Iodocyclization of Ethoxyethyl Ethers to Alkynes: A Broadly Applicable Synthesis of 3-Iodobenzo[<i>b</i>]furans

A wide variety of 3-iodobenzo[<i>b</i>]furans were readily prepared by iodocyclization of 2-alkynyl-1-(1-ethoxyethoxy)benzenes with the I(coll)<sub>2</sub>PF<sub>6</sub>−BF<sub>3</sub>·OEt<sub>2</sub> combination. Aryl-, vinylic-, and alkyl-substituted alkynes undergo iodocyclization in good to excellent yields. The mechanism of the reaction is also discussed.