One‐Pot Synthesis of 2‐Substituted Indoles and 7‐Azaindoles <i>via</i> Sequential Alkynylation and Cyclization of 2‐Iodo‐<i>N</i>‐mesylarylamines and Alkynes in the Presence of Cu₂O

A one-pot process was developed to synthesize in moderate to high yield a series of 2-substituted indoles and 7-azaindoles starting from 2-iodo-<i>N</i>-mesylarylamines and terminal alkynes in the presence of Cu₂O in DMF at 90-120 °C. Without isolation of any intermediate, our optimized conditions enabled the introduction of ester, phenyl, hydroxymethyl, hydroxyethyl, <i>N</i>-Boc-aminomethyl, and methyl at the 2-postion of indoles and 7-azaindoles. The reaction tolerates a variety of substrates containing halogens, or acid- or base-sensitive functional groups without requiring a Pd catalyst, a ligand, or a base.