Ortho-hydrodefluorination of polyfluorinated 4-acetamidobiphenyls and synthesis of polyfluorinated 6-phenylquinolines

•Polyfluorinated 4-acetamidobiphenyls have been hydrodefluorinated with the Zn–NiCl2–2,2′-bipyridine–aq. DMF system.•Polyfluorinated 4-acetamido- and 4-aminobiphenyls unsubstituted ortho to the NHR (R = Ac, H) group have been synthesized.•The Skraup synthesis of polyfluorinated 6-phenylquinolines and 6,6′-biquinoline has been performed.

Polyfluorinated 4-acetamido- and 4,4′-bis(acetamido)biphenyl were reduced in the Zn–NiCl2–2,2′-bipyridine–aq. DMF system to give their for the first time synthesized less fluorinated analogs containing one or two unsubstituted position ortho to the acetamido group. By involving ortho-unsubstituted 4-acetamido- or 4-aminopolyfluorobiphenyls in the Skraup synthesis, new polyfluorinated 6-phenylquinolines and 6,6′-biquinoline were obtained.

Graphical abstractPolyfluorinated 4-acetamido- and 4,4′-bis(acetamido)biphenyls are reduced in the Zn–NiCl2–2,2′-bipyridine–aq. DMF system to give their ortho-to-NHAc defluorinated analogs which are used as educts in the Skraup synthesis of polyfluorinated 6-phenylquinolines and 6,6′-biquinoline.Figure optionsDownload full-size imageDownload as PowerPoint slide