: The transition metal-catalyzed chemical transformation of organic electrophiles, and organometallic reagents have turned up as an exceedingly robust synthetic tool. The evolution of transition metal catalysts has attained a stage of civilization that authorizes for an extensive scope of chemical bonds formation partners to be combined efficiently. The applications of Cu-based nanoparticles have received great attention owing to the earth-abundant, low toxicity and inexpensive. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. In this study, poly(acrylonitrile) was synthesized by undergoes free-radical initiation process and followed by Beckmann rearrangement with hydroxylamine solution converted into the poly(amidoxime) ligand and anchored the copper onto poly(amidoxime). Cu(II)@PAM was characterized using different techniques such as FTIR, FESEM, EDX, TEM, TGA, DSC, ICP-OES, and XPS analyses. The Cu(II)@PAM showed high stability and high catalytic activity in a wide variety of electrophilic substituted phenols with substituted aryl/benzyl halides. 0.15 mol%, ±3 mg of Cu(II)@PAM could efficiently promote Ullmann reaction to give the corresponding coupling product up to 99 % yields. The complex was easy separated and recovered from the reaction mixture by simple filtration.
{"title":"Highly Active Pandanus Nanocellulose-Supported Poly(amidoxime) Copper (II) Complex for Ullmann Cross-Coupling Reaction","authors":"C. Fui, Md. Hafizur Rahman, T. Ting, M. Sarjadi","doi":"10.3390/eccs2020-07530","DOIUrl":"https://doi.org/10.3390/eccs2020-07530","url":null,"abstract":": The transition metal-catalyzed chemical transformation of organic electrophiles, and organometallic reagents have turned up as an exceedingly robust synthetic tool. The evolution of transition metal catalysts has attained a stage of civilization that authorizes for an extensive scope of chemical bonds formation partners to be combined efficiently. The applications of Cu-based nanoparticles have received great attention owing to the earth-abundant, low toxicity and inexpensive. Due to these characteristics, copper nanoparticles have generated a great deal of interest especially in the field of catalysis. In this study, poly(acrylonitrile) was synthesized by undergoes free-radical initiation process and followed by Beckmann rearrangement with hydroxylamine solution converted into the poly(amidoxime) ligand and anchored the copper onto poly(amidoxime). Cu(II)@PAM was characterized using different techniques such as FTIR, FESEM, EDX, TEM, TGA, DSC, ICP-OES, and XPS analyses. The Cu(II)@PAM showed high stability and high catalytic activity in a wide variety of electrophilic substituted phenols with substituted aryl/benzyl halides. 0.15 mol%, ±3 mg of Cu(II)@PAM could efficiently promote Ullmann reaction to give the corresponding coupling product up to 99 % yields. The complex was easy separated and recovered from the reaction mixture by simple filtration.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114585755","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}
Concetta Ruocco, V. Palma, Marta Cortese, M. Martino
: In this work, Pt-Ni/CeO 2 -SiO 2, as well as Ru-Ni/CeO 2 -SiO 2 catalysts, were obtained at different loadings of the noble metal (in the interval 0–3 wt%) and tested for oxidative steam reforming of ethanol. Stability performance was evaluated at 500 °C for 25 h under a steam to ethanol ratio of 4 and an oxygen to ethanol ratio of 0.5. The weight hourly space velocity was fixed to 60 h − 1 , which is considerably higher than the typical values selected for such processes. All the catalysts deactivated with time-on-stream, due to the severe operative conditions selected. However, the highest ethanol conversion (above 95%) and hydrogen yield (30%) at the end of the test were recorded over the 2 wt%Pt-10 wt%Ni/CeO 2 -SiO 2 catalyst, which also displayed a limited carbon formation rate (1.5 × 10 − 6 g coke ·g catalyst − 1 ·g carbon,fed − 1 ·h − 1 , reduced almost 5 times compared to the samples that had a Pt or Ru content of 0.5 wt%). Thus, the latter catalyst was identified as a promising candidate for future tests under real bioethanol mixture.
