Pub Date : 2023-04-28DOI: 10.33609/2708-129x.89.03.2023.55-69
Leon Shteinberg
Catalysis with phosphorus P(III) compounds (phosphorus trichloride and phosphorous acid) in the acylation of aniline with 3=hydroxy=2=naphthoic acid in various media (toluene, octane, chlorobenzene, para=xylene, ortho=xylene, ortho=chlorotoluene, mesitylene, pseudocumene, n.=deсan, ortho= dichlorobenzene, mixtures of ortho=xylene with nitrobenzene) upon boiling and vigorous distillation of water leads to the formation of 3=hydroxy=2=naphthoic acid anilide. With an increase in the reaction temperature in the range from 111 (toluene) to 170 °C (pseudo cumene), a monotonous increase in the initial rate of formation of the target product is observed. In this case, the temperature dependence of the logarithm of the velocity obeys the Arrhenius equation, and the activation energy Ea is 66.2 kJ/mol. Higher-boiling n.=decane (175 °С) and ortho=dichlorobenzene (180 °С) fall out of this dependence, in which the initial rate of formation of anilide 3=hydroxy=2=naphthoic acid, compared with that for pseudocumene (170 °С), decreases. The latter may be due to the decomposition or oxidation of the catalyst at such a high temperature with the transition of P(III) to P(V), which does not have catalytic activity. The interaction of aniline with 3=hydroxyl=2=naphthoic acid proceeds as a series of sequential and parallel reactions in which, in addition to 3=hydroxyl=2= naphthoic acid anilide, 3=aniline=2=naphthoic acid and its anilide are formed as impurities. The most acceptable solvents are ortho=xylene and ortho=chlorotoluene with boiling points of 146 and 156°C, in which the yield of the target product is up to 98%. Below 146 °C the reaction proceeds at a relatively low rate; above 156°C the amount of impurities increases significantly, mainly in parallel with an increase in the reaction temperature, and the maximum yield of 3=hydroxyl=2=naphthoic acid anilide decreases. This requires its additional purification, significantly complicating the technological process. The addition of 10–20% by volume of nitrobenzene to ortho=xylene leads to an increase in the yield of 3=oxy=2=naphthoic acid anilide by 1.25–1.42 times in the temperature range of 146–148°C with increasing solvent polarity (ε), respectively, from 2.3 to 7.64. This may be due to an increase in the quantity of the monomers of the catalyst and/or 3=oxy=2=naphthoic acid and aniline in reaction mass and the speed of water separation.
{"title":"SYNTHESIS OF 3-HYDROXY-2-NAPHTHOIC ACID ANILIDE CATALYZED BY PHOSPHORUS (III) COMPOUNDS IN VARIOUS MEDIA","authors":"Leon Shteinberg","doi":"10.33609/2708-129x.89.03.2023.55-69","DOIUrl":"https://doi.org/10.33609/2708-129x.89.03.2023.55-69","url":null,"abstract":"Catalysis with phosphorus P(III) compounds (phosphorus trichloride and phosphorous acid) in the acylation of aniline with 3=hydroxy=2=naphthoic acid in various media (toluene, octane, chlorobenzene, para=xylene, ortho=xylene, ortho=chlorotoluene, mesitylene, pseudocumene, n.=deсan, ortho= dichlorobenzene, mixtures of ortho=xylene with nitrobenzene) upon boiling and vigorous distillation of water leads to the formation of 3=hydroxy=2=naphthoic acid anilide. With an increase in the reaction temperature in the range from 111 (toluene) to 170 °C (pseudo cumene), a monotonous increase in the initial rate of formation of the target product is observed. In this case, the temperature dependence of the logarithm of the velocity obeys the Arrhenius equation, and the activation energy Ea is 66.2 kJ/mol. \u0000Higher-boiling n.=decane (175 °С) and ortho=dichlorobenzene (180 °С) fall out of this dependence, in which the initial rate of formation of anilide 3=hydroxy=2=naphthoic acid, compared with that for pseudocumene (170 °С), decreases. The latter may be due to the decomposition or oxidation of the catalyst at such a high temperature with the transition of P(III) to P(V), which does not have catalytic activity. \u0000The interaction of aniline with 3=hydroxyl=2=naphthoic acid proceeds as a series of sequential and parallel reactions in which, in addition to 3=hydroxyl=2= naphthoic acid anilide, 3=aniline=2=naphthoic acid and its anilide are formed as impurities. \u0000The most acceptable solvents are ortho=xylene and ortho=chlorotoluene with boiling points of 146 and 156°C, in which the yield of the target product is up to 98%. Below 146 °C the reaction proceeds at a relatively low rate; above 156°C the amount of impurities increases significantly, mainly in parallel with an increase in the reaction temperature, and the maximum yield of 3=hydroxyl=2=naphthoic acid anilide decreases. This requires its additional purification, significantly complicating the technological process. \u0000The addition of 10–20% by volume of nitrobenzene to ortho=xylene leads to an increase in the yield of 3=oxy=2=naphthoic acid anilide by 1.25–1.42 times in the temperature range of 146–148°C with increasing solvent polarity (ε), respectively, from 2.3 to 7.64. This may be due to an increase in the quantity of the monomers of the catalyst and/or 3=oxy=2=naphthoic acid and aniline in reaction mass and the speed of water separation.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84105494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-24DOI: 10.33609/2708-129x.89.02.2023.91-99
