Fluoroboric Acid Adsorbed on Silica-Gel–Catalyzed Synthesis of 14-Aryl-14H-dibenzo[a,j]xanthene Derivatives

Choline chloride and itaconic acid-based deep eutectic solvent as an efficient and reusable medium for the preparation of 13-aryl-5H-dibenzo[b,i]xanthene-5,7,12,14(13H)-tetraones

“…To further expand the potential of this approach as a tool for the construction of xanthenes, we investigated the reaction of benzaldehyde with b-naphthol (4) or dimedone (5). As shown in Scheme 4, benzaldehyde could react smoothly with b-naphthol or dimedone to give the desired 14-phenyl-14H-dibenzo[a,j]xanthene (6) [27] and 3,3,6,6-tetramethyl-9-phenyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione (7) [47] in high yields.…”

Application of highly sulfonated single-walled carbon nanotubes: An efficient heterogeneous catalyst for the one-pot synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes under solvent-free conditions

“…Therefore, the synthesis of this class of heterocyclic compounds is practically important. Various catalysts such as Bro ¨nsted acids [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], Lewis acids [24][25][26][27][28][29][30][31][32][33], molecular iodine [34], nano-AgI [35], heteropolyacid [36,37], ionic liquids [38][39][40][41], nano-ZnO [42] and resin [43] have been developed for the synthesis of dibenzoxanthenes. However, several of these methodologies involve long reaction times, harsh conditions, use of toxic organic solvents, excess amount of catalyst, non-reusable catalysts, and tedious work-up confine the usefulness of some reported methodologies.…”