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Habib Nasri - One of the best experts on this subject based on the ideXlab platform.
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Effect of the coordination of π-acceptor 4-Cyanopyridine ligand on the structural and electronic properties of meso-tetra(para-methoxy) and meso-tetra(para-chlorophenyl) porphyrin cobalt(II) coordination compounds. Application in the catalytic degrad
RSC Advances, 2020Co-Authors: Mouhieddinne Guergueb, Ilona Turowska-tyrk, Soumaya Nasri, Jihed Brahmi, Frédérique Loiseau, Florian Molton, Thierry Roisnel, Vincent Guérineau, Kaïss Aouadi, Habib NasriAbstract:To examine the influence of both the important π-acceptor character of the 4-Cyanopyridine ligand and the nature of the para-substituted phenyls of meso-porphyrins on the electronic, electrochemical and structural properties of cobaltous metalloporphyrins, we prepared and fully characterized two coordination compounds: the (4-Cyanopyridine)[meso-tetra(para-methoxyphenyl)porphyrinato]cobalt(II) and the (4-Cyanopyridine)[meso-tetra(para-chlorophenyl)porphyrinato]cobalt(II) with the [CoII(TMPP)(4-CNpy)] and [CoII(TClPP)(4-CNpy)] formulas (complexes 1–2). The solution structures of compounds 1–2 were confirmed by 1H NMR spectroscopy and mass spectrometry methods. They were further characterized by cyclic voltammetry and photoluminescence studies. The X-ray molecular structure data show that the Co-TClPP-4-NCpy derivative (2) exhibits high ruffling deformation compared to that of the Co-TMPP-4-CNpy species (1). Notably, the crystal packing of complex 1 shows the formation of Co⋯Co supramolecular dimers with a distance of 5.663 A. As an application of our two cobaltous compounds, an investigation involving complexes 1–2 in the degradation of the methylene blue dye in the presence and absence of H2O2 in aqueous solutions was carried out. These promising results show that 1–2 can be used as catalysts in the degradation processes of dyes.
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New insights on the electronic, magnetic, electric and molecular structure of a bis-(4-Cyanopyridine) iron(III) complex with the meso-tetrakis(4-methoxyphenyl)porphyrin
Inorganica Chimica Acta, 2019Co-Authors: Leila Ben Haj Hassen, Selma Dhifaoui, Yoann Rousselin, Valérie Marvaud, Christine Stern, Charles E. Schulz, Habib NasriAbstract:We have successfully synthesized and characterized a new low-spin iron(III) bis(4-Cyanopyridine) complex with a meso-porphyrin substituted in the para positions of the phenyls by the methoxy group, namely the bis(4-Cyanopyridine)[(meso-tetrakis(4-metoxyphenylporphyrinato)]iron(III) trifluoromethanesulfonate chlorobenzene monosolvate complex with the formula [FeIII(TMPP)(4-CNpy)2]SO3CF3.C6H5Cl (I). This species was characterized through ultraviolet–visible, Fourier-transform infrared and Mossbauer spectroscopy as well as by SQUID magnetometry, cyclic voltammetry, and X-ray crystallography. These characterizations indicated that our synthetic heme model is a low-spin (S = 1/2) coordination compound and especially shows that the structural, electronic and the magnetic properties of complex (I) are closely dominated by the presence of the methoxy σ-donor group at the para positions of the meso-porphyrin.
