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Gilson Zeni - One of the best experts on this subject based on the ideXlab platform.
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Electrophilic Cyclization Involving Carbon–Selenium/Carbon–Halide Bond Formation: Synthesis of 3‑Substituted Selenophenes
2018Co-Authors: Kamila Kaiser Casola, Matheus Rick Gomes, Davi Fernando Back, Gilson ZeniAbstract:The butylselanyl propargyl alcohols reacted with iodine to afford 3-iodoSelenophenes. The change of nucleophile position from propargyl to homopropargyl was crucial for the aromatization and formation of Selenophene rings. The experiments revealed that bromine and N-bromosuccinimide were not able to cyclize the butylselanyl propargyl alcohols; however, when the bromine source was copper(II) bromide the corresponding 3-bromoSelenophenes were obtained in good yields. In addition, the reaction of butylselanyl propargyl alcohols with diorganyl diselenides catalyzed by copper(I) iodide gave the 3-(organoselanyl)Selenophenes. The reaction took place with aromatic rings substituted by either electron-donating or -withdrawing groups in the alkynes and propargyl positions. The steric effects of substituents were dominant in determining the yields, whereas electronic effects had only a minor influence. Furthermore, by monitoring the reaction by 1H NMR, we were able to identify the key intermediate, which supported the elaboration of a proposed reaction mechanism. The 3-iodoSelenophenes prepared allowed the synthesis of multifunctional Selenophenes via application in metal-catalyzed coupling reactions, such as Sonogashira, Ullmann and Suzuki type reactions
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synthesis and antidepressant like activity of Selenophenes obtained via iron iii phseseph mediated cyclization of z selenoenynes
Organic and Biomolecular Chemistry, 2012Co-Authors: Bibiana M Gai, Andre L Stein, Juliano A Roehrs, Filipe N Bilheri, Cristina W Nogueira, Gilson ZeniAbstract:We present here the synthesis and antidepressant-like action of a series of 2,5-disubstituted-3-(organoseleno)-Selenophenes prepared by a novel synthetic route, the FeCl3–diorganyl dichalcogenide-mediated intramolecular cyclization of (Z)-chalcogenoenynes. The cyclized products were obtained in good yields. The results showed that 2c, 2d, 2e and 2o, evaluated in the mouse forced-swimming test, elicited an antidepressant-like activity. The studies clearly show that the phenyl group at the 2-position and an organoselenium group at the 3-position of the Selenophene ring are essential for the antidepressant-like activity of Selenophenes. A close inspection of the results also revealed that the fluorophenyl portion in the organoselenium group is fundamental for the antidepressant-like action of this class of organochalcogens.
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Palladium‐Catalyzed Carbonylation of 2‐HaloSelenophenes: Synthesis of Selenophene‐2‐carboxamides, Selenophene‐2,5‐dicarboxamides and N,N′‐Bridged Selenophene‐2‐carboxamides
European Journal of Organic Chemistry, 2007Co-Authors: Patricia Prediger, Cristina W Nogueira, Ricardo Brandão, Gilson ZeniAbstract:We present herein our results on the palladium-catalyzed carbonylation of 2-haloSelenophene and amines, under carbon monoxide atmosphere, giving a new route to prepare Selenophene-2-carboxamides, Selenophene-2,5-dicarboxamides and N,N′-bridged Selenophene-2-carboxamides in good yields. The reaction proceeded cleanly under mild conditions, using a simple apparatus and procedure, and in the absence of high pressure of carbon monoxide. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
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Copper-Promoted Carbon−Nitrogen Bond Formation with 2-Iodo-Selenophene and Amides
The Journal of organic chemistry, 2006Co-Authors: Olga Soares Do Rego Barros, Cristina W Nogueira, Eluza Curte Stangherlin, Paulo H. Menezes, Gilson ZeniAbstract:We present here carbon−nitrogen bond formation via a coupling reaction of 2-iodo-Selenophene catalyzed by Cu(I) in the presence of a base and an inexpensive ligand, and establish the first route to obtaining 2-nitrogen-Selenophene derivatives in good yields. We can anticipate that this reaction works well with oxazolidinones, lactams, and aliphatic and aromatic amides, as nitrogen sources, in the absence of any supplementary additives. In addition, the reaction proceeded cleanly under mild reaction conditions and was sensitive to the ratio of amide/2-iodo-Selenophene, as well as the nature of the ligand, base, and solvent.
