Glycine-promoted rapid synthesis of novel xanthene derivatives in ionic liquid

Abstract

A green route for the synthesis of multi-substituted 2,3-dihydro-xanthenone derivatives using ionic liquid as solvent and amino acid as promoter is described. The reaction is simple and proceeds well at room temperature and devoid of the use of any harmful catalyst or solvent. This is an efficient technique.Key words: xanthene, ionic liquid, glycine, room temperature.

[Bmim]PF6: An efficient tool for the synthesis of diverse bioactive heterocycles

“…[94][95][96] Another efficient protocol was developed for the synthesis of 2,3-dihydro-1Hxanthen-1-one derivatives (61) via the cycloaddition of 1,3-cyclohexanediones (37b or 37b′) and salicylaldehyde (44) using glycine as promoter in [bmim]PF 6 at 25 °C (Scheme 23). 98 Conventional solvents, such as acetonitrile, DMF, DMSO, etc., were also screened for this reaction but lower yields were attained. Under the optimized conditions, other amino acids, such as L-histidine, L-lysine, L-alanine, as catalyst produced lower yields.…”

Organocatalytic Reactions Under Unusual Conditions

“…Kidwai et al tested different amino acids as catalysts at aldol reactions leading to xanthene derivatives [94]. From the amino acid tested, histidine, lysine, alanine and glycine, the last one was the best catalyst (Scheme 25).…”

ZnO nanostructures: a heterogeneous catalyst for the synthesis of benzoxanthene and pyranopyrazole scaffolds via a multi-component reaction strategy

“…8 Numerous methods have been reported for the synthesis of benzoxanthene derivatives, which include trontiumtriflate, 9 silicasulphuricacid, 10 P 2 O 5 and indium(III) chloride, 11,12 methane sulfonic acid, 13 NaHSO 4 -SiO 2 , 14 pdodecylbenzenesulfonic acid (DBSA), 15,16 tetrabutylammoniumhydrogensulphate (TBAHS). 17 imidazolium based ionic liquid [bmim]PF 6 , 18 and trimethylsilyl chloride (TMSCL). 19 Pyranopyrazole derivatives are a significant class of biologically active heterocycles.…”