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Crystal structure of (4-Cyanopyridine-κN){5,10,15,20-tetrakis[4-(benzoyloxy)phenyl]porphyrinato-κ4N}zinc–4-Cyanopyridine (1/1)
International Union of Crystallography, 2016Co-Authors: Soumaya Nasri, Ilona Turowska-tyrk, Nesrine Amiri, Jean-claude Daran, Habib NasriAbstract:In the title compound, [Zn(C72H44N4O8)(C6H4N2)]·C6H4N2 or [Zn(TPBP)(4-CNpy]·(4-CNpy) [where TPBP and 4-CNpy are 5,10,15,20-(tetraphenylbenzoate)porphyrinate and 4-Cyanopyridine, respectively], the ZnII cation is chelated by four pyrrole-N atoms of the porphyrinate anion and coordinated by a pyridyl-N atom of the 4-CNpy axial ligand in a distorted square-pyramidal geometry. The average Zn—N(pyrrole) bond length is 2.060 (6) Å and the Zn—N(4-CNpy) bond length is 2.159 (2) Å. The zinc cation is displaced by 0.319 (1) Å from the N4C20 mean plane of the porphyrinate anion toward the 4-Cyanopyridine axial ligand. This porphyrinate macrocycle exhibits major saddle and moderate ruffling and doming deformations. In the crystal, the [Zn(TPBP)(4-CNpy)] complex molecules are linked together via weak C—H...N, C—H...O and C—H...π interactions, forming supramolecular channels parallel to the c axis. The non-coordinating 4-Cyanopyridine molecules are located in the channels and linked with the complex molecules, via weak C—H...N interactions and π-π stacking or via weak C—H...O and C—H...π interactions. The non-coordinating 4-Cyanopyridine molecule is disordered over two positions with an occupancy ratio of 0.666 (4):0.334 (4)
Maria Cantarella - One of the best experts on this subject based on the ideXlab platform.
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high yield continuous production of nicotinic acid via nitrile hydratase amidase cascade reactions using cascade csmrs
Enzyme and Microbial Technology, 2011Co-Authors: Laura Cantarella, Alberto Gallifuoco, Anna Malandra, Ludmila Martinkova, Agata Spera, Maria CantarellaAbstract:High yields of nicotinic acid from 3-Cyanopyridine bioconversion were obtained by exploiting the in situ nitrile hydratase-amidase enzymatic cascade system of Microbacterium imperiale CBS 498-74. Experiments were carried out in continuously stirred tank UF-membrane bioreactors (CSMRs) arranged in series. This reactor configuration enables both enzymes, involved in the cascade reaction, to work with optimized kinetics, without any purification, exploiting their differing temperature dependences. To this end, the first CSMR, optimized for the properties of the NHase, was operated (i) at low temperature (5°C), limiting inactivation of the more fragile enzyme, nitrile hydratase, (ii) with a high residence time (24 h) to overcome reaction rate limitation. The second CSMR, optimized for the properties of the AMase, was operated (i) at a higher temperature (50°C), (ii) with a lower residence time (6h), and (iii) with a lower substrate (3-Cyanopyridine) concentration to control excess substrate inhibition. The appropriate choice of operational conditions enabled total conversion of 3-cyanpyridine (up to 200 mM) into nicotinic acid to be achieved at steady-state and for long periods. Higher substrate concentrations required two CSMRs optimized for the properties of the NHase arranged in series to drive the first reaction to completion.
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application of continuous stirred membrane reactor to 3 Cyanopyridine bioconversion using the nitrile hydratase amidase cascade system of microbacterium imperiale cbs 498 74
Enzyme and Microbial Technology, 2010Co-Authors: Laura Cantarella, Alberto Gallifuoco, Anna Malandra, Ludmila Martinkova, Fabrizia Pasquarelli, Agata Spera, Maria CantarellaAbstract:Abstract The bioconversion of 3-Cyanopyridine using the in situ nitrile hydratase–amidase cascade system of resting Microbacterium imperiale CBS 498-74 cells was investigated in an ultrafiltration-membrane reactor, operated in either batch or continuous mode. The effects of operating conditions such as the amount of biocatalyst, substrate concentration, substrate feeding rate, mean residence time, and enzyme-to-substrate ratio, were investigated with the aim of achieving almost 100% substrate conversion and high reactor productivity. As a result, it was found that the NHase–AMase cascade system could be adequately exploited in a continuous reactor configuration. The differing temperature dependence of nitrile hydratase and amidase kinetics enabled the operational parameters to be module d to ensure (i) nitrile hydratase operational stability (at 5 °C), and (ii) 100% conversion of 3-Cyanopyridine into nicotinic acid, or, alternatively, (iii) enrichment of the effluent stream with the intermediate nicotinamide (up to 80% conversion). It was possible to select operating conditions that allowed long periods of operation (at least 100 h) at a constant flow-rate without enzyme activity loss.