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copper promoted carbon nitrogen bond formation with 2 iodo Selenophene and amides
Journal of Organic Chemistry, 2006Co-Authors: Olga Soares Do Rego Barros, Cristina W Nogueira, Eluza Curte Stangherlin, Paulo H. Menezes, Gilson ZeniAbstract:We present here carbon−nitrogen bond formation via a coupling reaction of 2-iodo-Selenophene catalyzed by Cu(I) in the presence of a base and an inexpensive ligand, and establish the first route to obtaining 2-nitrogen-Selenophene derivatives in good yields. We can anticipate that this reaction works well with oxazolidinones, lactams, and aliphatic and aromatic amides, as nitrogen sources, in the absence of any supplementary additives. In addition, the reaction proceeded cleanly under mild reaction conditions and was sensitive to the ratio of amide/2-iodo-Selenophene, as well as the nature of the ligand, base, and solvent.
Henri Doucet - One of the best experts on this subject based on the ideXlab platform.
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Palladium-catalyzed successive C-H bond arylations and annulations toward the pi-extension of Selenophene-containing aromatic skeletons
Organic Chemistry Frontiers, 2019Co-Authors: Xinzhe Shi, Henri Doucet, Shuxin Mao, Thierry Roisnel, Jean-françois SouléAbstract:A modular approach for the synthesis of planar pi-extended selenium containing molecules from Selenophene has been developed. Different combinations of Pd-catalyzed desulfitative C-H bond arylations with (2-bromo)arylsulfonyl chlorides and Pd-catalyzed intra- or/and inter-molecular C-H bond arylations with aryl bromides allowed the extension of the Selenophene-containing aromatic skeleton at the [b]-, [c]- or [bd]-junctions to give phenanthro[b]Selenophenes, phenanthro[c]Selenophenes or diphenanthro[bd]Selenophenes.
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Palladium-catalyzed successive C–H bond arylations and annulations toward the π-extension of Selenophene-containing aromatic skeletons
Organic Chemistry Frontiers, 2019Co-Authors: Xinzhe Shi, Henri Doucet, Shuxin Mao, Thierry Roisnel, Jean-françois SouléAbstract:A modular approach for the synthesis of planar π-extended selenium containing molecules from Selenophene has been developed. Different combinations of Pd-catalyzed desulfitative C–H bond arylations with (2-bromo)arylsulfonyl chlorides and Pd-catalyzed intra- or/and inter-molecular C–H bond arylations with aryl bromides allowed the extension of the Selenophene-containing aromatic skeleton at the [b]-, [c]- or [b:d]-junctions to give phenanthro[b]Selenophenes, phenanthro[c]Selenophenes or diphenanthro[b:d]Selenophenes.
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Access to (Hetero)arylated Selenophenes via Palladium-catalysed Stille, Negishi or Suzuki Couplings or C−H Bond Functionalization Reaction
ChemCatChem, 2017Co-Authors: Aymen Skhiri, Jean-françois Soulé, Ridha Ben Salem, Henri DoucetAbstract:(Hetero)aryl-substituted Selenophenes exhibit important physical properties especially for optoelectronics. Palladium-catalysed coupling reactions currently represent the most efficient methods to prepare such (hetero)arylated Selenophene derivatives. Initially, Stille coupling was the most efficient reaction for the synthesis of these compounds; however, over the last decade, Suzuki coupling has become the most commonly employed. Recently, Pd-catalysed arylation via the C−H bond activation of Selenophenes has proved to be a very convenient alternative method for the preparation of several arylated Selenophenes as there is no need to prepare organometallic derivatives. In this Review, the progress and substrate scope in the synthesis of both C2- and C3-arylated Selenophenes via Pd-catalysis are summarized.
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Unprecedented Access to β-Arylated Selenophenes through Palladium-Catalysed Direct Arylation.
