Solvent‐Free Synthesis of 1,8‐Dioxo‐octahydroxanthenes and 14‐Aryl‐14H‐dibenzo[a,j]xanthenes using Saccharin SulfonicAcid as an Efficient and Green Catalyst

Abstract

Saccharin sulfonic acid (SaSA) is utilized as a highly efficient, green and inexpensive sulfonic acid-containing catalyst for the following one-pot multi-component organic transformations: (i) the condensation of dimedone (2 eq.) with aromatic aldehydes (1 eq.) leading to 1,8-dioxo-octahydroxanthenes, and (ii) the reaction of 2-naphthol (2 eq.) with arylaldehydes (1 eq.) leading to 14-aryl-14H-dibenzo[a,j]xanthenes. In these protocols, the title compounds are produced in high to excellent yields and in relatively short reaction times under solvent-free conditions.

Synthesis of 2 H- indazolo[2,1- b ]phthalazine-1,6,11(13 H )-triones using 1,4-disulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium dihydrogen sulfate {DABCO(HSO 3 ) 2 (HSO 4 ) 2 } as a new ionic liquid catalyst

“…In recent years preparation, characterization and use of N-sulfonic acids in organic reactions became an important part of our ongoing research program [18][19][20][21][22][23][24][25][26][27][28][29][30][31], in the continuation of these studies we were interested to investigate the preparation of [DABCO](SO 3 H) 2 (HSO4) 2 and its applicability in the promotion of the organic reactions.…”

12-(2-Hydroxy-6-oxocyclohex-1-enyl)-9,10-dihydro-8H-benzo[a]xanthen-11(12H)-one

“…Reddy et al (2009); Ç elik et al (2009). For the industrial and pharmaceutical significance of xanthenes, see: Zare et al (2012); Menchen et al (2003a,b); Sarma & Baruah, (2005). For ring conformations, see: Cremer & Pople (1975) and for standard bond lengths, see: Allen et al (1987).…”

“…Xanthene derivatives have been used as antibacterial, antiviral, antitumor and anti-inflammatory agents (Zare et al, 2012). These compounds also have applications as dyes in laser technology (Menchen et al, 2003a,b), and as pH sensitive fluorescent materials for the visualization of biomolecules (Sarma & Baruah, 2005).…”

Introduction of a new bi-SO3H ionic liquid based on 2,2′-bipyridine as a novel catalyst for the synthesis of various xanthene derivatives

“…To improve these reactions several methodologies were reported in the literature. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] Although these procedures provide an improvement, most of them suffer from disadvantages such as long reaction times, harsh reaction conditions, need to excess amounts of the reagent, use of organic solvents and use of toxic reagents. Additionally, only some of them are useful for the synthesis of all of the above mentioned xanthenes.…”