{"title":"Noble Metals-Based Catalysts for Hydrogen Production via Bioethanol Reforming in A Fluidized Bed Reactor","authors":"Concetta Ruocco, V. Palma, Marta Cortese, M. Martino","doi":"10.3390/eccs2020-07543","DOIUrl":"https://doi.org/10.3390/eccs2020-07543","url":null,"abstract":": In this work, Pt-Ni/CeO 2 -SiO 2, as well as Ru-Ni/CeO 2 -SiO 2 catalysts, were obtained at different loadings of the noble metal (in the interval 0–3 wt%) and tested for oxidative steam reforming of ethanol. Stability performance was evaluated at 500 °C for 25 h under a steam to ethanol ratio of 4 and an oxygen to ethanol ratio of 0.5. The weight hourly space velocity was fixed to 60 h − 1 , which is considerably higher than the typical values selected for such processes. All the catalysts deactivated with time-on-stream, due to the severe operative conditions selected. However, the highest ethanol conversion (above 95%) and hydrogen yield (30%) at the end of the test were recorded over the 2 wt%Pt-10 wt%Ni/CeO 2 -SiO 2 catalyst, which also displayed a limited carbon formation rate (1.5 × 10 − 6 g coke ·g catalyst − 1 ·g carbon,fed − 1 ·h − 1 , reduced almost 5 times compared to the samples that had a Pt or Ru content of 0.5 wt%). Thus, the latter catalyst was identified as a promising candidate for future tests under real bioethanol mixture.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127649790","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}
J. Ścianowski, Agata J. Pacuła-Miszewska, Magdalena Obieziurska-Fabisiak, A. Laskowska
: Designing a highly active and selective Se-therapeutic that mimics the activity of the antioxidant enzyme glutathione peroxidase (GPx) still remains a challenge. Since the discovery of ebselen ( N -phenyl-1,2-benzisoselenazol-3(2H)-one) and its ability to act as a GPx mimetic, the search for more effective peroxide scavengers has become a “hot topic” in this field of research. Herein, we present several modifications of the benzisoselenazolone core that enable improving the antioxidant and anticancer potential of the basic ebselen structure. These transformations include (a) the installation of chiral terpene skeletons, from p -menthane, pinane, and carane systems, on the nitrogen atom; (b) exchange of the carbonyl oxygen atom for sulfur to obtain thiocarbonyl derivatives; (c) oxidation of the selenium moiety resulting in a series of benzenoselenenic acids and their further transformation to corresponding water-soluble potassium salts; and (d) attachment of an additional phenyl group leading to variously N -substituted unsymmetrical phenylselenides with an o -amido function. All of the synthetized compounds were tested as antioxidants and antiproliferative agents. Conclusions concerning the structure–activity correlation, including the difference in the reactivity of specific Se-moieties (-Se-N-, -SeOOH, -SeOOK, -SePh), N -substituents (the influence of bulky aliphatic moiety and the three-dimensional orientation of atoms), and incorporated heteroatoms (-C=O, -C=S) are presented.
