Iodine-promoted insertion of the oxygen atom from water in η4-vinylketene[Fe(CO)3] complexes

Iodine promotes the in situ formation of iron(ii) species from η4-vinylketene[Fe(CO)3] (3a–h) as a key intermediate for the synthesis of 2(5H)-furanones (4a–h) by a sequential water-insertion/carbon–oxygen coupling under mild reaction conditions. Compounds 4a–h were obtained in good to excellent yields. A possible reaction pathway was also proposed by DFT calculations. This methodology can be extended to the synthesis of (5H)-pyrrol-2-ones using anilines, with moderate yields and a few limitations.