We present a new microencapsulated catalyst and report its use in a tandem multicatalyst reaction. Using an encapsulation technique, we developed an active, site-isolated amine catalyst that is capable of catalyzing the addition of nitromethane to an aldehyde. When a second Lewis acid catalyst is added, the nitroalkene intermediate is trapped and converted to the corresponding Michael adduct. W...

Summarization of electronic discussion fora is a unique challenge; techniques that work startlingly well on monolithic documents tend to fare poorly in this informal setting. Additionally, conventional techniques ignore much of the structures that have the potential to serve as valuable features in the summarization task. We present several novel examples of such features, including the catalys...

Fe (III)-catalyzed ozonation yielded better degradation rate and extent of COD (Chemical Oxygen Demand) or oxalic acid as compared with oxidation by ozone alone. Two parameters with strong effects on the efficiency of ozonation are pH of the solution and the catalyst (Fe(3+)) dosage. The existence of a critical pH value determining the catalysis of Fe (III) in acid conditions was observed in ph...

Biodiesel is an alternative fuel for diesel engines consisting of the alkyl monoesters of fatty acids from vegetable oils or animal fats. Most of the biodiesel that is currently made uses soybean oil, methanol, and an alkaline catalyst. The high value of soybean oil as a food product makes production of a cost–effective fuel very challenging. However, there are large amounts of low–cost oils an...

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.

sulfonic acid functionalized sba-15 as a nanoporous acid catalyst was used in the synthesis of 2-aryl benzoxazoles 4 by the condensation of 2-aminophenol 1 and benzoyl chlorides 2 under microwave irradiation in solvent free reaction conditions. the advantages of this methodology are good product yields (60-98%), being environmentally benign, short reaction times and easy work up.

phosphosulfonic acid (psa) was found to be an efficient catalyst for the one-pot three-component hantzsch condensation reaction of arylaldehydes, ethylacetoacetate and ammonium acetate to afford the corresponding 1,4-dihydropyridine and polyhydroquinoline derivatives in high yields. psa was also applied for the one-pot preparation of polyhydroquinolines via four-component reaction of arylaldehy...

one-pot preparation of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles has been conducted in the presence of poly(4-vinylpyridinium butane sulfonic acid) hydrogen sulfate, p(4vpbsa)hso4, as an efficient dual acidic catalyst under solvent-free conditions. reusability of the catalyst, easy work-up procedure, eco-friendly reaction conditions, short reaction times and high yields of th...

A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally fri...

The first efficient and non-precious nanoparticle catalyst for alkene hydrosilylation with commercially relevant tertiary silanes has been developed. The nickel nanoparticle catalyst was prepared in situ from a simple nickel alkoxide precatalyst Ni(O(t) Bu)2 ⋅x KCl. The catalyst exhibits high activity for anti-Markovnikov hydrosilylation of unactivated terminal alkenes and isomerizing hydrosily...