Secondary amine based ionic liquid: an efficient catalyst for solvent free one pot synthesis of xanthenes and benzoxanthenes

Abstract

Amine based ionic liquid was reported as an efficient and easily recyclable catalyst for the solvent free environmental benign synthesis of xanthene and benzoxanthene derivatives within 10–30 minutes.

Microwave mediated solvent free synthesis of formazans catalyzed by simple ionic liquids derived from dialkylammonium salts

“…Three different ionic liquids, namely diethylammoniumhydrogensulphate, di-n-propylammoniumhydrogensulphate and di-n-butylammoniumhydrogensulphates were prepared by a reported procedure. 47 Earlier results indicated a decrease in thermal stability according to the sequence 47 Since thermal stability of the ionic liquid did not play a signicant part in the reaction being presently studied, we chose to use [Et 2 NH 2 ]HSO 4 in all the synthesis reported here. A trial reaction was examined using a mixture of 1 : 1 : 1 molar proportion of 4-chloroaniline, benzaldehyde, phenylhydrazine, 1.2 mole of NaNO 2 , 10 mol% of [Et 2 NH 2 ]HSO 4 and 1 mL of deionized water.…”

“…49 Acidic ionic liquids prepared from dialkylamines by a procedure reported earlier. 47 Formazans obtained were conrmed by comparing their melting points with those reported in literature. Melting points were recorded in open capillaries and are uncorrected.…”

“…Preparation of ionic liquids: ionic liquids of dialkylamines [Et 2 NH 2 ]HSO 4 , [(n-propyl) 2 NH 2 ]HSO 4 and [(n-isopropyl) 2 NH 2 ]-HSO 4 were prepared by a procedure describe earlier. 47 General procedure for synthesis of formazan using ionic liquid A mixture of aromatic aldehyde (1 mmol), phenylhydrazine (1 mmol), aromatic amine (1 mmol) and NaNO 2 (1.2 mmol), 10 mol% of [Et 2 NH 2 ]HSO 4 and 1 mL of deionized water was ground to a homogeneous mixture. The bright coloured mixture was exposed to microwave irradiation (240 Watt) for a 1-1.5 min.…”

β-Cyclodextrin as an Efficient and Recyclable Supramolecular Catalyst for the Synthesis of Heterocyclic Compounds

“…Xanthenes and their derivatives have been the subject of considerable interest because of their numerous applications in biological and pharmaceutical research such as antitumor, anticancer, antimicrobial, and antiviral drugs . Besides, these heterocyclic molecules have been widely used as dyes, in pH‐sensitive fluorescent materials, and laser technologies .…”

Zr(HSO4)4: Green, efficient and reusable catalyst for one-pot synthesis of 1,8-dioxooctahydroxanthene under solvent-free conditions

“…Other catalysts such as alum-promoted [26] , potash alum [27] , boric acid [28] , ZrOCl 2 .8H 2 O [29] , nano-Fe 3 O 4 [30] , B(HSO 4 ) 3 [31] , TiO 2 [32] , nano-TiO 2 [33] , BiVO 4 -NPs [34] and InCl 3 [35] and etc. [ [36] , [37] , [38] ].…”