A straightforward access to 3-trifluoromethyl-1H-indazoles via (3+2)-cycloaddition of arynes with nitrile imines derived from trifluoroacetonitrile
| Autor: | Greta Utecht-Jarzyńska, Marcin Jasiński, Grzegorz Mlostoń, Anna Kowalczyk |
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| Rok vydání: | 2021 |
| Předmět: |
Indazole
Trifluoromethyl Nitrile 010405 organic chemistry Organic Chemistry Intermolecular force Alkylation 010402 general chemistry 01 natural sciences Biochemistry Combinatorial chemistry Aryne Cycloaddition 0104 chemical sciences Inorganic Chemistry Acylation chemistry.chemical_compound chemistry Environmental Chemistry Physical and Theoretical Chemistry |
| Zdroj: | Journal of Fluorine Chemistry. 241:109691 |
| ISSN: | 0022-1139 |
| Popis: | In situ generated arynes react with nitrile imines derived from trifluoroacetonitrile at 0 °C in THF solutions yielding 3-trifluoromethyl-1H-indazole derivatives as the only intermolecular products. The reaction corresponds the expected (3 + 2)-cycloadditions which belong to the Type III (inverse-electron-demand) of Sustmann’s classification. Subsequent CAN-mediated dearylation of the model N-(p-methoxy)phenyl indazole leads to N-unsubstituted analogue, which easily undergoes alkylation and acylation reactions. Presented protocol offers a superior method for preparation of the 3-CF3 substituted indazole derivatives. |
| Databáze: | OpenAIRE |
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