设计一种高活性和选择性的硒治疗药物，模仿抗氧化酶谷胱甘肽过氧化物酶(GPx)的活性，仍然是一个挑战。自从发现ebselen (N -苯基-1,2-苯并异硒唑-3(2H)- 1)及其作为GPx模拟物的能力以来，寻找更有效的过氧化物清除剂已成为该研究领域的“热门话题”。在此，我们提出了几种对苯并异硒代唑酮核心的修饰，从而提高了碱性艾布selen结构的抗氧化和抗癌潜力。这些转化包括(a)从对甲烷、蒎烷和烷烃体系在氮原子上安装手性萜骨架;(b)羰基氧原子与硫交换，得到硫羰基衍生物;(c)硒部分氧化产生一系列苯硒酸，并进一步转化为相应的水溶性钾盐;和(d)附加苯基的连接导致具有o -酰胺功能的各种N取代的不对称苯硒化物。所有合成的化合物都作为抗氧化剂和抗增殖剂进行了测试。给出了结构-活性相关性的结论，包括特定的se -基团(- se -N-， - seooh， - seook， - seph)， N-取代基(庞大的脂肪基团和原子的三维取向的影响)和掺入的杂原子(- c =O， - c =S)的反应性差异。
{"title":"Divers Transformations Leading to New Potent GPx Mimetics","authors":"J. Ścianowski, Agata J. Pacuła-Miszewska, Magdalena Obieziurska-Fabisiak, A. Laskowska","doi":"10.3390/eccs2020-07546","DOIUrl":"https://doi.org/10.3390/eccs2020-07546","url":null,"abstract":": Designing a highly active and selective Se-therapeutic that mimics the activity of the antioxidant enzyme glutathione peroxidase (GPx) still remains a challenge. Since the discovery of ebselen ( N -phenyl-1,2-benzisoselenazol-3(2H)-one) and its ability to act as a GPx mimetic, the search for more effective peroxide scavengers has become a “hot topic” in this field of research. Herein, we present several modifications of the benzisoselenazolone core that enable improving the antioxidant and anticancer potential of the basic ebselen structure. These transformations include (a) the installation of chiral terpene skeletons, from p -menthane, pinane, and carane systems, on the nitrogen atom; (b) exchange of the carbonyl oxygen atom for sulfur to obtain thiocarbonyl derivatives; (c) oxidation of the selenium moiety resulting in a series of benzenoselenenic acids and their further transformation to corresponding water-soluble potassium salts; and (d) attachment of an additional phenyl group leading to variously N -substituted unsymmetrical phenylselenides with an o -amido function. All of the synthetized compounds were tested as antioxidants and antiproliferative agents. Conclusions concerning the structure–activity correlation, including the difference in the reactivity of specific Se-moieties (-Se-N-, -SeOOH, -SeOOK, -SePh), N -substituents (the influence of bulky aliphatic moiety and the three-dimensional orientation of atoms), and incorporated heteroatoms (-C=O, -C=S) are presented.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133963340","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}
: Carbasugars are a wide group of carbohydrate mimetics in which the ring oxygen is replaced by a methylene group. The high importance of these compounds is related to their interesting biological and pharmacological properties which are the matter of current studies. In our work, a concise synthesis of carbasugars from naturally occurring D -pentoses is presented. The one-pot seleno-Michael reaction connected with intramolecular aldol reaction is a key step of the carbasugar core asymmetric synthesis. Further transformation of obtained carbasugar moiety led to different bioactive compounds. Tandem seleno-Michael reaction conjugated with oxidation/elimination step of in situ generated nucleophile was described a few years ago in the intermolecular variant. In our work, we present the first example of this reaction in an intramolecular way which leads to a previously inaccessible cyclic product of Morita–Baylis– Hillman reaction. Conducted experiments allowed us to obtain cyclic products with high yields and good diastereoisomeric excesses.
