N-Sulfonic acid poly(4-vinylpyridinium) hydrogen sulfate as an efficient and reusable solid acid catalyst for one-pot synthesis of xanthene derivatives in dry media under ultrasound irradiation

Abstract

N-Sulfonic acid poly(4-vinylpyridinium) hydrogen sulfate catalyzed efficiently the synthesis of xanthene derivatives under ultrasonic irradiation at room temperature, which has prompted various concerns involving cost and environmental persistence. This methodology shows the effect of presence of anion hydrogen sulfate as an important and effective factor on the promotion of the one-pot multi-components and condensation reactions. The catalyst can be recovered by simple filtration and used for several times without a significant loss of catalytic activity.

A convenient, simple and one-pot synthesis of dibenzoxanthenes and tetrahydrobenzoxanthenes by nanotitania-supported sulfonic acid as an efficient and highly reusable nanocatalyst

“…Additionally, its derivatives can be used as dyes, pH-sensitive fluorescent materials in laser technologies and in photodynamic therapy, too [13][14][15][16]. Owing to its wide range of applications, several protocols have been reported in the literatures for its synthesis [17][18][19][20][21][22].…”

Synthesis of Tetrahydrotriazoloacridines: A Synergistic Effect of Microwave Irradiation and Brönsted Acidic Ionic Liquids

“…The performance of the organic reactions by using a green source of energy was one of our goals in the organic synthesis . RTILs can absorb MW irradiation excellently, and this can lead to a rapid temperature increase throughout the reaction system; therefore, it increases reaction rate and yield compared with conventional heating process, and also improves reproducibility.…”

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 our great delight, a significant improvement of the yields was observed when the reaction was conducted in DESs such as ChCl/L-(? )-tartaric acid, ChCl/citric acid, ChCl/oxalic acid (entries [10][11][12][13][14]. Further study showed that the yield could be increased to as high as 93 % when ChCl/itaconic acid was used (Table 1, entry 18).…”

“…Consequently, various well-designed methodologies have been developed to assemble these interesting scaffolds. In particular, the construction of 13-aryl-5H-dibenzo[b,i]xanthene-5,7,12,14-(13H)-tetraones has been conventionally accomplished by reaction of aldehydes with 2-hydroxynaphthalene-1,4-dione in the presence of various catalysts, such as poly(4-vinylpyridinium) hydrogensulfate [9], p-toluenesulfonic acid [10,11], starch sulphate [12], phosphoric acid supported on alumina (H 3 PO 4 /Al 2 O 3 ) [13], N-sulfonic acid poly(4-vinylpyridinium) hydrogensulfate [14], and ionic liquids [15][16][17][18][19][20]. Due to their manifold applications, the development of a novel methodology for synthesis of xanthenes will be a valuable contribution to this class heterocycles.…”