A silica supported sulfuric acid catalyzed [3+2] cycloaddition of nitriles and sodium azide to form 5-substituted 1H-tetrazoles is described. The protocol can provide a series of 5-substituted 1H-tetrazoles using silica sulfuric acid from nitriles and sodium azide in DMF in 72%-95% yield.

silica sulfuric acid is employed as solid acid catalyst for the clean and less hazardousprotection of carbonyl compounds as 2,4-dinitrophenylhydrazone under solvent-free conditions.

silica sulfuric acid as an efficient and reusable heterogeneous catalyst has been used for the preparation of amidines 2 from formimidate 1 by reaction with aromatic amines at room temperature in good to excellent yields. imidate was prepared by treatment of equimolar quantities of triethyl orthoformate and diaminomaleonitrile in refluxing dioxane. all the compounds were characterized fully by ...

the aryl-(z)-n-[2-amino-1,2-dicyanovinyl]formamidine 2 cyclize in solvent-free conditions and in the presence of a base to give a 5-amino-1-aryl-4-cyanoimidazoles 3. silica sulfuric acid as an efficient and reusable heterogeneous catalyst has been used for the preparation of amidines 2 from formimidate 1 through reaction with aromatic amines at room temperature and in good to excellent yields. ...

a mild and green method has been developed for the preparation of coumarins derivatives through the one-pot reactions. in our study,various phenols and ethyl acetoacetate compound in which we used silica-supported boron sulfonic acid [sio2/b(so4h)3] as a new, highly efficient and tri-functional inorganic brønsted acid catalyst were processed under solvent-free condition and thermal. the catalys...

Silica sulfuric acid is employed as solid acid catalyst for the clean and less hazardousprotection of carbonyl compounds as 2,4-dinitrophenylhydrazone under solvent-free conditions.

Five types of nanofillers, namely, silica, surface-silylated silica, alumina, surface-silylated alumina, and boron nitride, were tested in this study. Nanocomposites composed of an epoxy/amine resin and one of the five types of nanoparticles were tested as dielectrics with a focus on (i) the surface functionalization of the nanoparticles and (ii) the water absorption by the materials. The dispe...

Five types of nanofillers, namely, silica, surface-silylated silica, alumina, surface-silylated alumina, and boron nitride, were tested in this study. Nanocomposites composed of an epoxy/amine resin and one of the five types of nanoparticles were tested as dielectrics with a focus on (i) the surface functionalization of the nanoparticles and (ii) the water absorption by the materials. The dispe...

We have investigated the electrochemical oxidation of sulfuric acid on boron-doped synthetic diamond electrodes (BDD) obtained by HF CVD on p-Si. The results have shown that high current efficiency for sulfuric acid oxidation to peroxodisulfuric acid can be achieved in concentrated H2SO4 ( /2 M) at moderate temperatures (8 /10 8C). The main side reaction is oxygen evolution. Small amounts of pe...