Chemistry (Weinheim an der Bergstrasse Germany), 2017Co-Authors: Aymen Skhiri, Jean-françois Soulé, Ridha Ben Salem, Henri DoucetAbstract:Several reported methods allow access to α-arylated Selenophenes, whereas the synthesis of β-arylated Selenophenes remains very challenging. Here, the Pd-catalysed coupling of benzenesulfonyl chlorides with Selenophenes affording regiospecific β-arylated Selenophenes is reported. The reaction proceeds with easily accessible catalyst, base and substrates, and tolerates a variety of substituents both on the benzene and Selenophene moieties. This transformation allows the programmed synthesis of polyarylated Selenophenes with potential applications in pharmaceutical and materials chemistry, as the installation of aryl groups at the desired positions can be achieved.
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Reactivity of bromoSelenophenes in palladium-catalyzed direct arylations
Beilstein Journal of Organic Chemistry, 2017Co-Authors: Aymen Skhiri, Ridha Ben Salem, Jean-françois Soulé, Henri DoucetAbstract:The reactivity of 2-bromo- and 2,5-dibromoSelenophenes in Pd-catalyzed direct heteroarylation was investigated. From 2-bromo-Selenophene, only the most reactive heteroarenes could be employed to prepare 2-heteroarylated Selenophenes; whereas, 2,5-dibromoSelenophene generally gave 2,5-di(heteroarylated) Selenophenes in high yields using both thiazole and thiophene derivatives. Moreover, sequential catalytic C2 heteroarylation, bromination, catalytic C5 arylation reactions allowed the synthesis of unsymmetrical 2,5-di(hetero)arylated Selenophene derivatives in three steps from Selenophene.
Cristina W Nogueira - One of the best experts on this subject based on the ideXlab platform.
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synthesis and antidepressant like activity of Selenophenes obtained via iron iii phseseph mediated cyclization of z selenoenynes
Organic and Biomolecular Chemistry, 2012Co-Authors: Bibiana M Gai, Andre L Stein, Juliano A Roehrs, Filipe N Bilheri, Cristina W Nogueira, Gilson ZeniAbstract:We present here the synthesis and antidepressant-like action of a series of 2,5-disubstituted-3-(organoseleno)-Selenophenes prepared by a novel synthetic route, the FeCl3–diorganyl dichalcogenide-mediated intramolecular cyclization of (Z)-chalcogenoenynes. The cyclized products were obtained in good yields. The results showed that 2c, 2d, 2e and 2o, evaluated in the mouse forced-swimming test, elicited an antidepressant-like activity. The studies clearly show that the phenyl group at the 2-position and an organoselenium group at the 3-position of the Selenophene ring are essential for the antidepressant-like activity of Selenophenes. A close inspection of the results also revealed that the fluorophenyl portion in the organoselenium group is fundamental for the antidepressant-like action of this class of organochalcogens.
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Palladium‐Catalyzed Carbonylation of 2‐HaloSelenophenes: Synthesis of Selenophene‐2‐carboxamides, Selenophene‐2,5‐dicarboxamides and N,N′‐Bridged Selenophene‐2‐carboxamides
European Journal of Organic Chemistry, 2007Co-Authors: Patricia Prediger, Cristina W Nogueira, Ricardo Brandão, Gilson ZeniAbstract:We present herein our results on the palladium-catalyzed carbonylation of 2-haloSelenophene and amines, under carbon monoxide atmosphere, giving a new route to prepare Selenophene-2-carboxamides, Selenophene-2,5-dicarboxamides and N,N′-bridged Selenophene-2-carboxamides in good yields. The reaction proceeded cleanly under mild conditions, using a simple apparatus and procedure, and in the absence of high pressure of carbon monoxide. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
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Copper-Promoted Carbon−Nitrogen Bond Formation with 2-Iodo-Selenophene and Amides
The Journal of organic chemistry, 2006Co-Authors: Olga Soares Do Rego Barros, Cristina W Nogueira, Eluza Curte Stangherlin, Paulo H. Menezes, Gilson ZeniAbstract:We present here carbon−nitrogen bond formation via a coupling reaction of 2-iodo-Selenophene catalyzed by Cu(I) in the presence of a base and an inexpensive ligand, and establish the first route to obtaining 2-nitrogen-Selenophene derivatives in good yields. We can anticipate that this reaction works well with oxazolidinones, lactams, and aliphatic and aromatic amides, as nitrogen sources, in the absence of any supplementary additives. In addition, the reaction proceeded cleanly under mild reaction conditions and was sensitive to the ratio of amide/2-iodo-Selenophene, as well as the nature of the ligand, base, and solvent.
