Gabriel Radivoy | Universidad Nacional del Sur (original) (raw)
Papers by Gabriel Radivoy
The 24th International Electronic Conference on Synthetic Organic Chemistry, 2020
Beilstein Journal of Organic Chemistry, 2021
A new heterogeneous catalytic system consisting of cobalt nanoparticles (CoNPs) supported on MgO ... more A new heterogeneous catalytic system consisting of cobalt nanoparticles (CoNPs) supported on MgO and tert-butyl hydroperoxide (TBHP) as oxidant is presented. This CoNPs@MgO/t-BuOOH catalytic combination allowed the epoxidation of a variety of olefins with good to excellent yield and high selectivity. The catalyst preparation is simple and straightforward from commercially available starting materials and it could be recovered and reused maintaining its unaltered high activity.
Chemistry Proceedings, 2020
Copper nanoparticles (CuNPs) supported on TiO2 have shown to effectively catalyze the synthesis o... more Copper nanoparticles (CuNPs) supported on TiO2 have shown to effectively catalyze the synthesis of Z-alkenyl sulfides from activated alkynes and thiol derivatives, through an anti-Markovnikov process. Activated alkynes bearing an adjacent electron-withdrawing group gave good to excellent products conversions, while the unactivated alkynes did not react. In order to give an explanation to the reactivity observed from the experimental results and to know the most simple and representative structure of the catalyst, density functional theory (DFT) computational studies have been applied.
RSC Advances, 2021
An attractive approach to the synthesis of catechol derivates through thiol-yne click reaction is... more An attractive approach to the synthesis of catechol derivates through thiol-yne click reaction is presented. Compounds obtained were used in the preparation of CNPs.
Chemistry Proceedings, 2020
A new catalytic system consisting of Mn or Co nanoparticles supported on different materials (cel... more A new catalytic system consisting of Mn or Co nanoparticles supported on different materials (celite, zeolite, activated carbon, CeO2, ZnO, MgO, Nb2O5) have been studied for styrene epoxidation. The catalysts were easily prepared from commercially available starting materials. Reaction conditions were optimized by testing different solvents, reaction temperatures, oxidizing agents, and optimal catalyst loading. CoNPs/MgO and TBHP as a co-oxidant, in refluxing ACN, allowed total conversion to the epoxide with excellent yield and high selectivity.
Proceedings of The 16th International Electronic Conference on Synthetic Organic Chemistry, 2012
Synthesis, 2018
The selective semi-hydrogenation of terminal alkynes was efficiently performed, under mild reacti... more The selective semi-hydrogenation of terminal alkynes was efficiently performed, under mild reaction conditions (H2 balloon, 110 °C), promoted by a bimetallic nanocatalyst composed of copper and palladium nanoparticles (5:1 weight ratio) supported on mesostructured silica (MCM-48). The Cu-PdNPS@MCM-48 catalyst, which demonstrated to be highly chemoselective towards the alkyne functionality, is readily prepared from commercial materials and can be recovered and reused after thermal treatment followed by reduction under H2 atmosphere.
Bioorganic chemistry, 2018
A series of thirty-three alkynyl and β-ketophosphonates were evaluated for their in vitro acetyl-... more A series of thirty-three alkynyl and β-ketophosphonates were evaluated for their in vitro acetyl- and butyryl-cholinesterase (AChE and BChE) inhibitory activities using Ellman's spectrophotometric method. None of the examined compounds inhibited AChE activity at tested concentrations while twenty-nine of them showed significant and selective inhibition of BChE with IC values between 38.60 µM and 0.04 µM. In addition, structure-activity relationships were discussed. The most effective inhibitors were the dibutyl o-methoxyphenyl alkynylphosphonate 3dc and dibutyl o-methoxyphenyl β-ketophosphonate 4dc. Activities of most potent compounds were also compared with a commercial organophosphorus compound. These results could inspire the design of new inhibitors with stronger activity against BChE.
RSC Adv., 2016
A mild bottom-up synthesis of indium(0) nanoparticles (4.0 ± 0.5 nm) was developed and efficientl... more A mild bottom-up synthesis of indium(0) nanoparticles (4.0 ± 0.5 nm) was developed and efficiently applied in the allylation of carbonyl compounds.
The Journal of organic chemistry, Jan 3, 2016
A simple and mild methodology for the direct synthesis of alkynylphosphonates is presented. The r... more A simple and mild methodology for the direct synthesis of alkynylphosphonates is presented. The reaction of a variety of terminal alkynes with dialkyl phosphites in the presence Cu2O (14 mol%) led to the formation of the corresponding alkynylphosphonates in good to excellent yields. Reactions are performed under air, in acetonitrile as solvent, and in the absence of base or ligand additives. This new methodology is compatible with the presence of a wide variety of functional groups on the starting alkynes and can be scaled-up to a gram-scale.
