MCM-41@Schiff Base-Mn(OAc)₂ Catalyzed Synthesis of Xanthene Derivatives in Water

Abstract

MCM-41@Schiff base-Mn(OAc) 2 , a heterogeneous catalyst, was used for one pot synthesis of xanthene derivatives in water with aldehydes, 5,5-dimethyl-1,3-cyclohexanedione and 2-naphthol. This method exhibited some advantages including excellent yields, environmentally benign and good functional group tolerance, and the catalytic system presented some features of the less amount of catalyst and excellent reusability by experiment.

Synthesis of 14-Substituted-14H-Dibenzo[a,j]Xanthene Derivatives in Presence of Effective Synergetic Catalytic System Bleaching Earth Clay and PEG-600

“…IR spectra were recorded on a Bruker spectrophotometer (Berlin, Germany) using KBr disks and the absorption bands are expressed in cm −1 . 1 H NMR and 13 C NMR spectra were recorded on a Varian as 400 and 300 MHz spectrometer (Palo Alto, CA, USA) in CDCl 3 , chemical shifts (d) are in ppm relative to TMS and coupling constants (J) are expressed in Hertz (Hz). Mass spectra were taken on a Macro mass spectrometer (Waters, MA, USA) by electro-spray method (ES).…”

“…However, these reported methods have many disadvantages, such as harsh reaction conditions, low yields, prolonged reaction times and require the use of excessive quantities of reagents and toxic solvents. To overcome these limitations, the reaction has recently been improved by mixing βnaphthol with aldehydes in the presence of catalysts, such as natural acidic ionic liquid immobilized on magnetic silica [11], task specific dicationic acidic IL [12], MCM-41@Schiff Base-Mn(OAc) 2 in water [13], Amberlyst-15 [14], LiBr [15], sulfamic acid [16], p-TSA [17], I 2 [18], Fe(HSO 4 ) 3 [19], BF 3 •SiO 2 [20], oxalic acid [21], dipyridine cobalt chloride [22], wet cyanuric acid [23], silica-supported perchloric acid [24], Al(HSO 4 ) 2 [25], SelectfluorTM [26], hydrochloric acid or phosphoric acid [27], H 2 SO 4 in acetic acid as solvent [28] and silica sulfuric acid [29]. These methods suffer from one or more disadvantages, such as drastic reaction conditions, long reaction times, a need for special apparatus and the use of hazardous solvents.…”

Lanthanum triflate as a capable catalyst for the synthesis of xanthenediones and the corresponding theoretical studies

“…Xanthenes were made from the Knoevenagel condensation and Michael addition of 1,3-diketones with aromatic aldehydes. In this regards, various catalyst and reagent such as TEBA [9], CsF [10], urea [11], nano zeolites Fe/NaY [12], supercritical diethyl ether [13], natural phosphates [14], taurine [15], acidic ionic liquids [16], CuFe2O4@SiO2-OP2O5H [17], MCM-41@Schiff base-Mn(OAc)2 [18], oleylamine [19], boric acid [20], copper and zinc oxide nanoparticles [21], rGO@Fe3O4@Ni nanocomposite [22], and sulfacetamide organo-catalyst [23] were used to accomplish this transformation. However, many of the mentioned procedures have one or more drawbacks such as: (i) low yields, (ii) long reaction times, (iii) the use of large amount of catalyst, (iv) the use of toxic solvent, and (v) inefficient methods.…”

Acid-catalyzed chemoselective C- and O- prenylation of cyclic 1,3-diketones

“…Owing to its atom-and step-economy, the [3+3] annulation of 1,3-cyclohexanedione with unsaturated precursors represents a more convenient and straightforward strategy. In the presence of acids or water, α,β-unsaturated aldehydes [11][12][13][14][15] and propargylic alcohols [16][17][18][19][20][21] are suitable coupling partners in this process. Despite these advances, exploiting new [3+3] annulation reactions to access 5-chromenone frameworks from other easily accessible and low-cost chemicals is still in high demand.…”