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An Efficient Approach to 2-CF3-Indoles Based on ortho-Nitrobenzaldehydes.

ABSTRACT: The catalytic olefination reaction of 2-nitrobenzaldehydes with CF3CCl3 afforded stereoselectively trifluoromethylated ortho-nitrostyrenes in up to 88% yield. The reaction of these alkenes with pyrrolidine permits preparation of α-CF3-β-(2-nitroaryl) enamines. Subsequent one pot reduction of nitro-group by Fe-AcOH-H2O system initiated intramolecular cyclization to afford 2-CF3-indoles. Target products can be prepared in up to 85% yields. Broad synthetic scope of the reaction was shown as well as some followed up transformations of 2- CF3-indole.

SUBMITTER: Muzalevskiy VM

PROVIDER: S-EPMC8658784 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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An Efficient Approach to 2-CF3-Indoles Based on ortho-Nitrobenzaldehydes.

Muzalevskiy Vasiliy M VM Sizova Zoia A ZA Abaev Vladimir T VT Nenajdenko Valentine G VG

Molecules (Basel, Switzerland) 20211204 23

The catalytic olefination reaction of 2-nitrobenzaldehydes with CF3CCl3 afforded stereoselectively trifluoromethylated ortho-nitrostyrenes in up to 88% yield. The reaction of these alkenes with pyrrolidine permits preparation of α-CF3-β-(2-nitroaryl) enamines. Subsequent one pot reduction of nitro-group by Fe-AcOH-H2O system initiated intramolecular cyclization to afford 2-CF3-indoles. Target products can be prepared in up to 85% yiel ...[more]

PMID: 34885948

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