R. Panteleimonov, K. Pershina, Ivan Shcherbatiuk
The possibility of formation of an active interphase on iron particles in C/PVDF has been dictated by the thermochemical reactions of iron and iron oxides in the presence of carbon. The composition with polyvinylidene fluoride (PVDF) changed the redox activity of iron particles and decreased pure iron (Fe0) amount by 0,24 wt. %. The surface properties of various compositions have been characterized by scanning electron microscopy with the analytical mode for determining the relationship between the microstructure and local thermal reactions on the iron particle surface. A relationship between the surface composition, morphology and electrochemical behavior of the Fe/C/PVDF electrodes has been found. Electric current affects the surface morphology and changes it from a mosaic structure to a monolith in atmosphere oxygen. The electrochemical properties of Fe/C/PVDF electrodes have been tested using cyclic voltammetry (CVA). The long air contact (for more than 3 hours) during electrochemical cycling changes the surface structure in the direction of decreasing crystallinity. The Fe/C/PVDF electrode can be charge in neutral solutions (pH ~7).
{"title":"FORMATION OF ACTIVE INTERPHASE ON THE IRON PARTICLES IN C/PVDF ELECTROCHEMICAL SYSTEMS","authors":"R. Panteleimonov, K. Pershina, Ivan Shcherbatiuk","doi":"10.33609/2708-129x.89.02.2023.91-99","DOIUrl":"https://doi.org/10.33609/2708-129x.89.02.2023.91-99","url":null,"abstract":"The possibility of formation of an active interphase on iron particles in C/PVDF has been dictated by the thermochemical reactions of iron and iron oxides in the presence of carbon. The composition with polyvinylidene fluoride (PVDF) changed the redox activity of iron particles and decreased pure iron (Fe0) amount by 0,24 wt. %. The surface properties of various compositions have been characterized by scanning electron microscopy with the analytical mode for determining the relationship between the microstructure and local thermal reactions on the iron particle surface. A relationship between the surface composition, morphology and electrochemical behavior of the Fe/C/PVDF electrodes has been found. Electric current affects the surface morphology and changes it from a mosaic structure to a monolith in atmosphere oxygen. The electrochemical properties of Fe/C/PVDF electrodes have been tested using cyclic voltammetry (CVA). The long air contact (for more than 3 hours) during electrochemical cycling changes the surface structure in the direction of decreasing crystallinity. The Fe/C/PVDF electrode can be charge in neutral solutions (pH ~7).","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89317741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-24DOI: 10.33609/2708-129x.89.02.2023.100-108
V. Chernii, I. Tretyakova, N. Fedosova, I. Denisenko, Yan Dovbii, V. Kovalska
Usually in order to obtain out-of-plane substituted phthalocyanine complexes of zirconium and hafnium (PcML2), the reaction of substitution of chlorine atoms in dichloridophthalocyaninates PcMCl2 is used. However, this method has some limitations because during this reaction, hydrogen chloride is released, which can initiate the hydrolysis of starting compounds sensitive to an acidic environment, in particular, β-ketoesters, which, in turn, can lead to the formation of by-products and, accordingly, to a decrease purity and yield of target complexes. At the same time, in similar reactions in which the initial phthalocyanine compounds are dihydroxyphthalocyaninates of zirconium and hafnium (PcM(OH)2), as a result of interaction with dicarbonyl compounds or carboxylic acids, water is formed, which does not have a negative effect on the starting substances or on the course of the reaction as a whole. Methods of obtaining zirconium and hafnium dihydroxyphthalocyaninates based on metal alkoxides and by hydrolysis of the corresponding PcMCl2 were investigated in the work. It was established that the synthesis of PcM(OH)2 based on the corresponding alkoxides occurs with low yields (25–40%), increasing the reaction temperature from 140 to 220oC does not lead to their significant increase. It was found that the hydrolysis of PcMCl2 should be carried out under more stringent conditions than previously described, which makes it possible to obtain PcM(OH)2 with high yields. The reactivity of PcM(OH)2 was investigated when interacting with β-diketones and aliphatic carboxylic acids and compared with the reactivity of PcMCl2. It was established that the reactivity of PcM(OH)2 is similar to PcMCl2. However, it should be noted that in the case of the synthesis of β-ketoesterphthalocyanine complexes, the use of the corresponding PcM(OH)2 leads to a significant increase in the yield of the final products of the reaction compared to PcMCl2. This effect can be explained by the fact that hydrogen chloride is not released during the reaction with PcM(OH)2 and, accordingly, hydrolysis of the ester group does not occur.
