Abstract
The 3,4-dihydrocoumarin derivatives were obtained from 2-alkyl phenols and oxazolones via C-H oxidation and cyclization cascade in the presence of silver oxide (Ag(2)O) and p-toluenesulfonic acid as a Brønsted acid catalyst. This approach provides a one-pot strategy to synthesize the multisubstituted 3,4-dihydrocoumarins with moderate to high yields (64-81%) and excellent diastereoselectivity (>20:1).