Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H) as a new nanoporous acid catalyst was used in the one-pot synthesis of polyhydroquinolines derivatives via the Hantzsch four component condensation reaction of aldehydes, b-ketoesters, dimedone and ammonium acetate under solvent free conditions with short reaction time in excellent yields. SBA-P...

Effective solid acid catalysts play a key role to produce high-quality biodiesel through triglyceride transesterification. The present work describes a facile technique for the synthesis of a high-performing sulfonated multi-walled carbon nanotube (S-MWCNTs) solid acid catalyst for fatty acid ethyl ester (biodiesel) production. The results indicated that S-MWCNTs possessed high acidity due to t...

In this article, simple, convenient synthesis of 2-aryl-1- arylmethyl-1H-1,3-benzimidazole (1,2-disubstituted benzimidazoles) via condensation of 1,2-phenylenediamine and aromatic aldehydes using SBA-Pr-SO3H as a nanoporous solid acid catalyst in green protocol was reported.

The one-pot, multi-component synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) by tandem Knoevenagel-Michael reaction of phenylhydrazine, ethyl acetoacetate and aldehydes in the presence of silica-bonded N-propylpiperazine sulfamic acid (SBPPSA) as a recyclable solid acid catalyst was reported. SBPPSA showed much the same efficiency when used in consecutive reaction runs.

Silica tungstic acid (STA) has been found to be an efficient and reusable solid acid catalyst for the synthesis of 2-amino-4H-chromenes via the three-component reaction of aromatic aldehydes, malononitrile, and β-naphthol. STA as a novel solid acid was characterized by X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy.

Silica-bonded N-propyldiethylenetriamine sulfamic acid (SPDTSA) is employed as a recyclable heterogeneous solid acid catalyst for the synthesis of benzopyrano[2,3-d]pyrimidines  through one-pot condensation reaction of salicylaldehydes, malononitrile and secondary amines  at room temperature under solvent-free conditions. SPDTSA showed much the same efficiency when used in con...

The one-pot, multi-component synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) by tandem Knoevenagel-Michael reaction of phenylhydrazine, ethyl acetoacetate and aldehydes in the presence of silica-bonded N-propylpiperazine sulfamic acid (SBPPSA) as a recyclable solid acid catalyst was reported. SBPPSA showed much the same efficiency when used in consecutive reaction runs.

nano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and solvents.  this nano-sized sulfated titania has been prepared by a sol-gel hydrothermal process. the prepared sulfated titania s...

A new and efficient synthesis of benzoxanthene drivatives from the three-component condensation reaction ofaryl aldehydes and β-naphthol under solvent-free conditions in the presence of β-cyclodextrin sulfonic acid, as an efficient heterogeneous solid acid catalyst with excellent yields and short reaction time is presented

3,4-ِDihydropyrano[c]chromene derivatives were synthesized using sulfonic acid functionalized silica (SiO2-Pr-SO3H) as a highly efficient heterogenous solid acid catalyst via one-pot three-component condensation of aromatic aldehydes with malononitrile and 4-hydroxycoumarin in excellent yields.