Pd‐Catalyzed Annulation of β‐Iodovinyl Sulfones with 2‐Halophenols: A General Route for the Synthesis of 3‐Sulfonyl Benzofuran Derivatives

The palladium‐catalyzed annulation between β‐iodovinyl sulfones and 2‐halophenols or 1‐bromo‐2‐naphthol or 2‐bromo‐3‐pyridinol is presented. The annulation process involving oxa‐Michael addition‐elimination and intramolecular Heck reaction leading to form 2,3‐disubstituted benzofurans (aryl benzofuryl sulfones) in good to high yields. The regioselective tandem construction of C−O and C−C bonds has been achieved with a variety of substitution patterns. Moreover, the tandem process is reliable at gram‐scale reactions and a plausible mechanism is also proposed.