Synthesis of 5-deoxypterocarpens, pterocarpens, and coumestans by intramolecular Heck reaction

Two 5-deoxypterocarpens, one pterocarpen, and one coumestan were prepared from deoxychromenes, chromenes, and ortho-iodophenols. The key step in the described synthetic approach is an intramolecular Heck reaction leading to the formation of the C-ring present in the structure of these compounds.