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Features of Elastomeric Compositions in the Presence of Regenerated Sunflower Oil Production Waste as Filler
(Oles Honchar Dnipro National University, Dnipro, 2015) Sokolova, Lina O.; Ovcharov, Valery I.; Toropin, Mykola V.; Burmistrov, Kostiantyn S.; Tyshchenko, Valeria O.
ENG: The paper investigates the peculiarities of the properties of elastomeric compositions based on butadiene-α-methylstyrene rubber of the Buna KER 1723 brand in the presence of regenerated sunflower oil production waste in comparison with the equal weight content (20.0 phr) of known mineral fillers. It has been shown that the hydrophobized products under study significantly affect the processibility of rubber compounds, the course of sulfur vulcanization at different temperatures, the level of rheokinetic characteristics, and the density of cross-links of elastomeric compositions. It has been established, that in terms of the rubber reinforcement factor, the spent adsorbent with 37 wt.% of the organic component (diatomite P), regenerated by two-stage washing with dichloroethane and petroleum ether, is superior to a product with 57 wt. % organic component (diatomite D), as well as chalk, but inferior to kaolin. Diatomite P can be recommended for use in industrial rubber formulations.
An Efficient Synthetic Route to Substituted Xanthene Analogues
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Varenichenko, S. A.; Kovtun, A.V.; Farat, V. K.; Farat, O. K.
ENG: The reactions of N-[(9-chloro-1,2-dihydrocyclopenta[b]chromen-3-yl)methylene]-Nmethylmethanaminium and N-[(11-chloro-7,8,9,10-tetrahydrocyclohepta[b]chromen-6- yl)methylene]-N-methylmethanaminium perchlorates with (1- phenylethylidene)malononitrile were studied in boiling acetonitrile in the presence of piperidine. These reactions led to the formation of new organic dyes, [(2E)-1-phenyl-3- (9-piperidin-1-yl-1,2-dihydrocyclopenta[b]chromen-3-yl)prop-2-en-1- ylidene]malononitrile and [(2E)-1-phenyl-3-(11-piperidin-1-yl-7,8,9,10- tetrahydrocyclohepta[b]chromen-6-yl)prop-2-en-1-ylidene]malononitrile, obtained in high yields. The structures of the products were confirmed by 1H NMR spectroscopy, mass spectrometry, and elemental analysis. The observed spin-spin coupling constants indicated that the products adopted the E-configurations of the double bonds. The reaction mechanism was determined to proceed via a Knoevenagel condensation followed by nucleophilic substitution of chlorine with a piperidine fragment. Spectroscopic investigations of the dyes were performed in organic solvents, in particular acetonitrile and chloroform. For [(2E)-1-phenyl-3-(9-piperidin-1-yl-1,2-dihydrocyclopenta[b]chromen3-yl)prop-2-en-1-ylidene]malononitrile, the absorption maximum was ~605 nm, and the emission maximum was ~685 nm, with a quantum yield of 34.62% in acetonitrile and 16.84% in chloroform. In contrast, [(2E)-1-phenyl-3-(11-piperidin-1-yl-7,8,9,10- tetrahydrocyclohepta[b]chromen-6-yl)prop-2-en-1-ylidene]malononitrile exhibited an absorption maximum at 607 nm with negligible fluorescence. The synthesized dyes may be of interest to researchers in the field of dye chemistry and related areas.
Synthesis of N-Acyloxy-1-(Dimethoxyphosphoryloxy)Benzimidates from N-Acyloxy-N-Chlorobenzamides
(Oles Honchar Dnipro National University, Dnipro, 2025) Shtamburg, Vasiliy G.; Klots, Evgeniy A.; Shtamburg, Victor V.; Anishchenko, Andrey A.; Shishkina, Svitlana V.; Mazepa, Alexander V.; Kravchenko, Svetlana V.
