Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups
The effect of ortho′-substituted side chains bearing nucleophilic groups such as CH 2 OH, CH 2 NHR, and CO 2 H on the reactivity of anodically generated 4-methoxy- and 3,4-dimethoxystilbene cation radicals was investigated, and results were compared with those of substrates where the nucleophilic gr...
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| Format: | Article |
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American Chemical Society
2018
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| _version_ | 1796961583201517568 |
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| author | Chong, Kam Weng Thomas, Noel Francis Low, Yun Yee Kam, Toh Seok |
| author_facet | Chong, Kam Weng Thomas, Noel Francis Low, Yun Yee Kam, Toh Seok |
| author_sort | Chong, Kam Weng |
| collection | UM |
| description | The effect of ortho′-substituted side chains bearing nucleophilic groups such as CH 2 OH, CH 2 NHR, and CO 2 H on the reactivity of anodically generated 4-methoxy- and 3,4-dimethoxystilbene cation radicals was investigated, and results were compared with those of substrates where the nucleophilic groups such as OH and NHR are directly attached to the aromatic ring. It was found that when ortho′-substituted groups such as CH 2 OH or CH 2 NHR are present in the other ring, only direct intramolecular cation-nucleophile reactions occur to give bisbenzopyrans or bisisoquinolines. Crossover products (previously obtained when the ortho′ substituents were OH and NH 2 ) such as the fused benzoxepanes/fused benzoazepanes were not formed. When the ortho′ substituent is COOH, direct intramolecular cation-nucleophile reaction occurs to give the corresponding bis-δ-lactones in high yield. The presence of an additional 3-methoxy substituent resulted in the formation of other fused polycyclic products due to competing aromatic substitution reactions. Reaction pathways leading to the different products and reasons for the difference in behavior shown by the present stilbenes are presented. The results have provided additional insight into the reactivity and behavior of anodically generated stilbene cation radicals. |
| first_indexed | 2024-03-06T05:56:16Z |
| format | Article |
| id | um.eprints-22206 |
| institution | Universiti Malaya |
| last_indexed | 2024-03-06T05:56:16Z |
| publishDate | 2018 |
| publisher | American Chemical Society |
| record_format | dspace |
| spelling | um.eprints-222062019-09-04T04:18:07Z http://eprints.um.edu.my/22206/ Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups Chong, Kam Weng Thomas, Noel Francis Low, Yun Yee Kam, Toh Seok Q Science (General) QD Chemistry The effect of ortho′-substituted side chains bearing nucleophilic groups such as CH 2 OH, CH 2 NHR, and CO 2 H on the reactivity of anodically generated 4-methoxy- and 3,4-dimethoxystilbene cation radicals was investigated, and results were compared with those of substrates where the nucleophilic groups such as OH and NHR are directly attached to the aromatic ring. It was found that when ortho′-substituted groups such as CH 2 OH or CH 2 NHR are present in the other ring, only direct intramolecular cation-nucleophile reactions occur to give bisbenzopyrans or bisisoquinolines. Crossover products (previously obtained when the ortho′ substituents were OH and NH 2 ) such as the fused benzoxepanes/fused benzoazepanes were not formed. When the ortho′ substituent is COOH, direct intramolecular cation-nucleophile reaction occurs to give the corresponding bis-δ-lactones in high yield. The presence of an additional 3-methoxy substituent resulted in the formation of other fused polycyclic products due to competing aromatic substitution reactions. Reaction pathways leading to the different products and reasons for the difference in behavior shown by the present stilbenes are presented. The results have provided additional insight into the reactivity and behavior of anodically generated stilbene cation radicals. American Chemical Society 2018 Article PeerReviewed Chong, Kam Weng and Thomas, Noel Francis and Low, Yun Yee and Kam, Toh Seok (2018) Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups. The Journal of Organic Chemistry, 83 (24). pp. 15087-15100. ISSN 0022-3263, DOI https://doi.org/10.1021/acs.joc.8b02360 <https://doi.org/10.1021/acs.joc.8b02360>. https://doi.org/10.1021/acs.joc.8b02360 doi:10.1021/acs.joc.8b02360 |
| spellingShingle | Q Science (General) QD Chemistry Chong, Kam Weng Thomas, Noel Francis Low, Yun Yee Kam, Toh Seok Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups |
| title | Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups |
| title_full | Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups |
| title_fullStr | Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups |
| title_full_unstemmed | Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups |
| title_short | Reactivity of Anodically Generated 4-Methoxystilbene Cation Radicals: The Influence of Ortho-Substituted Hydroxymethyl, Aminomethyl, and Carboxylic Acid Groups |
| title_sort | reactivity of anodically generated 4 methoxystilbene cation radicals the influence of ortho substituted hydroxymethyl aminomethyl and carboxylic acid groups |
| topic | Q Science (General) QD Chemistry |
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