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copper promoted carbon nitrogen bond formation with 2 iodo Selenophene and amides
Journal of Organic Chemistry, 2006Co-Authors: Olga Soares Do Rego Barros, Cristina W Nogueira, Eluza Curte Stangherlin, Paulo H. Menezes, Gilson ZeniAbstract:We present here carbon−nitrogen bond formation via a coupling reaction of 2-iodo-Selenophene catalyzed by Cu(I) in the presence of a base and an inexpensive ligand, and establish the first route to obtaining 2-nitrogen-Selenophene derivatives in good yields. We can anticipate that this reaction works well with oxazolidinones, lactams, and aliphatic and aromatic amides, as nitrogen sources, in the absence of any supplementary additives. In addition, the reaction proceeded cleanly under mild reaction conditions and was sensitive to the ratio of amide/2-iodo-Selenophene, as well as the nature of the ligand, base, and solvent.
Jean-françois Soulé - One of the best experts on this subject based on the ideXlab platform.
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Palladium-catalyzed successive C-H bond arylations and annulations toward the pi-extension of Selenophene-containing aromatic skeletons
Organic Chemistry Frontiers, 2019Co-Authors: Xinzhe Shi, Henri Doucet, Shuxin Mao, Thierry Roisnel, Jean-françois SouléAbstract:A modular approach for the synthesis of planar pi-extended selenium containing molecules from Selenophene has been developed. Different combinations of Pd-catalyzed desulfitative C-H bond arylations with (2-bromo)arylsulfonyl chlorides and Pd-catalyzed intra- or/and inter-molecular C-H bond arylations with aryl bromides allowed the extension of the Selenophene-containing aromatic skeleton at the [b]-, [c]- or [bd]-junctions to give phenanthro[b]Selenophenes, phenanthro[c]Selenophenes or diphenanthro[bd]Selenophenes.
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Palladium-catalyzed successive C–H bond arylations and annulations toward the π-extension of Selenophene-containing aromatic skeletons
Organic Chemistry Frontiers, 2019Co-Authors: Xinzhe Shi, Henri Doucet, Shuxin Mao, Thierry Roisnel, Jean-françois SouléAbstract:A modular approach for the synthesis of planar π-extended selenium containing molecules from Selenophene has been developed. Different combinations of Pd-catalyzed desulfitative C–H bond arylations with (2-bromo)arylsulfonyl chlorides and Pd-catalyzed intra- or/and inter-molecular C–H bond arylations with aryl bromides allowed the extension of the Selenophene-containing aromatic skeleton at the [b]-, [c]- or [b:d]-junctions to give phenanthro[b]Selenophenes, phenanthro[c]Selenophenes or diphenanthro[b:d]Selenophenes.
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Access to (Hetero)arylated Selenophenes via Palladium-catalysed Stille, Negishi or Suzuki Couplings or C−H Bond Functionalization Reaction
ChemCatChem, 2017Co-Authors: Aymen Skhiri, Jean-françois Soulé, Ridha Ben Salem, Henri DoucetAbstract:(Hetero)aryl-substituted Selenophenes exhibit important physical properties especially for optoelectronics. Palladium-catalysed coupling reactions currently represent the most efficient methods to prepare such (hetero)arylated Selenophene derivatives. Initially, Stille coupling was the most efficient reaction for the synthesis of these compounds; however, over the last decade, Suzuki coupling has become the most commonly employed. Recently, Pd-catalysed arylation via the C−H bond activation of Selenophenes has proved to be a very convenient alternative method for the preparation of several arylated Selenophenes as there is no need to prepare organometallic derivatives. In this Review, the progress and substrate scope in the synthesis of both C2- and C3-arylated Selenophenes via Pd-catalysis are summarized.