{"title":"ZIRCONIUM AND HAFNIUM DIHYDROXYPHTHALOCYANINATES: METHODS OF SYNTHESIS AND REACTIVITY","authors":"V. Chernii, I. Tretyakova, N. Fedosova, I. Denisenko, Yan Dovbii, V. Kovalska","doi":"10.33609/2708-129x.89.02.2023.100-108","DOIUrl":"https://doi.org/10.33609/2708-129x.89.02.2023.100-108","url":null,"abstract":"Usually in order to obtain out-of-plane substituted phthalocyanine complexes of zirconium and hafnium (PcML2), the reaction of substitution of chlorine atoms in dichloridophthalocyaninates PcMCl2 is used. However, this method has some limitations because during this reaction, hydrogen chloride is released, which can initiate the hydrolysis of starting compounds sensitive to an acidic environment, in particular, β-ketoesters, which, in turn, can lead to the formation of by-products and, accordingly, to a decrease purity and yield of target complexes. At the same time, in similar reactions in which the initial phthalocyanine compounds are dihydroxyphthalocyaninates of zirconium and hafnium (PcM(OH)2), as a result of interaction with dicarbonyl compounds or carboxylic acids, water is formed, which does not have a negative effect on the starting substances or on the course of the reaction as a whole. Methods of obtaining zirconium and hafnium dihydroxyphthalocyaninates based on metal alkoxides and by hydrolysis of the corresponding PcMCl2 were investigated in the work. It was established that the synthesis of PcM(OH)2 based on the corresponding alkoxides occurs with low yields (25–40%), increasing the reaction temperature from 140 to 220oC does not lead to their significant increase. It was found that the hydrolysis of PcMCl2 should be carried out under more stringent conditions than previously described, which makes it possible to obtain PcM(OH)2 with high yields. \u0000The reactivity of PcM(OH)2 was investigated when interacting with β-diketones and aliphatic carboxylic acids and compared with the reactivity of PcMCl2. It was established that the reactivity of PcM(OH)2 is similar to PcMCl2. However, it should be noted that in the case of the synthesis of β-ketoesterphthalocyanine complexes, the use of the corresponding PcM(OH)2 leads to a significant increase in the yield of the final products of the reaction compared to PcMCl2. This effect can be explained by the fact that hydrogen chloride is not released during the reaction with PcM(OH)2 and, accordingly, hydrolysis of the ester group does not occur.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85189064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-24DOI: 10.33609/2708-129x.89.02.2023.109-124
I. Sharanov, Y. Slominskii
Recently, a large number of studies have been dedicated to chemistry and physical studies of polymethine dyes, especially to the functionalized symmetrical heptamethinecyanines based on the indole derivatives. Due to their unique and versatile spectral properties, which lie in the near infrared region (NIR), meso-substituted indotricarbocyanine dyes are widely used in various physical and biological fields. In the present work, we have developed methods of synthesis of a series of indotricarbocyanine dyes with di- and trimethylene bridging groups in the γ,γ'-positions and donor substituents in the meso-position of the polymethine chromophore and studied their effects on the spectral properties of the dyes. The obtained data indicated that the change of the substituent in the meso-position of the chromophore and the presence of a polymethylene bridging groups allow to vary significantly the absorption maxima of the synthesized indoheptamethinecyanine dyes without altering the length of the polymethine chain. It was shown that the electron-donating nitrogen-containing substituents lead, according to the Forster-Dewar-Knott rule, to a hypsochromic shifts of the absorption maxima. However, it was found that the methoxy group in the meso-position of the polymethine chromophore in some cases exhibited unexpected "acceptor" properties due to a certain steric hindrance, resulting in a red shift of the absorption band, in contrast to the other donor substituents. Additionally, the effects of the insertion of di- and trimethylene bridging groups to the polymethine chain of the cyanine dyes on their spectral properties were studied. The synthesized meso-substituted indotricarbocyanines demonstrated significant solvatochromism and spectral properties that lie in the red and near-infrared regions.
