Al2 (SO4)3.18H2O as an Efficient and Environmentally Benign Natural Catalyst for Facile and Solvent-free Synthesis of Xanthene Derivatives

An environmentally friendly, facile and solvent-free synthetic route for aluminum sulfateoctadecahydrate (al2(so4)3.18h2o) catalyzed one-pot multi-component synthesis of 12-aryltetrahydrobenzo[α]xanthene-11-ones, 1,8-dioxo-octahydroxanthenes and 14-aryl-14hdibenzo[α,j]xanthenes has been developed. the readily, easy to handle, non-toxic, environmentalfriendly and low-cost catalyst, easily separated with no column chromatographic separation, shortreaction times and high to excellent yields is an option for the economical, mild and facile synthesisof these rings.