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purification and characterization of a nitrilase from fusarium solani o1
Journal of Molecular Catalysis B-enzymatic, 2008Co-Authors: Vojtěch Vejvoda, Ondřej Kaplan, Maria Cantarella, Karel Bezouska, Petr Pompach, Miroslav Sulc, Oldřich BenadaAbstract:Abstract An intracellular nitrilase was purified from a Fusarium solani O1 culture, in which the enzyme (up to 3000 U L −1 ) was induced by 2-Cyanopyridine. SDS-PAGE revealed one major band corresponding to a molecular weight of approximately 40 kDa. Peptide mass fingerprinting suggested a high similarity of the protein with the putative nitrilase from Gibberella moniliformis . Electron microscopy revealed that the enzyme molecules associated into extended rods. The enzyme showed high specific activities towards benzonitrile (156 U mg −1 ) and 4-Cyanopyridine (203 U mg −1 ). Other aromatic nitriles (3-chlorobenzonitrile, 3-hydroxybenzonitrile) also served as good substrates for the enzyme. The rates of hydrolysis of aliphatic nitriles (methacrylonitrile, propionitrile, butyronitrile, valeronitrile) were 14–26% of that of benzonitrile. The nitrilase was active within pH 5–10 and at up to 50 °C with optima at pH 8.0 and 40–45 °C. Its activity was strongly inhibited by Hg 2+ and Ag + ions. More than half of the enzyme activity was preserved at up to 50% of n -hexane or n -heptane or at up to 15% of xylene or ethanol. Operational stability of the enzyme was examined by the conversion of 45 mM 4-Cyanopyridine in a continuous and stirred ultrafiltration-membrane reactor. The nitrilase half-life was 277 and 10.5 h at 35 and 45 °C, respectively.
L A Rodinovskaya - One of the best experts on this subject based on the ideXlab platform.
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one pot synthesis of diverse 4 di tri fluoromethyl 3 Cyanopyridine 2 1h thiones and their utilities in the cascade synthesis of annulated heterocycles
ACS Combinatorial Science, 2008Co-Authors: L A Rodinovskaya, A M Shestopalov, Anna V Gromova, Alexander A ShestopalovAbstract:Diverse substituted 4-di(tri)fluoromethyl-3-Cyanopyridine-2(1H)-thiones were synthesized via the Claisen condensation of alpha-methyl(methylene)ketones with di(tri)fluoroacetate, followed by the immediate Thorpe-Guareschi reaction of the preformed di(tri)fluoromethyl-1,3-diketones with cyanothioacetamide. The procedure allows facile synthesis of the di(tri)flouromethylated pyridine-2(1H)-thiones in 50-95% yields, without the need for isolation and purification of intermediates. Resultant 4-di(tri)fluoromethyl-3-Cyanopyridine-2(1 H)-thiones were subsequently utilized in domino reactions to produce first various substituted thieno[2,3-b]pyridines and, then, thienopyridines polyannulated with pyridine, pyrimidine, benzodiazocine, diazepine, and pyran rings.
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one pot synthesis of 4 6 diaryl 3 Cyanopyridine 2 1h thiones and their transformation to substituted thieno 2 3 b 4 5 b dipyridines and pyrido 3 2 4 5 thieno 3 2 d pyrimidines
Russian Chemical Bulletin, 2003Co-Authors: A M Shestopalov, Anna V Gromova, K G Nikishin, L A RodinovskayaAbstract:4,6-Diaryl-3-Cyanopyridine-2(1H)-thiones were synthesized in one step by the reaction of elemental sulfur, malononitrile, and 2-aryl-1-aroylethylenes in the presence of excess triethylamine. The products were used in one-pot syntheses of substituted thieno[2,3-b;4,5-b]dipyridines and pyrido[3",2":4,5]thieno[3,2-d]pyrimidines.
