Clean Synthesis of 14-Alkyl and 14-Aryl-14-H-dibenzo[a,j]xanthenes

Two clean and efficient methods for the synthesis of 14-alkyl and 14-aryl-14-H-dibenzo[a,j] xanthenes are described: (1) in aqueous media, using p-dodecylbenezetiesulfonic acid (DBSA) as the catalyst (20 mol%), under heat conditions. (2) Under solvent-free condition, using p-toluene sulfonic acid (p-TSA) as catalyst and in microwave irradiation.