{"title":"SYNTHESIS AND ABSORPTION SPECTRA OF INDOTRICARBOCYANINE DYES WITH ELECTRON-DONATING GROUPS IN THE MESO-POSITION OF THE POLYMETHINE CHAIN","authors":"I. Sharanov, Y. Slominskii","doi":"10.33609/2708-129x.89.02.2023.109-124","DOIUrl":"https://doi.org/10.33609/2708-129x.89.02.2023.109-124","url":null,"abstract":"Recently, a large number of studies have been dedicated to chemistry and physical studies of polymethine dyes, especially to the functionalized symmetrical heptamethinecyanines based on the indole derivatives. Due to their unique and versatile spectral properties, which lie in the near infrared region (NIR), meso-substituted indotricarbocyanine dyes are widely used in various physical and biological fields. In the present work, we have developed methods of synthesis of a series of indotricarbocyanine dyes with di- and trimethylene bridging groups in the γ,γ'-positions and donor substituents in the meso-position of the polymethine chromophore and studied their effects on the spectral properties of the dyes. The obtained data indicated that the change of the substituent in the meso-position of the chromophore and the presence of a polymethylene bridging groups allow to vary significantly the absorption maxima of the synthesized indoheptamethinecyanine dyes without altering the length of the polymethine chain. It was shown that the electron-donating nitrogen-containing substituents lead, according to the Forster-Dewar-Knott rule, to a hypsochromic shifts of the absorption maxima. However, it was found that the methoxy group in the meso-position of the polymethine chromophore in some cases exhibited unexpected \"acceptor\" properties due to a certain steric hindrance, resulting in a red shift of the absorption band, in contrast to the other donor substituents. Additionally, the effects of the insertion of di- and trimethylene bridging groups to the polymethine chain of the cyanine dyes on their spectral properties were studied. The synthesized meso-substituted indotricarbocyanines demonstrated significant solvatochromism and spectral properties that lie in the red and near-infrared regions.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76498564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-24DOI: 10.33609/2708-129x.89.02.2023.71-82
V. Pekhnyo, A. Omel’chuk, L. Koval
The article is dedicated to the 150th anniversary of the birth of V.O. Plotnikov is an academician of the Academy of Sciences of Ukraine, a chemist widely known to the scientific community, especially in the field of electrochemistry of non-aqueous solutions, the founder of the world-famous Kyiv School of Electrochemistry, which was formed in the 20s of the last century. The article presents the facts of Plotnikov's biography, in particular his studies, the period of his formation as an electrochemist scientist; theoretical and applied research results achieved by him and his followers, which relate to the most progressive for that time provisions on electrolytic dissociation, the chemical theory of solutions and the chemistry of complex compounds.
{"title":"To the 150th anniversary of the birth academician Volodymyr Oleksandrovich PLOTNIKOV","authors":"V. Pekhnyo, A. Omel’chuk, L. Koval","doi":"10.33609/2708-129x.89.02.2023.71-82","DOIUrl":"https://doi.org/10.33609/2708-129x.89.02.2023.71-82","url":null,"abstract":"The article is dedicated to the 150th anniversary of the birth of V.O. Plotnikov is an academician of the Academy of Sciences of Ukraine, a chemist widely known to the scientific community, especially in the field of electrochemistry of non-aqueous solutions, the founder of the world-famous Kyiv School of Electrochemistry, which was formed in the 20s of the last century. The article presents the facts of Plotnikov's biography, in particular his studies, the period of his formation as an electrochemist scientist; theoretical and applied research results achieved by him and his followers, which relate to the most progressive for that time provisions on electrolytic dissociation, the chemical theory of solutions and the chemistry of complex compounds.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89882014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-24DOI: 10.33609/2708-129x.89.02.2023.83-90
V. Smilyk, Sergii Fomaniyk, G. Kolbasov, Igor Rysetskiy, Michael Danilov
Cu2O-Cu3VO4 films were obtained by electrochemical synthesis. The analysis of polarization curves and Pourbaix diagrams for copper and vanadium ions made it possible to analyze the possible reactions that occur during the deposition of films. At potentials from 0 to -0.2V, mainly monovalent copper oxide Cu2O with Cu3VO4 impurities precipitated in the working solution. At the same time, there are two competing processes of acidification of the near-electrode layer as a result Cu2O formation reaction and alkalinization as a result of the chemical interaction of Cu2O with HVO42-. The formation of an excess of OH- ions can inhibit the reaction rate of the formation of Cu3VO4, accelerating the reaction of the formation of Cu2O. Thus, deposition of Cu3VO4 will take place to a lesser extent compared to Cu2O. Accordingly, to increase the yield of Cu3VO4, an attempt was made to reduce the deposition current, which, according to literature, helps to reduce the effect of the pH change near the electrode layer. Where, as known the critical current limit at change pH starts from 5 or more mA/cm2. For the synthesis of the films, a current of up to 1 mA/cm2 selected, which contributed to the production of the Cu3VO4 - Cu2O composite, as was established further from the analysis of X-ray patterns. It is shown that their photoelectrochemical properties depend on the heat treatment conditions. This is expressed by the difference in the spectral characteristics of the quantum yield and the value of the photocurrent in the samples annealed in air and argon. Using the X-ray phase analysis method, it was established that heat treatment in argon contributes to the formation of a Cu3VO4 and Cu2O composite, in contrast to heat treatment in air, where a mixture of CuO and V2O5 oxides is mainly formed. In the film annealed in air due to impact of wide-band oxide compounds, a smaller value of the quantum yield of the photoelectrochemical current and a narrower spectral dependence were observed. The stretching of the spectrum into the region of visible light on the spectral curves of the photocurrent quantum yield is caused by the contribution of copper vanadate with Eg = 1.5 eV. Analysis of photocurrent quantum output spectra and X-ray patterns showed that an increase in monovalent copper in the film structure contributes to the growth of photocurrent in the wavelength range of 450-600nm at a potential of -0.2 relative. h.s.e in 2 times. This indicates a positive effect of heat treatment in argon on increasing the efficiency of photocathodes based on a composite of Cu3VO4 and Cu2O for photoelectrochemical cells.