ChemInform, 2015
It is found that alkynes conjugated with an aromatic ring or a carbon-carbon double bond afford β... more It is found that alkynes conjugated with an aromatic ring or a carbon-carbon double bond afford β-ketophosponates as main products, whereas aliphatic alkynes or alkynes conjugated with a carbonyl group afford the corresponding vinyl phosphonates as mixtures of E/Z-isomers.
Accounts of Chemical Research, 2015
very effective in the multicomponent and regioselective synthesis of 1,4-disubstituted-1,2,3triaz... more very effective in the multicomponent and regioselective synthesis of 1,4-disubstituted-1,2,3triazoles in water from organic halides as azido precursors; magnetically recoverable CuNPs (3.0 ± 0.8 nm)/MagSilica could be alternatively used for the same purpose under similar conditions. Incorporation of an aromatic substituent at the position 1 of the triazole could be accomplished using the same CuNPs/C catalytic system, but starting from aryl diazonium salts or anilines as azido precursors. CuNPs/C in water also catalyzed the regioselective double-click synthesis ofhydroxy-1,2,3-triazoles from epoxides. Furthermore, alkenes could be also used as azido precursors through a one-pot CuNPs/C-catalyzed azidosulfenylation-CuAAC sequential protocol, providing-methylsulfanyl-1,2,3-triazoles in a stereo-and regioselective manner. In all the types of reaction studied, CuNPs/C exhibited better behavior than some commercial copper catalysts as regards the metal loading, reaction time, yield and recyclability. Therefore, the results of this study also highlight the utility of nanosized copper in Click Chemistry when compared with bulk copper sources.
RSC Adv., 2015
Ligand- and base-free direct synthesis of β-keto- and vinyl phosphonates catalysed by CuNPs/ZnO u... more Ligand- and base-free direct synthesis of β-keto- and vinyl phosphonates catalysed by CuNPs/ZnO under air. Selectivity dependent on alkyne nature.
Proceedings of The 17th International Electronic Conference on Synthetic Organic Chemistry, 2013
Applied Catalysis A: General, 2014
The Suzuki-Miyaura cross-coupling reaction between p-iodotoluene and phenylboronic acid is carrie... more The Suzuki-Miyaura cross-coupling reaction between p-iodotoluene and phenylboronic acid is carried out over a series of ceria catalysts, at 150 • C, under N 2 atmosphere, employing DMF as the solvent. The ceria catalysts present different BET area (determined from N 2 isotherms at 77 K), different Ce 4+ /Ce 3+ ratio (as measured by XPS), and different concentration and strength of acid sites (as measured by potentiometric titration with n-butylamine). The activity of the different samples depends on the concentration and strength of acid sites, although the participation of Ce 3+ centers should not be neglected. Ceria catalysts are less active and less selective than a Pd/SiO 2 sample. Although the catalytic performance of ceria catalysts is lower than the one corresponding to Pd/SiO 2 , the fact that a transition metal-free catalyst is active for SM reaction is highlighted.
Proceedings of The 17th International Electronic Conference on Synthetic Organic Chemistry, 2013
A versatile and straightforward strategy to construct a xanthone skeleton via an intermolecular c... more A versatile and straightforward strategy to construct a xanthone skeleton via an intermolecular catalytic coupling of 2-substituted benzaldehydes and a wide range of phenols has been developed. For this purpose, a novel and magnetically recoverable catalyst consisting of copper nanoparticles on nanosized silica coated maghemite in absence of ligand is presented. The reaction proceeds smoothly without the need to preactivate the aldehyde carbonyl group. It can tolerate various functional groups and provides an efficient protocol for the generation of a small library of xanthones in high yield.
Tetrahedron Letters, 2012
Abstract A simple one-pot procedure for the direct reductive amination of aldehydes using lithium... more Abstract A simple one-pot procedure for the direct reductive amination of aldehydes using lithium powder and a catalytic amount of 4,4′-di- tert -butylbiphenyl (DTBB) or a polymer supported naphthalene as reducing system is described. The direct reductive amination of a variety of aldehydes with primary amines was achieved simply by adding a mixture of the corresponding carbonyl compound and the amine, over a solution of the lithium arenide in THF at room temperature. For most of the substrates tested the main reaction products were the secondary amines along with variable amounts of the corresponding alcohol and/or imine products. Theoretical DFT calculations have been applied in order to explain the differences in reactivity observed for aromatic substrates.
