Synthesis of Annulated Benzofuran Derivatives from α-(Iodophenyl)-β-oxoesters

ABSTRACT

Reaction of beta-oxoesters with PIFA leads to alpha-(iodophenyl) derivatives. These compounds are the starting point for the preparation of [b] annulated benzofurane derivatives by copper-catalyzed C-O coupling reaction in the presence of K3PO4. Congeners annulated with five-, six-, and seven-membered rings as well as products with tetrahydropyrano-and-pyrido-annulation are prepared. In particular, the cyclopenta[b]benzofurane represents an interesting scaffold with respect to compounds active against SARS-CoV-2. The great potential of the scaffold in a medicinal chemistry context was confirmed by addressing four points of diversification.