2H-1-Benzopyrans (2H-chromenes) and 3,4-dihydro-2H-1-benzopyrans (chromanes) are important classes of oxygenated heterocyclic compounds 1 that have attracted much synthetic interest because of the biological activity 2. and 3. of naturally occurring representatives. In the course of our work on the synthesis of therapeutically valuable compounds with antioxidizing properties, we needed to access chromanes bearing various 2-oxoalkyl groups at the C-2 ...