The 24th International Electronic Conference on Synthetic Organic Chemistry, 2020
Beilstein Journal of Organic Chemistry, 2021
A new heterogeneous catalytic system consisting of cobalt nanoparticles (CoNPs) supported on MgO ... more A new heterogeneous catalytic system consisting of cobalt nanoparticles (CoNPs) supported on MgO and tert-butyl hydroperoxide (TBHP) as oxidant is presented. This CoNPs@MgO/t-BuOOH catalytic combination allowed the epoxidation of a variety of olefins with good to excellent yield and high selectivity. The catalyst preparation is simple and straightforward from commercially available starting materials and it could be recovered and reused maintaining its unaltered high activity.
Chemistry Proceedings, 2020
Copper nanoparticles (CuNPs) supported on TiO2 have shown to effectively catalyze the synthesis o... more Copper nanoparticles (CuNPs) supported on TiO2 have shown to effectively catalyze the synthesis of Z-alkenyl sulfides from activated alkynes and thiol derivatives, through an anti-Markovnikov process. Activated alkynes bearing an adjacent electron-withdrawing group gave good to excellent products conversions, while the unactivated alkynes did not react. In order to give an explanation to the reactivity observed from the experimental results and to know the most simple and representative structure of the catalyst, density functional theory (DFT) computational studies have been applied.
RSC Advances, 2021
An attractive approach to the synthesis of catechol derivates through thiol-yne click reaction is... more An attractive approach to the synthesis of catechol derivates through thiol-yne click reaction is presented. Compounds obtained were used in the preparation of CNPs.
Chemistry Proceedings, 2020
A new catalytic system consisting of Mn or Co nanoparticles supported on different materials (cel... more A new catalytic system consisting of Mn or Co nanoparticles supported on different materials (celite, zeolite, activated carbon, CeO2, ZnO, MgO, Nb2O5) have been studied for styrene epoxidation. The catalysts were easily prepared from commercially available starting materials. Reaction conditions were optimized by testing different solvents, reaction temperatures, oxidizing agents, and optimal catalyst loading. CoNPs/MgO and TBHP as a co-oxidant, in refluxing ACN, allowed total conversion to the epoxide with excellent yield and high selectivity.
Proceedings of The 16th International Electronic Conference on Synthetic Organic Chemistry, 2012
Synthesis, 2018
The selective semi-hydrogenation of terminal alkynes was efficiently performed, under mild reacti... more The selective semi-hydrogenation of terminal alkynes was efficiently performed, under mild reaction conditions (H2 balloon, 110 °C), promoted by a bimetallic nanocatalyst composed of copper and palladium nanoparticles (5:1 weight ratio) supported on mesostructured silica (MCM-48). The Cu-PdNPS@MCM-48 catalyst, which demonstrated to be highly chemoselective towards the alkyne functionality, is readily prepared from commercial materials and can be recovered and reused after thermal treatment followed by reduction under H2 atmosphere.
Bioorganic chemistry, 2018
A series of thirty-three alkynyl and β-ketophosphonates were evaluated for their in vitro acetyl-... more A series of thirty-three alkynyl and β-ketophosphonates were evaluated for their in vitro acetyl- and butyryl-cholinesterase (AChE and BChE) inhibitory activities using Ellman's spectrophotometric method. None of the examined compounds inhibited AChE activity at tested concentrations while twenty-nine of them showed significant and selective inhibition of BChE with IC values between 38.60 µM and 0.04 µM. In addition, structure-activity relationships were discussed. The most effective inhibitors were the dibutyl o-methoxyphenyl alkynylphosphonate 3dc and dibutyl o-methoxyphenyl β-ketophosphonate 4dc. Activities of most potent compounds were also compared with a commercial organophosphorus compound. These results could inspire the design of new inhibitors with stronger activity against BChE.
RSC Adv., 2016
A mild bottom-up synthesis of indium(0) nanoparticles (4.0 ± 0.5 nm) was developed and efficientl... more A mild bottom-up synthesis of indium(0) nanoparticles (4.0 ± 0.5 nm) was developed and efficiently applied in the allylation of carbonyl compounds.
The Journal of organic chemistry, Jan 3, 2016
A simple and mild methodology for the direct synthesis of alkynylphosphonates is presented. The r... more A simple and mild methodology for the direct synthesis of alkynylphosphonates is presented. The reaction of a variety of terminal alkynes with dialkyl phosphites in the presence Cu2O (14 mol%) led to the formation of the corresponding alkynylphosphonates in good to excellent yields. Reactions are performed under air, in acetonitrile as solvent, and in the absence of base or ligand additives. This new methodology is compatible with the presence of a wide variety of functional groups on the starting alkynes and can be scaled-up to a gram-scale.
