By pyrolysis of metal compounds supported on aerosil together with 1,2-diaminobenzene, the materials containing nanoparticles of Ni, Cu, or iron oxides, along with a carbon component, have been obtained. The rate of the water-gas shift reaction over nickel-iron-containing catalyst at temperatures >450°C is close to the rate observed over bulk Fe3O4, with a 5-fold lower metal content. In the low-temperature region (≤400°C), copper-containing system is found to be the most active catalyst among those studied.
The development of efficient oxygen evolution electrocatalysts is key to advancing water electrolysis. Molecular and hybrid iron-containing catalysts as an accessible alternative to platinum group metal systems are analyzed in the review. Achievements in complex design are summarized with an emphasis on structure–activity relationships, redox behavior, and ligand architecture. Particular attention is paid to the stability of molecular systems and approaches to their heterogenization on conductive supports. A comparative analysis of electrochemical parameters has allowed the most efficient classes of complexes to be identified and the principles of their development to be defined. Key challenges and directions for creating robust and inexpensive iron-based anodic electrocatalysts are outlined.
The catalytic efficiency of carbene palladium complexes LPdCl2, including PEPPSI-type compounds L(Py)PdCl2, in the Sonogashira reaction of aryl halides with terminal alkynes has been established. It is shown that sterically shielded carbene complexes provide almost quantitative product yields (up to 99
Polypropylene’s usage in delicate technical applications are restricted due to its high flammability, low oxygen index, high heat release rate, and melting and dripping during combustion. The ignition, thermal deterioration, and combustion behaviour of polypropylene are all thoroughly covered in this review. Resent flame-retardant techniques for polypropylene, such as intumescent systems, halogen-free additives based on phosphorus and nitrogen, nanofillers, and hybrid synergistic systems that promote char formation and decrease heat release, are given special attention. Recent advancements in environmentally friendly flame-retardant technologies, such as bio-based retardants, reactive additives, nano-structured barriers, etc. are highlighted.
A two-stage synthesis of N-substituted aminomethylcyclopentanols has been carried out via the oxidative hydroxyhalogenation of individual methylcyclopentene isomers using a H2O2 + Hal mixture (Hal = Cl, Br), leading to the formation of the corresponding hydroxychloro(bromo) derivatives, followed by substitution of the halogen atom with an amino group in an alkaline medium. Optimal conditions for the conjugated hydroxyhalogenation reaction have been determined, and it is shown that the reaction proceeds through the formation of an intermediate species containing an electrophilic halogen atom. The selectivity of the halogen substitution reaction in hydroxyhalogenides depends on temperature and pH of the medium. Depending on the medium pH, products of aminolysis are corresponding amino alcohols either epoxides via dehydrohalogenation process.