{"title":"Intramolecular Tandem seleno-Michael/Aldol Reaction - Novel Strategy in Carbasugars Synthesis","authors":"Piotr Banachowicz, N. Biduś, Szymon Buda","doi":"10.3390/eccs2020-07571","DOIUrl":"https://doi.org/10.3390/eccs2020-07571","url":null,"abstract":": Carbasugars are a wide group of carbohydrate mimetics in which the ring oxygen is replaced by a methylene group. The high importance of these compounds is related to their interesting biological and pharmacological properties which are the matter of current studies. In our work, a concise synthesis of carbasugars from naturally occurring D -pentoses is presented. The one-pot seleno-Michael reaction connected with intramolecular aldol reaction is a key step of the carbasugar core asymmetric synthesis. Further transformation of obtained carbasugar moiety led to different bioactive compounds. Tandem seleno-Michael reaction conjugated with oxidation/elimination step of in situ generated nucleophile was described a few years ago in the intermolecular variant. In our work, we present the first example of this reaction in an intramolecular way which leads to a previously inaccessible cyclic product of Morita–Baylis– Hillman reaction. Conducted experiments allowed us to obtain cyclic products with high yields and good diastereoisomeric excesses.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114605552","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}
F. Sakibaev, M. Holyavka, V. Koroleva, V. Artyukhov
: Thermotoga maritima beta-fructosidases are enzymes that release beta-D-fructose from sucrose, raffinose, and fructan polymers such as inulin. The surfaces of beta-fructosidases 1UYP and 1W2T from Thermotoga maritima were studied in this work. It was showed that amino acids are not distributed equally on the surfaces of the enzymes. Several clusters of charged and hydrophobic residues were detected at pH 7.0. Such clusters were detected by calculation of the distances between them. It was determined that on surfaces of beta-fructosidases PDB ID: 1UYP and PDB ID: 1W2T, 96% and 95% of charged amino acids and also 50% and 42% of hydrophobic amino acids form clusters, respectively. Six clusters of charged amino acids on the surface of beta-fructosidase 1UYP and five clusters on the surface of beta-fructosidase 1W2T were detected. The composition of such clusters is presented. Both types of beta-fructosidase have three clusters of hydrophobic amino acids on their surface. These facts should be considered when choosing immobilization conditions. It was shown that a charged matrix is more promising for the immobilization of beta-fructosidases 1UYP and 1W2T from Thermotoga maritima due to the possibility of binding without any significant loss of activity due to their overlapping active center. Hydrophobic carriers are less promising due to the probable active site overlap. Such binding may have a loss of enzyme activity as a result.
{"title":"Distribution of Charged and Hydrophobic Amino Acids on the Surfaces of Two Types of Beta-Fructosidase from Thermotoga maritima","authors":"F. Sakibaev, M. Holyavka, V. Koroleva, V. Artyukhov","doi":"10.3390/eccs2020-07550","DOIUrl":"https://doi.org/10.3390/eccs2020-07550","url":null,"abstract":": Thermotoga maritima beta-fructosidases are enzymes that release beta-D-fructose from sucrose, raffinose, and fructan polymers such as inulin. The surfaces of beta-fructosidases 1UYP and 1W2T from Thermotoga maritima were studied in this work. It was showed that amino acids are not distributed equally on the surfaces of the enzymes. Several clusters of charged and hydrophobic residues were detected at pH 7.0. Such clusters were detected by calculation of the distances between them. It was determined that on surfaces of beta-fructosidases PDB ID: 1UYP and PDB ID: 1W2T, 96% and 95% of charged amino acids and also 50% and 42% of hydrophobic amino acids form clusters, respectively. Six clusters of charged amino acids on the surface of beta-fructosidase 1UYP and five clusters on the surface of beta-fructosidase 1W2T were detected. The composition of such clusters is presented. Both types of beta-fructosidase have three clusters of hydrophobic amino acids on their surface. These facts should be considered when choosing immobilization conditions. It was shown that a charged matrix is more promising for the immobilization of beta-fructosidases 1UYP and 1W2T from Thermotoga maritima due to the possibility of binding without any significant loss of activity due to their overlapping active center. Hydrophobic carriers are less promising due to the probable active site overlap. Such binding may have a loss of enzyme activity as a result.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115757169","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}
E. Nikolaivits, Phaedra Dimopoulou, Veselin Maslak, J. Nikodinović-Runić, E. Topakas
Plastic waste poses an enormous environmental problem as a result of soil and ocean contamination, causing the release of microplastics that end up in humans through the food web. Enzymatic degradation of plastics has emerged as an alternative to traditional recycling processes. In the present work, we used bioinfomatics tools to discover a gene coding for a putative polyester degrading enzyme (polyesterase). The gene was heterologously expressed, purified and biochemically characterized. Furthermore, its ability to degrade polyethylene terephthalate (PET) model substrates and synthetic plastics was assessed.