{"title":"SYNTHESIS AND PHOTOELECTROCHEMICAL PROPERTIES OF SU2O-CU3VO4 COMPOSITE FILMS","authors":"V. Smilyk, Sergii Fomaniyk, G. Kolbasov, Igor Rysetskiy, Michael Danilov","doi":"10.33609/2708-129x.89.02.2023.83-90","DOIUrl":"https://doi.org/10.33609/2708-129x.89.02.2023.83-90","url":null,"abstract":"Cu2O-Cu3VO4 films were obtained by electrochemical synthesis. The analysis of polarization curves and Pourbaix diagrams for copper and vanadium ions made it possible to analyze the possible reactions that occur during the deposition of films. At potentials from 0 to -0.2V, mainly monovalent copper oxide Cu2O with Cu3VO4 impurities precipitated in the working solution. At the same time, there are two competing processes of acidification of the near-electrode layer as a result Cu2O formation reaction and alkalinization as a result of the chemical interaction of Cu2O with HVO42-. The formation of an excess of OH- ions can inhibit the reaction rate of the formation of Cu3VO4, accelerating the reaction of the formation of Cu2O. Thus, deposition of Cu3VO4 will take place to a lesser extent compared to Cu2O. Accordingly, to increase the yield of Cu3VO4, an attempt was made to reduce the deposition current, which, according to literature, helps to reduce the effect of the pH change near the electrode layer. Where, as known the critical current limit at change pH starts from 5 or more mA/cm2. For the synthesis of the films, a current of up to 1 mA/cm2 selected, which contributed to the production of the Cu3VO4 - Cu2O composite, as was established further from the analysis of X-ray patterns. It is shown that their photoelectrochemical properties depend on the heat treatment conditions. This is expressed by the difference in the spectral characteristics of the quantum yield and the value of the photocurrent in the samples annealed in air and argon. Using the X-ray phase analysis method, it was established that heat treatment in argon contributes to the formation of a Cu3VO4 and Cu2O composite, in contrast to heat treatment in air, where a mixture of CuO and V2O5 oxides is mainly formed. In the film annealed in air due to impact of wide-band oxide compounds, a smaller value of the quantum yield of the photoelectrochemical current and a narrower spectral dependence were observed. The stretching of the spectrum into the region of visible light on the spectral curves of the photocurrent quantum yield is caused by the contribution of copper vanadate with Eg = 1.5 eV. Analysis of photocurrent quantum output spectra and X-ray patterns showed that an increase in monovalent copper in the film structure contributes to the growth of photocurrent in the wavelength range of 450-600nm at a potential of -0.2 relative. h.s.e in 2 times. This indicates a positive effect of heat treatment in argon on increasing the efficiency of photocathodes based on a composite of Cu3VO4 and Cu2O for photoelectrochemical cells.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85227847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-24DOI: 10.33609/2708-129x.89.01.2023.34-45
Yu. S. Yapontseva, V. Kublanovsky, T. Maltseva
The chemical composition, current efficiency and some properties of galvanic binary CoMo and CoW alloys, deposited from both alkaline citrate and citrate-pyrophosphate electrolytes, were studied. It is shown that the main difference between mono- and polyligand electrolytes is the mechanism of the electrodeposition process and the rate of passage of limiting stages preceding the formation of an electrochemically active complex. During electrolysis in a citrate solution, the limiting step is the mass transfer of [CoCit2]4– complexes, while in the citrate-pyrophosphate one, the process proceeds with kinetic control, and the hydrodynamic regime does not significantly affect the content of metals and the rate of their deposition. The use of a polyligand electrolyte makes it possible to increase the current efficiency for CoW alloys from 32.1 to 45.5% in the convective mass transfer mode and from 5.9 to 35.7% in the diffusion transfer mode. During electrodeposition from citrate-pyrophosphate electrolytes of the same composition of alloys of two different refractory metals, it was found that the current efficiency of the CoMo alloy is on average 20% higher than that of CoW. It has been found that at a close value of the content of the refractory component in X-ray amorphous alloys, the differences in the magnetic and corrosion properties of the coatings are determined by the nature of the refractory metal. Thus, during electrodeposition from a polyligand electrolyte, CoMo alloys have Ms 300–380 emu·cm-3 and Hc 60–72 Oe, while CoW alloys have Ms 22–45 emu·cm-3 and Hc 50–70 Oe. Both types of alloys are characterized by Mr/Ms – 0.2-0.3. The properties of CoW alloys deposited from a monoligand citrate electrolyte approach hard magnetic materials with Mr/Ms – 0.6–0.7.