ENG: Aim. The objective of this research was to investigate the potential interaction between N-acyloxy-N-chlorobenzamides and trialkyl phosphites, along with the characterization of the resulting products' structures. Methods. Employing techniques such as 1H, 31P and 13C NMR spectroscopy, mass spectrometry, and single crystal X-ray diffraction, we have proved that the reaction of N-acyloxy-N-chlorobenzamides with trimethyl phosphite in diethyl ether produces N-acyloxy-1-(dimethoxyphosphoryloxy)benzimidates. Our research demonstrates that the reaction between N-acyloxy-N-chlorobenzamides and trialkyl phosphites offers a novel approach to synthesize Z-N-acyloxy-1-(dialkoxyphosphoryloxy)benzimidates. This discovery unveils a significant chemical transformation of N-acyloxy-N-chlorobenzamides. The structure of N-acyloxy-1-(dimethoxyphosphoryloxy)benzimidates has been confirmed by 1H, 31P and 13C NMR spectroscopy, mass spectrometry, and XRD study. The study of the N-(4-nitrobenzoyloxy)-1-(dimethoxyphosphoryloxy)benzimidate structure has revealed that the N-(4-nitrobenzoyloxy)-1-(dimethoxyphosphoryloxy)benzimidate is the Z-isomer, with the dimethoxyphosphoryloxy moiety and the N-4-nitrobenzoyloxy group being cis-oriented to the N=C double bond. The ether moiety and the N=C double bond are coplanar, while the dimethoxyphosphoryl substituent is orthogonal to the plane of the N=C double bond. The interaction of N-acyloxy-N-chlorobenzamides with trimethyl phosphite has led to a new synthesis of Z-N-acyloxy-1-(dialkoxyphosphoryloxy)benzimidates. The new chemical properties of N-acyloxy-N-chlorobenzamides have been established. The X-ray study of Z-N-4-nitrobenzoyoxy-1-benzimidate has demonstrated the peculiarities of its structure. Notably, an intriguing phenomenon of nitrogen-to-oxygen migration of the dimethoxyphosphoryl group has been observed.
Synthesis of N,N'-(((Hydrazine-1,2- Dicarbonothioyl)Bis(Azanediyl))Bis(2,2,2-Trichloroethane-1,1- Diyl)) Carboxamides and Their Cyclisation Into N,N'-(((1,3,4-Thiadiazole-2,5- Diyl)Bis(Azanediyl))Bis(2,2,2-Trichloroethane-1,1-Diyl))Carboxamides
(Oles Honchar Dnipro National University, Dnipro, 2025) Pavlova, Valeriia V.; Zadorozhnii, Pavlo V.; Kiselev, Vadym V.; Romanenko, Pavlo V.; Okhtina, Oxana V.; Kharchenko, Aleksandr V.
ENG: 1,3,4-Thiadiazole derivatives are widely used in science and technology as biologically active compounds, components of polymer and rubber compositions, dyes and varnishes, catalysts, as well as materials for microelectronics and nanotechnology. This work presents the synthesis of new bis-amidoalkylated derivatives of 2,5-diamino-1,3,4-thiadiazole. The preparation of these compounds is based on the reaction of oxidative dehydrosulfonation of N,N'-(((hydrazine-1,2-dicarbonothioyl)bis(azanediyl))bis(2,2,2-trichloroethane-1,1- diyl))carboxamides using a mixture of iodine and triethylamine in DMF. The reaction was carried out at room temperature for two hours. This method yields target products in the range of 63–92 %. The advantage of the method is the absence of the need for expensive or hard-to-find reagents. NMR ¹H and ¹³C spectroscopy confirmed the structure of the synthesized compounds. The 1H NMR spectra of synthesized 1,3,4-thiadiazoles are distinguished by the presence of doublet signals corresponding to two NH protons observed in the 9.53–6.69 ppm range, along with a doublet of doublets assigned to the CH proton of the alkylamide fragment appearing at 6.77– 6.69 ppm. The 13C NMR spectra exhibit characteristic resonances of the C=O carbon at 168.8–164.7 ppm and the C=N carbon of the thiadiazole ring at 158.9–158.6 ppm. Furthermore, characteristics signals attributed to the CCl3_ moiety and the CH carbon of the alkylamide fragment are observed at 101.5–101.2 and 70.0–69.4 ppm respectively.