{"title":"Discovery and Biochemical Characterization of a Novel Polyesterase for the Degradation of Synthetic Plastics","authors":"E. Nikolaivits, Phaedra Dimopoulou, Veselin Maslak, J. Nikodinović-Runić, E. Topakas","doi":"10.3390/eccs2020-07572","DOIUrl":"https://doi.org/10.3390/eccs2020-07572","url":null,"abstract":"Plastic waste poses an enormous environmental problem as a result of soil and ocean contamination, causing the release of microplastics that end up in humans through the food web. Enzymatic degradation of plastics has emerged as an alternative to traditional recycling processes. In the present work, we used bioinfomatics tools to discover a gene coding for a putative polyester degrading enzyme (polyesterase). The gene was heterologously expressed, purified and biochemically characterized. Furthermore, its ability to degrade polyethylene terephthalate (PET) model substrates and synthetic plastics was assessed.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132200441","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}
F. Cavalcanti, J. Poissonnier, T. Vandevyvere, R. Giudici, R. Alves, M. Schmal, J. Thybaut
: The development of microkinetic models allows gaining an understanding of fundamental catalyst surface phenomena in terms of elementary reaction steps without a priori defining a rate-determining step, yielding more meaningful and physically reliable reaction rates. This work aimed at developing such a microkinetic model that accurately describes the Water-Gas Shift (WGS) reaction, i.e., one of the major routes for hydrogen production, over cobalt (Co) catalysts supported on multi-walled carbon nanotubes (MWCNTs). Co is known for its sulfur-tolerance and the functionalized MWCNT support has exceptional conductivity properties and defects that facilitate electron transfer on its surface. The model was formulated based on a well-known mechanism for the WGS reaction involving the highly reactive carboxyl (COOH*) intermediate. The kinetic parameters were computed by a combination of calculation via theoretical prediction models (such as the Collision and Transition-State theory) and via regression to the experimental data. The derived system of differential-algebraic equations was solved using the DDAPLUS package available in the Athena VISUAL Studio. The developed model was capable of simulating the experimental data (R² = 0.96), presenting statistically significant kinetic parameters. Furthermore, some of the catalyst descriptors in the model have been related to the catalyst properties as determined by characterization techniques, such as the specific surface area (S P = 22,000 m²/kg cat ) and the density of active sites ( σ = 0.012 mol Act.Surf. /kg cat ). The modelling and characterization efforts allowed identifying the COOH* formation reaction (CO* + OH* → COOH* + *) as the surface reaction with the highest activation energy. Optimal catalyst performance, resulting in a CO conversion exceeding 85%, was simulated at elevated temperatures (350–450 °C) and space times (70–80 kg·s/mol), in agreement with the experimental observations.
{"title":"Microkinetic Modeling for the Water-Gas Shift Reaction over Cobalt Catalysts Supported on Multi-Walled Carbon Nanotubes","authors":"F. Cavalcanti, J. Poissonnier, T. Vandevyvere, R. Giudici, R. Alves, M. Schmal, J. Thybaut","doi":"10.3390/eccs2020-07581","DOIUrl":"https://doi.org/10.3390/eccs2020-07581","url":null,"abstract":": The development of microkinetic models allows gaining an understanding of fundamental catalyst surface phenomena in terms of elementary reaction steps without a priori defining a rate-determining step, yielding more meaningful and physically reliable reaction rates. This work aimed at developing such a microkinetic model that accurately describes the Water-Gas Shift (WGS) reaction, i.e., one of the major routes for hydrogen production, over cobalt (Co) catalysts supported on multi-walled carbon nanotubes (MWCNTs). Co is known for its sulfur-tolerance and the functionalized MWCNT support has exceptional conductivity properties and defects that facilitate electron transfer on its surface. The model was formulated based on a well-known mechanism for the WGS reaction involving the highly reactive carboxyl (COOH*) intermediate. The kinetic parameters were computed by a combination of calculation via theoretical prediction models (such as the Collision and Transition-State theory) and via regression to the experimental data. The derived system of differential-algebraic equations was solved using the DDAPLUS package available in the Athena VISUAL Studio. The developed model was capable of simulating the experimental data (R² = 0.96), presenting statistically significant kinetic parameters. Furthermore, some of the catalyst descriptors in the model have been related to the catalyst properties as determined by characterization techniques, such as the specific surface area (S P = 22,000 m²/kg cat ) and the density of active sites ( σ = 0.012 mol Act.Surf. /kg cat ). The modelling and characterization efforts allowed identifying the COOH* formation reaction (CO* + OH* → COOH* + *) as the surface reaction with the highest activation energy. Optimal catalyst performance, resulting in a CO conversion exceeding 85%, was simulated at elevated temperatures (350–450 °C) and space times (70–80 kg·s/mol), in agreement with the experimental observations.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"72 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130541425","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}
