a green and convenient method for the synthesis of 14-aryl-14h-dibenzo[a,i]xanthene-8,13-diones and spiro[dibenzo[a,i]-xanthene-14,3'-indoline]-2',8,13-triones in the presence of a catalytic amount of cellulose sulfuric acid (csa) as an efficient biopolymer-based catalyst under solvent-free conditions at 100 °c is described. the condensation reactions of β-naphtol, 2-hydroxynaphthalene-1,4-dion...

bifunctional acidic ionic liquids, having both h-imidazolium and -so3h groups as cation moieties (h-bfails) and cf3so3- as anion, were synthesized in high yields. these h-bfails showed significant hydrophilic properties, lower acidity and higher thermal stability relative to common ionic liquids, due to their unique structures. the (propyl or butyl-3-sulfonic) imidazolium trifluoromethane sulfo...

Co@pyr/APTZCMNPs was synthesized, and some of its characteristic analyses, such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were investigated. The results indicated that this heterogeneous catalyst was an excellent and reusable system to synthesize of 14H</e...

In the title compound, C(26)H(28)O(2)S, the dihedral angles between the mean plane of the five membered ring and the 4-(methyl-sulfan-yl)benzyl-idine ring in the two crystallographically independent mol-ecules are 34.05 (10) and 40.53 (15)°. The packing is stabilized by inter-molecular O-H⋯O and C-H⋯O inter-actions.