Interaction of Labile N-Alkoxy-N-Chloro-N’-Arylureas and N-Acetoxy-Nalkoxyureas With Trimethyl Phosphite
(Oles Honchar Dnipro National University, Dnipro, 2025) Shtamburg, Vasiliy G.; Klots, Evgeniy A.; Anishchenko, Andrey A.; Shtamburg, Victor V.; Shishkina, Svitlana V.; Mazepa, Alexander V.; Kravchenko, Svetlana V.
ENG: The freshly synthesized N-alkoxy-N-chloro-N’-4-bromophenylureas undergo reaction with trimethyl phosphite in diethyl ether at room temperature yielding respectively dimethyl N-alkoxy-N-(N’-4- bromophenylcarbamoyl)phosphoroamidates with high yields. The unstable N-alkoxy-N-chloro-N’-phenylureas, freshly synthesized at -30°C, interact with trimethyl phosphite in diethyl ether at this low temperature to produce previously unknown dimethyl N-alkoxy-N-(N’-phenylcarbamoyl)phosphoroamidates. This reaction is the first example of the nucleofilic substitution at the nitrogen atom for unstable N-alkoxy-N-chloro-N’-phenylureas. Careful conditions selection and precise control made it possible to pevent premature destruction of the starting N-alkoxyN-chloro-N’-4-bromophenylureas and N-alkoxy-N-chloro-N’-phenylureas. In contrast, N-acetoxy-N-alkoxyureas do not react with trimethyl phosphite under the same conditions. The structures of the resulting dimethyl N-alkoxy-N- (N’-4-bromophenylcarbamoyl)phosphoroamidates and dimethyl N-alkoxy-N-(N’- phenylcarbamoyl)phosphoroamidates were confirmed by ¹H, ³¹P, and ¹³C NMR spectroscopy, as well as mass spectrometry. A comparative analysis of ¹H, ³¹P and ¹³C NMR spectra of these dimethyl N-alkoxy-N-(N’- arylcarbamoyl)phosphoroamidates with those of dialkyl N-alkoxy-N-(N’-4- nitrophenylcarbamoyl)phosphoroamidates revealed numerous shared features and general structural characteristics of N-alkoxy-N-(N’-arylcarbamoyl)phosphoroamidates
New Hybrid Xanthene-Pyrylium Dyes: Synthesis and Spectral Properties
(Oles Honchar Dnipro National University, Dnipro, 2025) Varenichenko, Svetlana A.; Smetanin, Nikolay V.; Farat, Oleg K.
ENG: In this work we studied the interaction of N'-(4-formyl-2,3-dihydro-1H-xanthen-9-yl)-N,N-dimethylimidoformamide with 2,6-di-tert-butyl-4-methylpyrylium perchlorate and 2-methyl-4,6-diphenylpyrylium tetrafluoroborate in acetic anhydride under various conditions. Thus, when carrying out the reaction with 2,6-di-tert-butyl-4-methylpyrylium perchlorate at 100 °C for 6 h, the corresponding dye is formed with the amidine group replaced by acetyl. In the case of carrying out the reaction with 2-methyl-4,6-diphenylpyrylium tetrafluoroborate at room temperature for 1 h, the dye is formed with the amidine fragment preserved. The absorption spectra of the obtained dyes were recorded in various solvents and the extinction coefficients were calculated. The absorption maximum of 4-{(E)-2-[9- (acetylamino)-2,3-dihydro-1H-xanthen-4-yl]vinyl}-2,6-di-tert-butylpyrylium perchlorate in toluene and chloroform is approximately 675 nm, whereas in water it is hypsochromically shifted to 605 nm. The absorption coefficient of this dye in chloroform is observed to be the highest, with a value that is 5-7 times higher than that in water or toluene. A modification in the polarity of the solvent exerts minimal influence on the absorption maximum of 2-[(E)-2-(9- {[(1E)-(dimethylamino)methylene]amino}-2,3-dihydro-1H-xanthen-4-yl)vinyl]-4,6-diphenylpyrylium tetrafluoroborate, which is situated at approximately 715 nm.
