Fe-Catalyzed Radical Trifluoromethyl-Alkenylation of Alkenes or Alkynes with 2-Amino-1,4-naphthoquinones
Lin Tang1, Fang Yang1, Shuai Zhang2
1College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang, Henan 464000, China.
Abstract:
The first Fe-catalyzed three-component radical trifluoromethyl-alkenylation of alkenes with 2-amino-1,4-naphthoquinones and CF3SO2Na is reported. The developed reaction enables the highly regioselective preparation of a variety of valuable CF3-substituted 1,4-naphthoquinones in acceptable yields. In the light of the catalytic system, alkynes smoothly afford the corresponding three- or four-component trifluoromethyl-alkenylation products. This protocol features use of easily available and inexpensive reagents, broad substrate scope, and simple reaction conditions.
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