The aqueous Diels-Alder reaction of 1,3-cyclohexadiene with 1,4-benzoquinone was compared and contrasted to the same reaction catalyzed with Flextyl P, a novel Ti(IV) performance catalyst. The catalyst improved conversion by 22% versus the uncatalyzed reaction and represents a rare example of a Ti(IV) catalyzed Diels-Alder reaction in water.

alkali and alkaline earth metals hydrogen sulfate catalyzed the one-pot three component condensation reactions of aldehydes, 1,3-dicarbonyl compounds and urea or thiourea under solvent-free conditions leading to 3,4-dihydropyrimidin-2(1h)-ones in high yields at 80 °c. our results showed that biginelli reaction not only is ph dependent, but the cation of catalyst plays an important role.

nicotine-based ionic liquid has been used as a green catalyst for pyridine-catalyzed huisgen reaction. it promoted addition of dimethylacetylenedicarboxylate to aldehydes or n-tosyl imines leading to efficient synthesis of 2-benzoylfumarates and 1-azadienes respectively under pyridine free odorless ionic liquid conditions. the improved results were obtained in terms of enhanced yields, with min...

A new and imaginative technique for the synthesis of substituted pyranoquinoline via Algar Flyn Oyamanda oxidation cyclization approach has been achieved by hydrogen peroxide and sodium hydroxide catalyzed of quinoline chalcone with intramolecular cyclization to formed pyranoquinoline. In this reaction, two new C-C bonds were formed in a one step with high atom economy. The possible reaction pa...

The mutarotation of N-acetylneuraminic acid (Neu5Ac) proceeds by four kinetically distinct pathways: (i) the acid-catalyzed reaction of neutral Neu5Ac; (ii) the spontaneous reaction of the carboxylic acid (the kinetically equivalent acid-catalyzed reaction on the anion being ruled out by the solvent deuterium kinetic isotope effect of 3.74 ± 0.68); (iii) a spontaneous, water-catalyzed, reaction...

reaction between aromatic aldehydes and 3–methyl-1-phenyl-2-pyrazoline-5-one catalyzed by nano-sio2/hclo4 in water under reflux provided a simple and efficient route for the synthesis of 4-((5-hydroxy-3-methyl-1-phenyl-1h-pyrazol-4-yl)(aryl)methyl)-3-methyl-1-phenyl-1h-pyrazol-5-ol derivatives in high yields.

Reaction between aromatic aldehydes and 3–methyl-1-phenyl-2-pyrazoline-5-one catalyzed by nano-SiO2/HClO4 in water under reflux provided a simple and efficient route for the synthesis of 4-((5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)(aryl)methyl)-3-methyl-1-phenyl-1H-pyrazol-5-ol derivatives in high yields.

Through kinetic analysis, we demonstrate that the formation of catalyst and substrate reservoirs plays a crucial role in titanium(III)-catalyzed ketone-nitrile coupling reaction. Together with insight from previous studies, model is assembled reflects observed influence ZnCl2 Et3N byproducts as well hydrochloride additive, which employed frequently titanium(III) catalysis. We further propose fo...

Herein, we describe the creation of an artificial protein cage housing a dual-metal-tagged guest that catalyzes linear, two-step sequential cascade reaction. The consists fusion HaloTag and monomeric rhizavidin. Inside capsid, established ruthenium-catalyzed allylcarbamate deprotection reaction followed by gold-catalyzed ring-closing hydroamination led to indoles phenanthridines with overall yi...

Reaction 2 is catalyzed by the enzyme imidazoleacetol phosphate transaminase (1). Reaction 3 is catalyzed by the enzyme L-histidinol phosphate phosphatase (2). Reaction 4 is catalyzed by the enzyme L-histidinol dehydrogenase (3, 4). This report is concerned with the purification and description of the enzyme from N. crassa catalyzing Reaction 1, the dehydration of D-erythroimidazoleglycerol pho...