SelectfluorTM Promoted Synthesis of 9-Aryl-1,8-dioxooctahydroxanthane Derivatives under Solvent-Free Conditions

A novel and efficient procedure for the synthesis of 1,8-dioxo-octahydro-xanthenes through one-pot condensation of 5,5-dimethyl-1,3-cyclohexadione with aryl aldehydes in the presence of selectfluorTM [1-(chloromethyl)-4-fluoro-1,4-diazoniabicyclo[2,2,2]octane bis(tetrafluoroborate) as catalyst under solvent free conditions was applied. It demonstrated several advantages such as good yields of products, simple operation, convenient separation, and inexpensive catalyst.