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advances in the chemistry of 3 cyanopyridin 2 1h ones thiones and selenones
Sulfur Reports, 1992Co-Authors: V P Litvinov, L A Rodinovskaya, Yu A Sharanin, A M Shestopalov, A SenningAbstract:Abstract This review is concerned with the synthesis, structure, physico-chemical properties and reactivity of 3-cyanopyridin-2(1H)-ones, -thiones, and -selenones and their derivatives. The 3-cyanopyridin-2(1H)-ones, -thiones, and -selenones being bifunctional compounds containing nitrile and amide, thioamide, or selenoamide groups with an endocyclic nitrogen atom are widely used in the synthesis of different classes of annelated heterocycles possessing practically important properties.
Xu Cheng - One of the best experts on this subject based on the ideXlab platform.
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lewis acid catalyzed selective reductive decarboxylative pyridylation of n hydroxyphthalimide esters synthesis of congested pyridine substituted quaternary carbons
ACS Catalysis, 2019Co-Authors: Liuzhou Gao, Jia Cao, Guoqiang Wang, Hui Chen, Xueting Liu, Xu ChengAbstract:A practical and efficient Lewis acid-catalyzed radical–radical coupling reaction of N-hydroxyphthalimide esters and 4-Cyanopyridines with inexpensive bis(pinacolato)diboron as reductant has been de...
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Perfluoroalkylative pyridylation of alkenes via 4-Cyanopyridine-boryl radicals
Chemical science, 2019Co-Authors: Jia Cao, Guoqiang Wang, Liuzhou Gao, Hui Chen, Xueting Liu, Xu ChengAbstract:A metal-free and photo-free method for the perfluoroalkylative pyridylation of alkenes has been developed via a combination of computational and experimental studies. Density functional theory calculations and control experiments indicate that the homolysis of Rf−X (X = Br, I) bonds by the 4-Cyanopyridine-boryl radicals in situ generated from 4-Cyanopyridine and B2pin2 is the key step. Sequential addition of Rf radicals to alkenes and the selective cross-coupling of the resulting alkyl radicals and 4-Cyanopyridine-boryl radicals gives alkene difunctionalization products with a quaternary carbon center. This method exhibits a broad substrate scope and good functional group compatibility.
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metal free synthesis of c 4 substituted pyridine derivatives using pyridine boryl radicals via a radical addition coupling mechanism a combined computational and experimental study
Journal of the American Chemical Society, 2017Co-Authors: Guoqiang Wang, Jia Cao, Liuzhou Gao, Xu Cheng, Wenxin Chen, Wenhao HuangAbstract:Density functional theory investigations revealed that the pyridine-boryl radical generated in situ using 4-Cyanopyridine and bis(pinacolato)diboron could be used as a bifunctional “reagent”, which serves as not only a pyridine precursor but also a boryl radical. With the unique reactivity of such radicals, 4-substituted pyridine derivatives could be synthesized using α,β-unsaturated ketones and 4-Cyanopyridine via a novel radical addition/C—C coupling mechanism. Several controlled experiments were conducted to provide supportive evidence for the proposed mechanism. In addition to enones, the scope could be extended to a wide range of boryl radical acceptors, including various aldehydes and ketones, aryl imines and alkynones. Lastly, this transformation was applied in the late-stage modification of a complicated pharmaceutical molecule.
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Metal-Free Synthesis of C‑4 Substituted Pyridine Derivatives Using Pyridine-boryl Radicals via a Radical Addition/Coupling Mechanism: A Combined Computational and Experimental Study
2017Co-Authors: Guoqiang Wang, Jia Cao, Liuzhou Gao, Wenxin Chen, Wenhao Huang, Xu ChengAbstract:Density functional theory investigations revealed that the pyridine-boryl radical generated in situ using 4-Cyanopyridine and bis(pinacolato)diboron could be used as a bifunctional “reagent”, which serves as not only a pyridine precursor but also a boryl radical. With the unique reactivity of such radicals, 4-substituted pyridine derivatives could be synthesized using α,β-unsaturated ketones and 4-Cyanopyridine via a novel radical addition/CC coupling mechanism. Several controlled experiments were conducted to provide supportive evidence for the proposed mechanism. In addition to enones, the scope could be extended to a wide range of boryl radical acceptors, including various aldehydes and ketones, aryl imines and alkynones. Lastly, this transformation was applied in the late-stage modification of a complicated pharmaceutical molecule
A M Shestopalov - One of the best experts on this subject based on the ideXlab platform.
