using Cu(OAc)<sub>2</sub> as a catalyst, generating products of 4-aminoquinoline <i>N</i>-oxides in CH<sub>2</sub>Cl<sub>2</sub> or 2-aminoquinoline <i>N</i>-oxides in CH<sub>3</sub>CN in good yields. With an increase in the amount of electricity passed, the product deoxygenates with the formation of aminoquinolines. The advantages of the reaction are mild conditions, room temperature, the use of morpholine rather than its derivatives, and the ability to control the process when the electrolysis conditions change. Bisubstituted quinoline has also been obtained. The redox properties of both individual participants of C–H/N–H cross-coupling and multicomponent systems were established by voltammetry and EPR methods. For the first time, the EPR spectrum of the morpholine radical was recorded at room temperature, and its magnetic resonance parameters were determined in CH<sub>2</sub>Cl<sub>2</sub>. Mechanisms for the catalytic reaction have been proposed. This is a simple and easy-to-perform method for introducing a morpholine substituent, important in medicinal chemistry and other fields, by C–H/N–H cross-coupling. |
| first_indexed | 2024-03-10T22:56:50Z |
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| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-10T22:56:50Z |
| publishDate | 2023-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Catalysts |
| spelling | doaj.art-fe670717f47743b093ef233b7c25b1c62023-11-19T09:58:14ZengMDPI AGCatalysts2073-43442023-09-01139127910.3390/catal13091279Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-OxideEgor L. Dolengovski0Tatyana V. Gryaznova1Oleg G. Sinyashin2Elena L. Gavrilova3Kirill V. Kholin4Yulia H. Budnikova5Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, 420088 Kazan, RussiaArbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, 420088 Kazan, RussiaArbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, 420088 Kazan, RussiaOrganic Chemistry Department, Kazan National Research Technological University, 68 Karl Marx Street, 420015 Kazan, RussiaOrganic Chemistry Department, Kazan National Research Technological University, 68 Karl Marx Street, 420015 Kazan, RussiaArbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, 420088 Kazan, RussiaAn electrochemical reaction between quinoline <i>N</i>-oxides and morpholine was developed by using Cu(OAc)<sub>2</sub> as a catalyst, generating products of 4-aminoquinoline <i>N</i>-oxides in CH<sub>2</sub>Cl<sub>2</sub> or 2-aminoquinoline <i>N</i>-oxides in CH<sub>3</sub>CN in good yields. With an increase in the amount of electricity passed, the product deoxygenates with the formation of aminoquinolines. The advantages of the reaction are mild conditions, room temperature, the use of morpholine rather than its derivatives, and the ability to control the process when the electrolysis conditions change. Bisubstituted quinoline has also been obtained. The redox properties of both individual participants of C–H/N–H cross-coupling and multicomponent systems were established by voltammetry and EPR methods. For the first time, the EPR spectrum of the morpholine radical was recorded at room temperature, and its magnetic resonance parameters were determined in CH<sub>2</sub>Cl<sub>2</sub>. Mechanisms for the catalytic reaction have been proposed. This is a simple and easy-to-perform method for introducing a morpholine substituent, important in medicinal chemistry and other fields, by C–H/N–H cross-coupling.https://www.mdpi.com/2073-4344/13/9/1279coppercatalysisradicalmorpholine<i>N</i>-oxideselectrochemistry |
| spellingShingle | Egor L. Dolengovski Tatyana V. Gryaznova Oleg G. Sinyashin Elena L. Gavrilova Kirill V. Kholin Yulia H. Budnikova Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-Oxide Catalysts copper catalysis radical morpholine <i>N</i>-oxides electrochemistry |
| title | Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-Oxide |
| title_full | Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-Oxide |
| title_fullStr | Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-Oxide |
| title_full_unstemmed | Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-Oxide |
| title_short | Morpholine Radical in the Electrochemical Reaction with Quinoline <i>N</i>-Oxide |
| title_sort | morpholine radical in the electrochemical reaction with quinoline i n i oxide |
| topic | copper catalysis radical morpholine <i>N</i>-oxides electrochemistry |
| url | https://www.mdpi.com/2073-4344/13/9/1279 |
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