Copper-Catalyzed Cascade Cyclization of 1,7-Enynes toward Trifluoromethyl-Substituted 1'H-Spiro[azirine-2,4'-quinolin]-2'(3'H)-ones.

A novel method for the synthesis of trifluoromethyl-containing 1'H-spiro[azirine-2,4'-quinolin]-2'(3'H)-ones by a CF3-radical-triggered tandem reaction of benzene-linked 1,7-enynes is described. This protocol utilizes 1-trifluoromethyl-1,2-benziodoxole as the trifluoromethylating reagent and TMSN3 as the aminating reagent. By this method, various potentially bioactive trifluoromethylated 1'H-spiro[azirine-2,4'-quinolin]-2'(3'H)-ones were facilely synthesized via a radical cascade process.