4-dodecylbenzenesulfonic acid (dbsa) has been shown to be an efficient, mild, green, stable and chemoselective brønsted acid catalyst for the synthesis of 1, 1-diacetates (acylals) of aldehydes under solvent-free conditions. the mild condition, eco-friendly, excellent yields, short reaction times and using an easily available, inexpensive and reusable catalyst are important features of this met...

effects of water on the catalytic performances of movtenbo catalyst in the oxidation of propane to acrylic acid have been investigated at different reaction temperatures and different steam contents. obtained results show that both catalytic performances and catalyst structure are very sensitive to the presence of water vapor in the reaction feed. presence of water induces some structural modif...

The unsaturated fatty acid maleinization reaction was adopted according to the well documented procedures of synthesizing the alkenyl succinic anhydrides (ASA) that are often used in industry (i.e. for paper sizing agents and cutting fluids lubricants) . For monounsaturated fatty acid such as oleic acid, 13 times of maleic anhydride to oleic acid molar ratio are recommended to obtain high yield...

kinetic monte carlo simulation was applied to investigation of kinetics and mechanism of oxalic acid degradation by direct and heterogeneous catalytic ozonation. la-containing perovskites including lafeo3, lanio3, lacoo3 and lamno3 was studied as catalyst for oxalic acid ozonation. the reaction kinetic mechanisms of each abovementioned catalytic systems has been achieved. the rate constants val...

the brønsted acidic ionic liquid ([bmim]hso4) catalyzed three-component synthesis of 2h-indazolo[2,1-b]phthalazine-trione derivatives at room temperature. the integrity of the ionic liquid remains reasonably unchanged when it is separated from the reaction mixture by water extraction, as it can be recycled several times without any loss of activity in each of the title syntheses. the products a...

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. ...

the silica aerogel was prepared by the acid–base sol–gel polymerization of tetraethylorthosilicate precursor followed by ambient pressure drying. the prepared silica aerogels were characterized by fourier transform infrared )ft-ir(, thermo-gravimetric and differential thermal analysis )tg/dta(, x-ray diffractometer )xrd(, energy dispersive x-ray microanalysis )edx(, brunauer–emmitt–teller (bet)...

dodecylbenzenesulfonic acid (dbsa) was used as an efficient, cheap and stable brønsted catalyst for acetylation of alcohols and phenols and formylation of alcohols under solvent-free conditions. various primary, secondary and tertiary alcohols were acetylated with acetic anhydride as an acetylating agent under solvent-free conditions in the presence of catalytic amount of dbsa at room temperatu...

In this study, a solid acid was prepared by the sulfonation of surface modified α-zirconium phosphate (ZrP) single-layer nanosheets (SO3H@ZrP), and the prepared solid acid was investigated for the esterification of oleic acid with methanol to produce biodiesel. For comparison, liquid H2SO4 and commercial Amberlyst® 15 catalyst were also evaluated for the same reaction under the same conditions....