Efficient Synthesis of β-Iodobutenolides by Iodolactonization of 2,3-Allenoic Acids with Perfluoroalkyl Iodide as the Iodine Atom Source

A copper-catalyzed iodolactonization of 2,3-allenoic acids for the formation of β-iodobutenolides was reported. The perfluoroalkyl iodide was used as the iodine atom source, which was initially intended to serve as the perfluoroalkylating agent for perfluoroalkylative lactonization of 2,3-allenoic acids. A range of 2,3-allenoic acids can be easily transformed into their corresponding β-iodobutenolides in good yields under mild conditions.