{"title":"COMPARISON OF THE PROPERTIES OF CoW AND CoMo ALLOYS DEPOSITED BOTH FROM ALKALINE CITRATE AND CITRATE-PYROPHOSPHATE ELECTROLYTES","authors":"Yu. S. Yapontseva, V. Kublanovsky, T. Maltseva","doi":"10.33609/2708-129x.89.01.2023.34-45","DOIUrl":"https://doi.org/10.33609/2708-129x.89.01.2023.34-45","url":null,"abstract":"The chemical composition, current efficiency and some properties of galvanic binary CoMo and CoW alloys, deposited from both alkaline citrate and citrate-pyrophosphate electrolytes, were studied. It is shown that the main difference between mono- and polyligand electrolytes is the mechanism of the electrodeposition process and the rate of passage of limiting stages preceding the formation of an electrochemically active complex. During electrolysis in a citrate solution, the limiting step is the mass transfer of [CoCit2]4– complexes, while in the citrate-pyrophosphate one, the process proceeds with kinetic control, and the hydrodynamic regime does not significantly affect the content of metals and the rate of their deposition. The use of a polyligand electrolyte makes it possible to increase the current efficiency for CoW alloys from 32.1 to 45.5% in the convective mass transfer mode and from 5.9 to 35.7% in the diffusion transfer mode. During electrodeposition from citrate-pyrophosphate electrolytes of the same composition of alloys of two different refractory metals, it was found that the current efficiency of the CoMo alloy is on average 20% higher than that of CoW. It has been found that at a close value of the content of the refractory component in X-ray amorphous alloys, the differences in the magnetic and corrosion properties of the coatings are determined by the nature of the refractory metal. Thus, during electrodeposition from a polyligand electrolyte, CoMo alloys have Ms 300–380 emu·cm-3 and Hc 60–72 Oe, while CoW alloys have Ms 22–45 emu·cm-3 and Hc 50–70 Oe. Both types of alloys are characterized by Mr/Ms – 0.2-0.3. The properties of CoW alloys deposited from a monoligand citrate electrolyte approach hard magnetic materials with Mr/Ms – 0.6–0.7.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78891356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-24DOI: 10.33609/2708-129x.89.01.2023.18-33
N. Roik, L. Belyakova
Mesoporous silicas of MCM‑41 type with surface silanol, 3-aminopropyl, and β‑cyclodextrin‑containing groups were prepared by hydrothermal‑assisted base‑catalyzed sol‑gel condensation of structure-forming silanes in the presence of micelles of long‑chain quaternary ammonium salt. Characterization of synthesized silica materials was realized by low‑temperature nitrogen adsorption‑desorption and chemical analysis of surface layer. It was found that addition of ‑cyclodextrin‑containing silane into the sol‑gel reaction mixture causes formation of MCM‑41‑type organosilica with higher surface area and hexagonally arranged uniform mesoporous structure. Sorption ability of synthesized silica materials towards sodium cholate and sodium taurocholate was studied in dependence of solution pH and concentration. It was found that sorption increases due to chemical immobilization of oligosaccharide moieties in the surface layer of silica, and achieves maximal values in the pH regions of molecular forms of bile acids prevailing. Experimental sorption results were analyzed using Freundlich, Redlich - Peterson, and Brunauer - Emmett - Teller models. The formation of island-type structures of bile salts with β‑cyclodextrin-containing surface sorption centers due to cooperative interactions between sorbate moieties was proved.