ChemInform, 2015
It is found that alkynes conjugated with an aromatic ring or a carbon-carbon double bond afford β... more It is found that alkynes conjugated with an aromatic ring or a carbon-carbon double bond afford β-ketophosponates as main products, whereas aliphatic alkynes or alkynes conjugated with a carbonyl group afford the corresponding vinyl phosphonates as mixtures of E/Z-isomers.
Accounts of Chemical Research, 2015
very effective in the multicomponent and regioselective synthesis of 1,4-disubstituted-1,2,3triaz... more very effective in the multicomponent and regioselective synthesis of 1,4-disubstituted-1,2,3triazoles in water from organic halides as azido precursors; magnetically recoverable CuNPs (3.0 ± 0.8 nm)/MagSilica could be alternatively used for the same purpose under similar conditions. Incorporation of an aromatic substituent at the position 1 of the triazole could be accomplished using the same CuNPs/C catalytic system, but starting from aryl diazonium salts or anilines as azido precursors. CuNPs/C in water also catalyzed the regioselective double-click synthesis ofhydroxy-1,2,3-triazoles from epoxides. Furthermore, alkenes could be also used as azido precursors through a one-pot CuNPs/C-catalyzed azidosulfenylation-CuAAC sequential protocol, providing-methylsulfanyl-1,2,3-triazoles in a stereo-and regioselective manner. In all the types of reaction studied, CuNPs/C exhibited better behavior than some commercial copper catalysts as regards the metal loading, reaction time, yield and recyclability. Therefore, the results of this study also highlight the utility of nanosized copper in Click Chemistry when compared with bulk copper sources.
RSC Adv., 2015
Ligand- and base-free direct synthesis of β-keto- and vinyl phosphonates catalysed by CuNPs/ZnO u... more Ligand- and base-free direct synthesis of β-keto- and vinyl phosphonates catalysed by CuNPs/ZnO under air. Selectivity dependent on alkyne nature.
Proceedings of The 17th International Electronic Conference on Synthetic Organic Chemistry, 2013
Applied Catalysis A: General, 2014
The Suzuki-Miyaura cross-coupling reaction between p-iodotoluene and phenylboronic acid is carrie... more The Suzuki-Miyaura cross-coupling reaction between p-iodotoluene and phenylboronic acid is carried out over a series of ceria catalysts, at 150 • C, under N 2 atmosphere, employing DMF as the solvent. The ceria catalysts present different BET area (determined from N 2 isotherms at 77 K), different Ce 4+ /Ce 3+ ratio (as measured by XPS), and different concentration and strength of acid sites (as measured by potentiometric titration with n-butylamine). The activity of the different samples depends on the concentration and strength of acid sites, although the participation of Ce 3+ centers should not be neglected. Ceria catalysts are less active and less selective than a Pd/SiO 2 sample. Although the catalytic performance of ceria catalysts is lower than the one corresponding to Pd/SiO 2 , the fact that a transition metal-free catalyst is active for SM reaction is highlighted.
Proceedings of The 17th International Electronic Conference on Synthetic Organic Chemistry, 2013
A versatile and straightforward strategy to construct a xanthone skeleton via an intermolecular c... more A versatile and straightforward strategy to construct a xanthone skeleton via an intermolecular catalytic coupling of 2-substituted benzaldehydes and a wide range of phenols has been developed. For this purpose, a novel and magnetically recoverable catalyst consisting of copper nanoparticles on nanosized silica coated maghemite in absence of ligand is presented. The reaction proceeds smoothly without the need to preactivate the aldehyde carbonyl group. It can tolerate various functional groups and provides an efficient protocol for the generation of a small library of xanthones in high yield.
Tetrahedron Letters, 2012
Abstract A simple one-pot procedure for the direct reductive amination of aldehydes using lithium... more Abstract A simple one-pot procedure for the direct reductive amination of aldehydes using lithium powder and a catalytic amount of 4,4′-di- tert -butylbiphenyl (DTBB) or a polymer supported naphthalene as reducing system is described. The direct reductive amination of a variety of aldehydes with primary amines was achieved simply by adding a mixture of the corresponding carbonyl compound and the amine, over a solution of the lithium arenide in THF at room temperature. For most of the substrates tested the main reaction products were the secondary amines along with variable amounts of the corresponding alcohol and/or imine products. Theoretical DFT calculations have been applied in order to explain the differences in reactivity observed for aromatic substrates.