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Unprecedented Access to β-Arylated Selenophenes through Palladium-Catalysed Direct Arylation.
Chemistry (Weinheim an der Bergstrasse Germany), 2017Co-Authors: Aymen Skhiri, Jean-françois Soulé, Ridha Ben Salem, Henri DoucetAbstract:Several reported methods allow access to α-arylated Selenophenes, whereas the synthesis of β-arylated Selenophenes remains very challenging. Here, the Pd-catalysed coupling of benzenesulfonyl chlorides with Selenophenes affording regiospecific β-arylated Selenophenes is reported. The reaction proceeds with easily accessible catalyst, base and substrates, and tolerates a variety of substituents both on the benzene and Selenophene moieties. This transformation allows the programmed synthesis of polyarylated Selenophenes with potential applications in pharmaceutical and materials chemistry, as the installation of aryl groups at the desired positions can be achieved.
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Reactivity of bromoSelenophenes in palladium-catalyzed direct arylations
Beilstein Journal of Organic Chemistry, 2017Co-Authors: Aymen Skhiri, Ridha Ben Salem, Jean-françois Soulé, Henri DoucetAbstract:The reactivity of 2-bromo- and 2,5-dibromoSelenophenes in Pd-catalyzed direct heteroarylation was investigated. From 2-bromo-Selenophene, only the most reactive heteroarenes could be employed to prepare 2-heteroarylated Selenophenes; whereas, 2,5-dibromoSelenophene generally gave 2,5-di(heteroarylated) Selenophenes in high yields using both thiazole and thiophene derivatives. Moreover, sequential catalytic C2 heteroarylation, bromination, catalytic C5 arylation reactions allowed the synthesis of unsymmetrical 2,5-di(hetero)arylated Selenophene derivatives in three steps from Selenophene.
Ahmed Iraqi - One of the best experts on this subject based on the ideXlab platform.
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Selenophene vs thiophene in benzothiadiazole based low energy gap donor acceptor polymers for photovoltaic applications
Journal of Materials Chemistry, 2013Co-Authors: Abdulaziz Ali Alghamdi, Darren C Watters, Solyman Alfaifi, Mohammed S Almeataq, David M Coles, James Kingsley, David G Lidzey, Ahmed IraqiAbstract:A series of low energy gap polymers comprising 2,7-linked carbazole or fluorene units flanked by thiophene or Selenophene repeat units as alternating donor units and benzothiadiazole with or without alkoxy substituents as alternating acceptor repeat units is reported. The effects of replacing thiophene with Selenophene in this series of polymers on their optical, electrochemical and photovoltaic device performance when fabricated into bulk heterojunction solar cells using PC70BM as an acceptor are investigated. Power conversion efficiencies (PCEs) ranging from 3.34 to 5.41% are obtained with these systems. Thiophene-based polymers are found to have higher efficiency compared to comparable Selenophene-based polymers. We tentatively explain such differences on the basis of reduced molar absorbance and reduced charge-carrier mobility in the Selenophene-based polymers.
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Selenophene vs. thiophene in benzothiadiazole-based low energy gap donor–acceptor polymers for photovoltaic applications
Journal of Materials Chemistry A, 2013Co-Authors: Abdulaziz Ali Alghamdi, Darren C Watters, Mohammed S Almeataq, David M Coles, James Kingsley, David G Lidzey, Solyman Al-faifi, Ahmed IraqiAbstract:A series of low energy gap polymers comprising 2,7-linked carbazole or fluorene units flanked by thiophene or Selenophene repeat units as alternating donor units and benzothiadiazole with or without alkoxy substituents as alternating acceptor repeat units is reported. The effects of replacing thiophene with Selenophene in this series of polymers on their optical, electrochemical and photovoltaic device performance when fabricated into bulk heterojunction solar cells using PC70BM as an acceptor are investigated. Power conversion efficiencies (PCEs) ranging from 3.34 to 5.41% are obtained with these systems. Thiophene-based polymers are found to have higher efficiency compared to comparable Selenophene-based polymers. We tentatively explain such differences on the basis of reduced molar absorbance and reduced charge-carrier mobility in the Selenophene-based polymers.