Novel rearrangement of 1,3-benzo(naphtho)dioxin-4(1)-ones under Vilsmeier-Haack reagent

Polyfunctional derivatives of xanthenes and benzoxanthenes in the form of organic perchlorates have been obtained by the interaction of 1,3-benzo(naphtho)dioxin-4(1)-ones with the Vilsmeier-Haack reagent at 110 °C for 5 h. The rearrangement has occurred as an electrophilic triggered recyclization due to the geminal arrangement of oxygen atoms in the six-membered ring as well as the presence of a lactone group in the structure of the starting 1,3-benzo(naphtho)dioxin-4(1)-ones.