Pâmella S. Cordeiro, M. Prado, José Neto, Vanessa Nascimento
: Organocalcogenides, in particular, organoselenium compounds, have been widely studied due to their large number of synthetic and biological applications. Among organoselenium compounds, a class of bis-selenide-alkene derivatives has attracted attention. Recently, some studies have been developed for the synthesis of vinyl chalcogen derivatives, since these are also highly valuable intermediates in several synthetic applications. However, the methodologies developed so far have extensive reaction times, and use toxic solvents as well as heavy metals. Therefore, there is an emerging need to develop protocols for the synthesis of these molecules that are in accordance with the principles of green chemistry. In this work, we developed an alternative synthesis of bis-selenium-alkene derivatives, through an environmentally appropriate methodology. Reaction optimization was evaluated from the diphenylacetylene and diphenyl diselenide, using I 2 /DMSO as a catalytic system under microwave irradiation or conventional heating. The variations of these conditions were carried out through different equivalences between the reagents, the amount of catalyst (I 2 ), temperature, DMSO and the reaction process (Microwave or conventional). Even now, it was found that the best established condition was using diphenylacetylene, diphenyl diselenide, 30 mol% I 2 in DMSO, under microwave irradiation at 100 °C for 10 min. In this condition, the product was obtained in 82% yield and its characterization was performed using 1H and 13C NMR spectroscopy. Therefore, the methodology that is being developed, in addition to perfectly attending to the principles of green chemistry, will allow to evaluate the reaction scope using different alkenes and diselenides or even disulfides and ditellurides.
{"title":"Efficient Eco-Friendly Solvent-Free Obtaining Bis-Selenium-Alkenes with High Biological Potential","authors":"Pâmella S. Cordeiro, M. Prado, José Neto, Vanessa Nascimento","doi":"10.3390/eccs2020-07566","DOIUrl":"https://doi.org/10.3390/eccs2020-07566","url":null,"abstract":": Organocalcogenides, in particular, organoselenium compounds, have been widely studied due to their large number of synthetic and biological applications. Among organoselenium compounds, a class of bis-selenide-alkene derivatives has attracted attention. Recently, some studies have been developed for the synthesis of vinyl chalcogen derivatives, since these are also highly valuable intermediates in several synthetic applications. However, the methodologies developed so far have extensive reaction times, and use toxic solvents as well as heavy metals. Therefore, there is an emerging need to develop protocols for the synthesis of these molecules that are in accordance with the principles of green chemistry. In this work, we developed an alternative synthesis of bis-selenium-alkene derivatives, through an environmentally appropriate methodology. Reaction optimization was evaluated from the diphenylacetylene and diphenyl diselenide, using I 2 /DMSO as a catalytic system under microwave irradiation or conventional heating. The variations of these conditions were carried out through different equivalences between the reagents, the amount of catalyst (I 2 ), temperature, DMSO and the reaction process (Microwave or conventional). Even now, it was found that the best established condition was using diphenylacetylene, diphenyl diselenide, 30 mol% I 2 in DMSO, under microwave irradiation at 100 °C for 10 min. In this condition, the product was obtained in 82% yield and its characterization was performed using 1H and 13C NMR spectroscopy. Therefore, the methodology that is being developed, in addition to perfectly attending to the principles of green chemistry, will allow to evaluate the reaction scope using different alkenes and diselenides or even disulfides and ditellurides.","PeriodicalId":151361,"journal":{"name":"Proceedings of 1st International Electronic Conference on Catalysis Sciences","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121712143","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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