Vol 94, No 3 (2024)

Sequential transformations of molecular complexes and ionic intermediates lead to ionic products of nonionic bromine and alkylacetamides interaction. Molecular geometry, electron structure and thermodynamic parameters were evaluated at ωB97xV/dgdzvp level for all final products and supposed intermediates. A number of intra- and intermolecular noncovalent interactions such as Br···O, C-H···O, C-H···Br, H···O···H and other were revealed with combined use of spectral and computational methods, and defining role of these interactions in products and intermediates stabilization was demonstrated.

A series of new 5-aryl(hetaryl)-4-aroyl-1-isobutyl-3-hydroxy-3-pyrrolin-2-ones were synthesized by reacting methyl esters of aroylpyruvic acids with aromatic (heterocyclic) aldehydes and isobutylamine in dioxane. Antimicrobial activity of the obtained compounds was studied in vitro against Staphylococcus aureus, Escherichia coli and Candida albicans strains.

Diastereomeric oxazolidines were obtained in quantitative yield by boiling levoglucosenone (cyrene) derivative in benzene with ethanolamine. Sterocontrolled synthesis of N-propyl, -butyl, -lauryl aziridines annulated with a pyran ring based on the α-bromoderivative of levoglucosenone and the corresponding amines was carried out under ultrasonic irradiation of the mixture in the presence of an accessible base K₂CO₃ and catalytic amounts 18-crown-6-ether in toluene. The obtained nitrogen-containing heterocycles are promising in terms of structure–activity studies in the synthesized series of compounds.

A method was developed for the synthesis of 11-(2-furyl)-4-hydrazino-8,8-dimethyl-7,10-dihydro-8H-pyrano[3″,4″:5′,6′]pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine on the basis of which new heterocyclic systems were synthesized. The conditions for the azido/tetrazole transformation of the resulting condensed tetrazolo[1,5-c]pyrimidine were studied. Isomeric triazolo[4,3-c]- and -[1,5-c]pyrimidines were synthesized and the conditions for the transformation of the first isomer into the second in accordance with the Dimroth rearrangement were established.

A study was carried out to identify the influence of the size of the cycloalkenyl ring and the nature of the substituent at the nitrogen atom on the structure and stability of the halogen cyclization products N-acyl-N-(2-cyclopent-1-en-1-yl-6-methylphenyl)glycines, which were synthesized from N-acyl-2-(1-cyclopenten-1-yl)-6-methylanilines and methyl bromoacetate followed by alkaline hydrolysis of the resulting methyl glycinates. It was shown that in the reaction of N-benzoyl and N-(4-nitrobenzoyl) derivatives with molecular bromine, 2′-bromo-9-methyl-N-aroyl-1,2-dihydro-3H-spiro[4,1-benzoxazepine-5,1′-cyclopentan]-3-ones and 8-methyl-N-aroyl-3,3a,6,7- tetrahydrobenzo[e]cyclopenta[g][1,4]oxazocin-5(2H)-ones is formed, the ratio of which in the case of the N-benzoyl derivative is ≈1:4, in the case of the N-nitrobenzoyl analogue reaches ≈1:1. Spiro-fused benzoxazepinones, unlike eight-membered heterocycles, are unstable. Samples of these compounds isolated by chromatography decompose with strong darkening within a few hours. In the case of the N-acetyl homologue, the resulting halogenlactonization products cannot be isolated due to their rapid decomposition. The aS*,R*-configuration of the substituents along the N⁷–C⁷^a axis and at C³^a center of chirality of N-aroylbenzoxazocinones was established by X-ray diffraction studies.

The iodomethylation of 2/3-[dimethyl(phenyl)silylmethylthio]-1,3-benzoimidazoles or -1,2,4-triazole with α-iodoketones of the aliphatic and aromatic series in the absence of basic media and solvents leads to formation of unknown salts based on 2/3-mercaptoazolium cations. Reaction of 2-[dimethyl(phenyl)silylmethylthio]-1,3-benzoxazole with α-iodoketones afforded bis(benzoxazol-2-yl)disulfonium derivatives.

Decomposition of alkylammonium tetraarylborates was studied thermogravimetrically. A method was proposed to synthesize triarylboranes by heating the corresponding trimethylammonium tetraarylborates at 140–190°C.

Based on the process of joint reduction of copper and nickel caprylates in benzyl alcohol at 185°C, a simple method for the synthesis of bimetallic copper and nickel nanoparticles was developed. The prepared bimetallic nanoparticles may be of interest for creating new compositions of electrically conductive inks and pastes for 2D and 3D printing. The resulting nanoparticles were characterized by X-ray phase analysis, scanning and transmission electron microscopy in combination with energy-dispersive X-ray spectroscopy. The prepared copper and nickel nanoparticles are single- or two-phase bimetallic solid solutions of various compositions. The effect of the phase composition of bimetallic powders on their resistance to oxidation was studied. It was shown that an increase in the nickel content in the composition leads to a decrease in the degree of nanoparticles oxidation. The proposed method is one-step, does not require the use of additional stabilizers and reducing agents, the synthesis is carried out in one-pot and is easily scalable. The method can also be used to obtain other bi- and polymetallic nanoparticles.