One-pot Green Procedure for Synthesis of Tetrahydrobenzo[a]- xanthene-11-one Catalyzed by Bronsted Ionic Liquids under Solvent-free Conditions

An efficient one-pot condensation of β-naphthol, aldehydes and cyclic 1,3-dicarbonyl compound has been achieved with ionic liquids as catalyst, thus a variety of 8,9,10,12-tetrahydrobenzo[a]xanthen-ll-one derivatives were prepared in good yields. The present approach offers several advantages such as shorter reaction times, good yields and mild reaction conditions.