Palladium-Catalyzed Intramolecular Migratory Cycloisomerization of 3-Phenoxy Acrylic Acid Ester via C-O Bond Cleavage and C-O/C-C Bonds Formation for 2,3-Disubstituted Benzofurans Synthesis

Migratory cycloisomerization using transition metal catalyst is useful for synthesizing substituted het-erocyclic compounds. We achieved palladium-catalyzed migratory cycloisomerization of 3-o-alkynylphenoxy acrylic acid ester derivatives to give 2,3-disubstituted benzofurans. Although there are several reports of benzofuran synthesis with palladium-catalyzed migratory cycloisomerization, migratory groups are limited to allyl and propargyl groups. This report is the first example of benzofuran synthesis with palladium -cata-lyzed cycloisomerization of C(sp(2))-O bond cleavage.

Automated summary

Migratory cycloisomerization using transition metal catalyst is a useful method for synthesizing substituted heterocyclic compounds. In this study, we achieved palladium-catalyzed migratory cycloisomerization of 3-o-alkynylphenoxy acrylic acid ester derivatives to obtain 2,3-disubstituted benzofurans. This is the first report of benzofuran synthesis with palladium-catalyzed cycloisomerization of C(sp(2))-O bond cleavage, expanding the scope of migratory groups for this reaction.