A core-shell structured mesoporous silica nanosphere with antagonistic acid and basic sites spatially isolated and designated diffusion path was fabricated and served as an efficient acid-base bifunctional catalyst for one-pot cascade reaction sequences with excellent activity and selectivity.

3,4-Dichloro-5-hydroxy-2(5H)-furanone treated with methyl chloroformate in the presence of diisopropylethylamine (Hünig's base) gave the corresponding carbonate. The labile methoxycarbonyloxy group smoothly undergoes substitution by amino alcohols. The obtained 5-(w-hydroxyalkylamino) mucochloric acid derivatives reacted with peracetylated glucals using triphenylphosphine hydrobromide as a cata...

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. ...

Lactic acid is an important platform molecule in the synthesis of a wide range of chemicals. However, in aqueous solutions without alkali, its efficient preparation via the direct catalysis of sugars is hindered by a side dehydration reaction to 5-hydroxymethylfurfural due to Brønsted acid, which originates from organic acids. Herein, we report that a previously unappreciated combination of com...

Oils with high content of free fatty acid (FFA) can be treated by acid esterification where an alcohol reacts with the given oil in the presence of acid catalyst. The investigated parameters include methanol to oil ratio, temperature and amount of catalyst. The optimum conditions for acid esterification which could reduce FFA content in the feedstock to less than 1.88% (acid value 3.76 mg KOH/g...

 Biodiesel production from non edible oil through transesterification in batch reactor is highly effective technique for kinetic analysis. Temperature, molar ratio, mixing intensity and catalyst influenced the biodiesel production and kinetic. Alkaline catalysts are more efficient in nature as compare to acid and base catalyst. This paper particularly focuses on the impact of NaOH catalyst o...

Asymmetric catalysis is a powerful component of modern synthetic organic chemistry. To further broaden the scope and utility of asymmetric catalysis, new basic concepts for the design of asymmetric catalysts are crucial. Because most chemical reactions involve bond-formation between two substrates or moieties, high enantioselectivity and catalyst activity should be realized if an asymmetric cat...

A new mechanistic approach for the catalytic, enantioselective conjugate addition of nitrogen-based nucleophiles to acceptor-substituted alkenes is reported, which is based on a visible light induced and phosphate base promoted transfer of a single electron from a nitrogen nucleophile to a catalyst-bound acceptor-substituted alkene, followed by a stereocontrolled C-N bond formation through ster...

Introduction Glycerol is the main byproduct of biodiesel production. Nowadays, glycerol surplus is becoming a matter of environmental and economic concern. Therefore, new ideas to convert glycerol in more valuable compounds are needed. Monoglyceride (MG) synthesis by glycerol (Gly) transesterification with fatty acid methyl esters (FAME), Figure 1, is an attractive option to transform this biom...