{"title":"PERIODIC MESOPOROUS ORGANOSILICAS WITH CHEMICALLY IMMOBILIZED β CYCLODEXTRIN MOIETIES FOR BILE SALTS SORPTION","authors":"N. Roik, L. Belyakova","doi":"10.33609/2708-129x.89.01.2023.18-33","DOIUrl":"https://doi.org/10.33609/2708-129x.89.01.2023.18-33","url":null,"abstract":"Mesoporous silicas of MCM‑41 type with surface silanol, 3-aminopropyl, and β‑cyclodextrin‑containing groups were prepared by hydrothermal‑assisted base‑catalyzed sol‑gel condensation of structure-forming silanes in the presence of micelles of long‑chain quaternary ammonium salt. Characterization of synthesized silica materials was realized by low‑temperature nitrogen adsorption‑desorption and chemical analysis of surface layer. It was found that addition of ‑cyclodextrin‑containing silane into the sol‑gel reaction mixture causes formation of MCM‑41‑type organosilica with higher surface area and hexagonally arranged uniform mesoporous structure. Sorption ability of synthesized silica materials towards sodium cholate and sodium taurocholate was studied in dependence of solution pH and concentration. It was found that sorption increases due to chemical immobilization of oligosaccharide moieties in the surface layer of silica, and achieves maximal values in the pH regions of molecular forms of bile acids prevailing. Experimental sorption results were analyzed using Freundlich, Redlich - Peterson, and Brunauer - Emmett - Teller models. The formation of island-type structures of bile salts with β‑cyclodextrin-containing surface sorption centers due to cooperative interactions between sorbate moieties was proved.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75914976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-24DOI: 10.33609/2708-129x.89.01.2023.60-67
A. Yavolovskii, Araksia Davtian, L. Grishchuk, Sergei Pluzhnik-Glagyr, I. Rakipov, Yu. E. Ivanov, Dmytro Chikhichin, G. Kamalov
A Derivatives of 2-thiouracil are characterized by wide spectrum of biological activity, which is characteristic of most representatives this heterocycles class. In particular, 2-(2-oxo-2-phenylethylthio)-pyrimidin-4(3H)-ones belong to the group of non-nucleoside inhibitors of HIV-1 reverse transcriptase. The antimalarial properties of 2-(2-oxo-2-phenylethylthio)-4-R-pyrimidine derivatives, which proved to be effective inhibitors of CIpP protease of Plasmodium falciparum, are being studied. Known examples of 2-(2-oxo-2-phenylethylthio)-pyrimidines modification at the "4" position of the heterocycle are limited to use 4-chloro derivatives, which, in turn, are formed according to the classical method by reaction of pyrimidine-4(3H)-ones with POCl3 at boiling point of reaction mixture. In this work, we present an alternative version of modification the above-mentioned class of compounds. By amination amide function of 6-R-2-(2-oxo-2-arylethylthio)-pyrimidin-4(3H)-ones derivatives of with ethanolamine and 1-aminopropane-2,3-diol using sulfonate method, synthesized and characterized new compounds a 6-R-2-(2-oxo-2-phenylethylthio)-pyrimidines series by spectral methods. The advantages of this scheme are discussed (the formation of intermediate sulfonates and the amination stage do not require harsh conditions and are carried out with satisfactory yields). The proposed scheme can be recommended in cases where the original substrate contains functional groups that are labile at high temperatures and sensitive to an acidic environment.
A 2-硫脲嘧啶衍生物具有广谱的生物活性，这是这类杂环化合物中大多数代表的特征。特别是2-(2-氧-2-苯基乙基硫)-嘧啶-丁-4(3H)- 1属于HIV-1逆转录酶的非核苷类抑制剂。2-(2-氧-2-苯基乙基硫)-4- r -嘧啶衍生物被证明是恶性疟原虫CIpP蛋白酶的有效抑制剂，其抗疟特性正在研究中。已知的2-(2-氧-2-苯基乙基硫代)-嘧啶在杂环“4”位置的修饰例子仅限于使用4-氯衍生物，而这些衍生物又根据经典方法由嘧啶-4(3H)- 1与POCl3在反应混合物的沸点下反应形成。在这项工作中，我们提出了一个替代版本的修饰上述类别的化合物。以6-R-2-(2-氧-2-芳基乙基硫)-嘧啶-4(3H)- 1衍生物与乙醇胺和1-氨基丙炔-2,3-二醇为原料，用磺酸盐法合成了6-R-2-(2-氧-2-苯基乙基硫)-嘧啶系列化合物，并用光谱方法对其进行了表征。讨论了该方案的优点(中间磺酸盐的形成和胺化阶段不需要苛刻的条件，并且产率令人满意)。在原始底物含有在高温下不稳定且对酸性环境敏感的官能团的情况下，建议采用该方案。
{"title":"AMINATION OF 2-(2-OXO-2-ARYLETHYLTHIO)-PYRIMIDIN-4(3H)-ONE DERIVATIVES USING THE SULFONATE METHOD","authors":"A. Yavolovskii, Araksia Davtian, L. Grishchuk, Sergei Pluzhnik-Glagyr, I. Rakipov, Yu. E. Ivanov, Dmytro Chikhichin, G. Kamalov","doi":"10.33609/2708-129x.89.01.2023.60-67","DOIUrl":"https://doi.org/10.33609/2708-129x.89.01.2023.60-67","url":null,"abstract":"A Derivatives of 2-thiouracil are characterized by wide spectrum of biological activity, which is characteristic of most representatives this heterocycles class. In particular, 2-(2-oxo-2-phenylethylthio)-pyrimidin-4(3H)-ones belong to the group of non-nucleoside inhibitors of HIV-1 reverse transcriptase. The antimalarial properties of 2-(2-oxo-2-phenylethylthio)-4-R-pyrimidine derivatives, which proved to be effective inhibitors of CIpP protease of Plasmodium falciparum, are being studied. Known examples of 2-(2-oxo-2-phenylethylthio)-pyrimidines modification at the \"4\" position of the heterocycle are limited to use 4-chloro derivatives, which, in turn, are formed according to the classical method by reaction of pyrimidine-4(3H)-ones with POCl3 at boiling point of reaction mixture. In this work, we present an alternative version of modification the above-mentioned class of compounds. By amination amide function of 6-R-2-(2-oxo-2-arylethylthio)-pyrimidin-4(3H)-ones derivatives of with ethanolamine and 1-aminopropane-2,3-diol using sulfonate method, synthesized and characterized new compounds a 6-R-2-(2-oxo-2-phenylethylthio)-pyrimidines series by spectral methods. The advantages of this scheme are discussed (the formation of intermediate sulfonates and the amination stage do not require harsh conditions and are carried out with satisfactory yields). The proposed scheme can be recommended in cases where the original substrate contains functional groups that are labile at high temperatures and sensitive to an acidic environment.