The silver nitrate oxidation of 2,2,4,6,7-pentamethylcoumaran-5-ol

The silver nitrate oxidation of 2,2,4,6,7-pentamethylcoumaran-5-ol () was investigated. The complex mixture of products received is in partial disagreement with the mechanisms supposed so far and proposes a less strong Mills–Nixon effect than assumed until now. Consecutive reactions of 2,2,4,7-tetramethylcoumaran-5,6-dione (), which was received as main product, were examined.