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one pot synthesis of diverse 4 di tri fluoromethyl 3 Cyanopyridine 2 1h thiones and their utilities in the cascade synthesis of annulated heterocycles
ACS Combinatorial Science, 2008Co-Authors: L A Rodinovskaya, A M Shestopalov, Anna V Gromova, Alexander A ShestopalovAbstract:Diverse substituted 4-di(tri)fluoromethyl-3-Cyanopyridine-2(1H)-thiones were synthesized via the Claisen condensation of alpha-methyl(methylene)ketones with di(tri)fluoroacetate, followed by the immediate Thorpe-Guareschi reaction of the preformed di(tri)fluoromethyl-1,3-diketones with cyanothioacetamide. The procedure allows facile synthesis of the di(tri)flouromethylated pyridine-2(1H)-thiones in 50-95% yields, without the need for isolation and purification of intermediates. Resultant 4-di(tri)fluoromethyl-3-Cyanopyridine-2(1 H)-thiones were subsequently utilized in domino reactions to produce first various substituted thieno[2,3-b]pyridines and, then, thienopyridines polyannulated with pyridine, pyrimidine, benzodiazocine, diazepine, and pyran rings.
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reactions of n 2 chloroacetyl α amino acids with 3 Cyanopyridine 2 1h thiones new promising route to 3 4 dihydropyrido 3 2 4 5 thieno 3 2 e 1 4 diazepine 2 1h 5 diones
Russian Chemical Bulletin, 2003Co-Authors: A E Fedorov, A M Shestopalov, Pavel A BelyakovAbstract:The reactions of N-(2-chloroacetyl)-α-amino acids with 3-Cyanopyridine-2(1H)-thiones afforded N-(3-aminothieno[2,3-b]pyridin-2-ylcarbonyl)-α-amino acids. Heating of the latter smoothly produced 3,4-dihydropyrido[3",2":4,5]thieno[3,2-e][1,4]diazepine-2(1H),5-diones in high yields.
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one pot synthesis of 4 6 diaryl 3 Cyanopyridine 2 1h thiones and their transformation to substituted thieno 2 3 b 4 5 b dipyridines and pyrido 3 2 4 5 thieno 3 2 d pyrimidines
Russian Chemical Bulletin, 2003Co-Authors: A M Shestopalov, Anna V Gromova, K G Nikishin, L A RodinovskayaAbstract:4,6-Diaryl-3-Cyanopyridine-2(1H)-thiones were synthesized in one step by the reaction of elemental sulfur, malononitrile, and 2-aryl-1-aroylethylenes in the presence of excess triethylamine. The products were used in one-pot syntheses of substituted thieno[2,3-b;4,5-b]dipyridines and pyrido[3",2":4,5]thieno[3,2-d]pyrimidines.
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advances in the chemistry of 3 cyanopyridin 2 1h ones thiones and selenones
Sulfur Reports, 1992Co-Authors: V P Litvinov, L A Rodinovskaya, Yu A Sharanin, A M Shestopalov, A SenningAbstract:Abstract This review is concerned with the synthesis, structure, physico-chemical properties and reactivity of 3-cyanopyridin-2(1H)-ones, -thiones, and -selenones and their derivatives. The 3-cyanopyridin-2(1H)-ones, -thiones, and -selenones being bifunctional compounds containing nitrile and amide, thioamide, or selenoamide groups with an endocyclic nitrogen atom are widely used in the synthesis of different classes of annelated heterocycles possessing practically important properties.
