Dibenziodolium and diphenyliodonium triflates display high catalytic activity for the multicomponent reaction that leads to a series of imidazopyridines. Density functional theory (DFT) calculations indicate both salts can play role hybrid hydrogen- halogen-bond-donating organocatalysts, which electrophilically activate carbonyl imine groups during process. The ortho-H atoms in vicinal position I atom dual role: forming additional noncovalent bonds with ligated substrate increasing maximum...

Solvation effects might play the dominant role in catalysis providing an increase or suppression of activity organocatalysts.

This report demonstrates the successful application of electrostatic surface potential distribution analysis for evaluating relative catalytic activity a series azolium-based halogen bond donors. A strong correlation (R2 > 0.97) was observed between positive σ-hole on atom and Gibbs free energy activation model reactions (i.e., abstraction carbonyl activation). The predictive ability applied approach confirmed experimentally. It also determined that donors generally governed by structure...

Kinetic data based on 1 H NMR monitoring and computational studies indicate that in solution, pyrazole-containing iodonium triflates silver(I) triflate bind to each other, such an interplay results the decrease of total catalytic activity mixture these Lewis acids compared separate catalysis Schiff condensation, imine-isocyanide coupling, or nucleophilic attack a triple carbon-carbon bond. Moreover, kinetic cooperation with prevention decomposition salts during reaction progress. XRD study...

Abstract Sulfonium, selenonium, telluronium triflates, as well chloronium, bromonium, and iodonium triflates have been examined in the model Schiff condensation chalcogen‐ halogen bond donating organocatalysts, respectively. The kinetic data indicated that catalytic effect of salt is provided via decrease enthalpy activation reaction, whereas – unexpectedly caused by value entropy activation. In addition, it was experimentally shown activity sulfonium selenonium salts significantly lower...

Chalconium and halonium salts catalyze Schiff condensation. Kinetic data DFT calculations show that the catalytic activity correlates with maximum electrostatic potential on σ-holes, whereas other factors are less significant.

ABSTRACT Halogen bond donors are recognized as electrophilic catalysts in reactions involving carbonyl compounds. This study describes an unexpected inhibition of the Knoevenagel condensation by catalyst. To elucidate intricacies mechanism, overall reaction order and rate constants were determined using 1 H NMR spectroscopy, further experiments with different nucleophiles conducted. The findings revealed that primary is attributed to a substantial acceleration side aldehyde methanolysis,...

Protothecosis is a rare infectious disease caused by non-photosynthetic algae belonging to the genus Prototheca. Its clinical manifestations may be acute or chronic, localized generalized. In humans, protothecosis and, in severe cases, highly lethal disease. manifests as three syndromes: skin soft tissue infection, ulnar bursitis, disseminated including lesions of brain membranes and substance (meningoencephalitis). The diagnosis made on basis histologic examination biopsy material...

Abstract The experimentally obtained kinetic data has indicated the existence of a synergetic cocatalytic effect provided by an iodonium salt in base‐catalyzed Knoevenagel condensation. diphenyliodonium triflate serving as halogen bond‐donating Lewis acid provides higher than zinc(II) or triflic serving, respectively, metal cation‐based and Brønsted acid. Such remains same for broad scope carbonyl compounds covering aldehydes featuring electron‐withdrawing electron‐donating substituents,...

An acyclic diphenyliodonium cation forms stronger interactions with a bulky Lewis base than cyclic dibenziodolium cation.

A four-component one-pot reaction proceeds very rapidly under mild conditions and gives the heterocyclic systems in good yields.

Kinetic data and computational study indicate that in the solution, pyrazole-containing iodolium salts silver(I) center bind each other, such interplay significantly affect total catalytic activity of mixture these Lewis acids compared with separate catalysis reactions required electrophilic activation carbonyl, imino group, or triple CC bond. Moreover, kinetic 1H NMR monitoring cooperation results prevention decomposition organocatalysts by during reaction progress. XRD indicates solid...

Temperature evolution of crystal structure KNO3 embedded into porous glasses with average pore diameters 7 nm, 46 nm and 320 have been studied by neutron X-rays diffraction. For samples it is shown that phase transition temperatures their sequence corresponds to the bulk. sample temperature interval ferroelectric stability enlarges significantly there a range where all three phases coexist. It has demonstrated for becomes stable down 100°K remains after consequent heating-cooling cycles.

Effect of ammonium dihydrogen phosphate admixture on phase transitions in nanostructured solid solutions (1 -x)KH 2 PO 4 -(x)(NH )H at x = 0, 0.05 and 0.15 has been studied by dielectric spectroscopy.The samples have prepared embedding aqueous into porous borosilicate glasses.The X-ray diffraction shown that the crystal structure room temperature corresponds to bulk KDP average nanoparticle diameters are 49 (2) nm for sample with 5 % (NH (ADP) 46 nanocomposites 15 ADP.Dielectric response...