Iridium-catalyzed intramolecular [4 + 2] cycloadditions of alkynyl halides
نویسندگان
چکیده
Iridium-catalyzed intramolecular [4 + 2] cycloadditions of diene-tethered alkynyl halides were investigated by using [IrCl(cod)](2) as catalyst, and dppe was found to be the most suitable phosphine ligand for the reaction. No oxidative insertion of the iridium into the carbon-halide bond was observed, and the reactions proceeded to provide the halogenated cycloadducts in good yield (75-94%). These results are the first examples of cycloadditions of alkynyl halides using an iridium catalyst.
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