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81873028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-24DOI: 10.33609/2708-129x.89.01.2023.3-17
Hanna Mas, O. Khomenko, I. Lisovskyi, V. Khomenko, S. Solopan, A. Belous
Lithium-ion batteries (LIBs) are widely used in electronic devices due to their numerous advantages, namely high energy density, high capacity, and long service life. One of the important components of a battery is the anode. In order to ensure high characteristics of LIB, the anode material must have high capacity, high ionic and electronic conductivities, and low cost. However, commonly used anode materials in lithium-ion batteries have a number of disadvantages. For example, a graphite-based anode is characterized by significant changes in volume during intercalation/deintercalation of lithium ions, high energy losses, and rapid deterioration of characteristics at high discharge/charge rates; Li4Ti5O12 have a low theoretical specific capacity, low electronic conductivity and low diffusion rate of lithium ions. Thus, the search for anode materials with high capacity and capability rate, as well as small volume change during lithium intercalation/deintercalation, remains an urgent task. A promising way may be the use of materials with intercalation pseudocapacitive behavior of charge accumulation, which occurs due to the intercalation of ions in tunnels or layers of active materials without a crystallographic phase transition. LixLa2/3-x/3TiO3 is well known as a superionic conductor with a high ionic conductivity σ ≈ 10–3 S/cm at room temperature. It crystallizes in a perovskite-type structure that consists of a framework of TiO6 octahedra stabilized by La atoms, and has numerous vacancies in the unoccupied positions 18d and 6a, that could participate in the storage and motion of Li ions. Electrochemical characteristics of LixLa2/3-x/3TiO3 (x = 0.35 and 0.5) anode materials with a perovskite structure were investigated and compared with the electrochemical characteristics of Li4Ti5O12 with a layered spinel structure.
{"title":"SYNTHESIS AND INVESTIGATION OF ELECTROCHEMICAL CHARACTERISTICS OF OXIDE Li-CONDUCTIVE MATERIALS WITH SPINEL AND PEROSKITE STRUCTURES","authors":"Hanna Mas, O. Khomenko, I. Lisovskyi, V. Khomenko, S. Solopan, A. Belous","doi":"10.33609/2708-129x.89.01.2023.3-17","DOIUrl":"https://doi.org/10.33609/2708-129x.89.01.2023.3-17","url":null,"abstract":"Lithium-ion batteries (LIBs) are widely used in electronic devices due to their numerous advantages, namely high energy density, high capacity, and long service life. One of the important components of a battery is the anode. In order to ensure high characteristics of LIB, the anode material must have high capacity, high ionic and electronic conductivities, and low cost. However, commonly used anode materials in lithium-ion batteries have a number of disadvantages. For example, a graphite-based anode is characterized by significant changes in volume during intercalation/deintercalation of lithium ions, high energy losses, and rapid deterioration of characteristics at high discharge/charge rates; Li4Ti5O12 have a low theoretical specific capacity, low electronic conductivity and low diffusion rate of lithium ions. \u0000Thus, the search for anode materials with high capacity and capability rate, as well as small volume change during lithium intercalation/deintercalation, remains an urgent task. A promising way may be the use of materials with intercalation pseudocapacitive behavior of charge accumulation, which occurs due to the intercalation of ions in tunnels or layers of active materials without a crystallographic phase transition. LixLa2/3-x/3TiO3 is well known as a superionic conductor with a high ionic conductivity σ ≈ 10–3 S/cm at room temperature. It crystallizes in a perovskite-type structure that consists of a framework of TiO6 octahedra stabilized by La atoms, and has numerous vacancies in the unoccupied positions 18d and 6a, that could participate in the storage and motion of Li ions. \u0000Electrochemical characteristics of LixLa2/3-x/3TiO3 (x = 0.35 and 0.5) anode materials with a perovskite structure were investigated and compared with the electrochemical characteristics of Li4Ti5O12 with a layered spinel structure.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85598330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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