Reaction of Indole Carboxylic Acid/Amide with Propargyl Alcohols: [4+3]-Annulation, Unexpected 3-to 2-Carboxylate/Amide Migration, and Decarboxylative Cyclization
1-Methylindole-3-carboxamides react with substituted propargyl alcohols to afford lactams by [4 + 3]-annulation and carboxamide group migration to the indole-2-position. In contrast, indole-2-carboxylic acids/amides form fused seven membered lactones/lactams (oxepinoindolones/azepinoindolones) upon...
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| Veröffentlicht in: | Organic letters Jg. 21; H. 14; S. 5447 - 5451 |
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| Hauptverfasser: | , , |
| Format: | Journal Article |
| Sprache: | Englisch |
| Veröffentlicht: |
WASHINGTON
Amer Chemical Soc
19.07.2019
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| Schlagworte: | |
| ISSN: | 1523-7060, 1523-7052 |
| Online-Zugang: | Weitere Angaben |
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| Zusammenfassung: | 1-Methylindole-3-carboxamides react with substituted propargyl alcohols to afford lactams by [4 + 3]-annulation and carboxamide group migration to the indole-2-position. In contrast, indole-2-carboxylic acids/amides form fused seven membered lactones/lactams (oxepinoindolones/azepinoindolones) upon treatment with substituted propargyl alcohols using catalytic Cu(OTf)(2). Decarboxylative cyclization of 1-methylindole-2- or indole-3-carboxylic acids with substituted propargyl alcohols under Lewis (for 1-methylindole-2-carboxylic acid) or Bronsted (for 1-methylindole-3-carboxylic acid) acid catalysis gives the same 3,4-dihydrocyclopentaindoles, demonstrating 3- to 2-carboxylate migration in the latter case. |
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| ISSN: | 1523-7060 1523-7052 |
| DOI: | 10.1021/acs.orglett.9b01686 |