Rapid, efficient and solvent-free synthesis of (un)symmetrical xanthenes catalyzed by recyclable sulfated polyborate
作者:Manisha S. Patil、Amey V. Palav、Chetan K. Khatri、Ganesh U. Chaturbhuj
DOI:10.1016/j.tetlet.2017.06.027
日期:2017.7
straightforward approach to the synthesis of 1,8-dioxo-octahydroxanthenes, 14-phenyl-14H-dibenzo[a,j]xanthene and tetrahydrobenzoxanthene-11-ones under solvent-free conditions usingsulfated polyborate as a highly efficientcatalyst. The procedure offers several advantages including cleaner reaction profile, mild reaction condition, economic, recyclable and environmentally benign catalyst, high yields, simple
Eco-friendly one pot synthesis is developed for 1,8-dioxo-octahydroxanthenes from aldehydes and dimedone using non-toxic, easily prepared and recyclable catalyst (Sm2O3/SiO2) as a silica supported rare earth element under solvent –free conditions. four of the synthesized compounds showed promising ABTS (3i, 68.7; 3b, 59.2; 3h, 50.2 inhibition%) compared with ascorbic acid.