Interaction of N-Alkoxy-N-Chloro-N’-Arylureas With Trialkyl Phosphites AS a Route to Dialkyl N-Alkoxy-N-(N’’- Arylcarbamoyl) Phosphoramidates. Synthesis
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Shtamburg, Vasiliy G.; Klots, Evgeniy A.; Anishchenko, Andrey A.; Shishkina, Svitlana V.; Mazepa, Alexander V.; Kravchenko S. V.
ENG: This article is dedicated to the study of the interaction of some kinds of N-alkoxy-Nchloroureas, such as N-alkoxy-N-chloro-N’-(4-nitrophenyl)ureas, N-ethoxy-N-chloroN’-(2-nitrophenyl)urea, N-methoxy-N-chloro-N’-(4-chlorophenyl)urea, and N-alkoxyN-chloro-N’-alkylureas, with trialkyl phosphites. The stable N-alkoxy-N-chloro-N’-(4- nitrophenyl)ureas interact with trialkyl phosphites in diethyl ether at room temperature with preferential formation of dialkyl N-alkoxy-N-(N’-4- nitrophenylcarbamoyl)phosphoramidates. N-Ethoxy-N-chloro-N’-(2-nitrophenyl)urea reacts with trimethyl phosphite in diethyl ether at room temperature giving dimethyl Nethoxy-N-(N’-2-nitrophenylcarbamoyl)phosphoramidate. The interaction of unstable Nmethoxy-N-chloro-N’-(4-chlorophenyl)urea with trialkyl phosphites in diethyl ether gives dialkyl N-methoxy-N-(N’-4-chlorophenylcarbamoyl)phosphoramidates with good yields. N-Alkoxy-N-chloro-N’-alkylureas react with trimethyl phosphite under the same conditions with selective formation of dimethyl N-alkoxy-N-(N’-alkylcarbamoyl)phosphoramidates with excellent yields. In all these cases, the nucleophilic substitution at the nitrogen atom is accompanied by a further Michaelis-Arbuzov rearrangement. The original method of creating molecules containing a P–N bond is proposed. The structures of dialkyl Nalkoxy-N-(N’-arylcarbamoyl)phosphoramidates and dimethyl N-alkoxy-N-(N’- alkylcarbamoyl)phosphoramidates have been confirmed by 1H, 31P, and 13C NMR spectroscopy, and mass spectrometry. The synthesized dialkyl N-alkoxy-N-(N’- arylcarbamoyl)phosphoramidates and dimethyl N-alkoxy-N-(N’- arylcarbamoyl)phosphoramidates simultaneously possess structural features of both phosphoramidates and ureas, and may be regarded as potential biologically active substances.
Dialkyl-N-Alkoxy-N-(4-Toluenesulfonyl) Phosphoramidates: Synthesis and Structure
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Shtamburg Vasiliy G.; Klots E. A.; Shtamburg V. V.; Anishchenko A. A.; Shishkina S. V.; Kravchenko S. V.; Mazepa A. V.
ENG: This study investigates the reaction between N-alkoxy-N-chloro-4-toluenesulfonamides and N-chloro-N-(methoxy)methanesulfonamide with trialkyl phosphites, resulting in the formation of dialkyl N-alkoxy-N-(4-toluenesulfonyl)phosphoroamidates and dialkyl N-methoxy-N-methanesulfonylphosphoroamidates, respectively. The resulting dialkyl Nalkoxy-N-(4-toluenesulfonyl)phosphoramidates and N-alkoxy-Nmethanesulfonylphosphoramidates are identified as products of nucleophilic substitution at the amide nitrogen atom. The structures of these compounds have been confirmed by H, P and C NMR spectroscopy, mass spectrometry, and an XRD study. The XRD study of dimethyl N-methoxy-N-(4-toluenesulfonyl)phosphoroamidate and dimethyl N-ethoxy-N-(4-toluenesulfonyl)-phosphoroamidate reveals a pyramidal configuration at the amide nitrogen atom, along with the shortening of the N–O(Alk) bond and the elongation of the N–P and N–S bonds. In the asymmetric part of the unit cell, dimethyl N-ethoxy-N-(4-toluenesulfonyl)phosphoramidate exists in the form of two independent molecules that differ in the degree of pyramidality of the nitrogen atom and the lengths of its bonds.