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Pierre Vogel - One of the best experts on this subject based on the ideXlab platform.
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Conformational analysis of α-methoxyketones. A photoelectron spectroscopic investigation of 3-methoxybicyclo[2.2.1]Heptan-2-Ones.
Tetrahedron, 1992Co-Authors: Janine Cossy, Pierre-alain Carrupt, Jean-pierre Pete, Rolf Gleiter, Alexander Flatow, Pierre VogelAbstract:The photoelectron spectra of 3-endo-(2), of 3-exo-methoxybicyclo[2.2.1]Heptan-2-One (3) and of 2-endo,3-endo-dimethoxybicyclo[2.2.1]heptane (4) are analyzed in comparison with data reported for other analogous systems and with predictions based on quantum mechanical calculations. In 2, the ''homo-gauche'' conformer (2G) is more stable than the ''homo-anti'' conformer (2A) whereas in 3, the ''homo-anti'' conformer (3A) is slightly more stable than the corresponding ''homo-gauche'' rotamer (3G).
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Enantiomerically pure 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives (naked sugars) as synthetic intermediates. 18. Synthesis of .alpha.-(1.fwdarw.2)-, .alpha.-(1.fwdarw.3)-, .alpha.-(1.fwdarw.4)-, and .alpha.-(1.fwdarw.5)-C-linked disaccharides throu
The Journal of Organic Chemistry, 1992Co-Authors: R. Mampuya Bimwala, Pierre VogelAbstract:The ''naked sugar'' (+)-1 (1R,2S,4R)-2-cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl (1S')-camphanate) has been converted into (+)-(1R,4R,5R,6R)-3-methylidene-5-exo,6-exo(isopropylidenedioxy)-7-oxabi cyclo[2.2.1]Heptan-2-One ((+)-3) and (-)-(1S,4R,5R,6R)-5-exo-(benzeneselenyl)-6-endo-chloro-3-methylidene-7-o xabicyclo[2.2.1]Heptan-2-One ((-)-26). Reductive addition of 2,3,4,6-tetra-O-acetylglucopyranosyl radical onto (+)-3 and (-)-26 were highly stereoselective giving exclusively 3-endo-(glucosylmethyl)-7-oxabicyclo[2.2.1]Heptan-2-One derivatives. The anomeric selectivity (alpha-C-glucoside vs beta-C-glucoside) was 5.5:1 with (+)-3 and 8:1 with (-)-26. The C-glucosides so-obtained were transformed into alpha-(1 --> 2)-, alpha-(1 --> 3)-, alpha-(1 --> 4)-, and alpha-(1 --> 5)-C-linked disaccharide derivatives which combine alpha-D-glucopyranose with L-altro-hexonolactone, L-manno-hexonolactone, L-mannose, and L-(talo-hexofuranosid)uronic acid, respectively.
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Substituent effects on the regioselectivity of the baeyer-villiger oxidation of 7-oxabicyclo[2.2.1]Heptan-2-Ones
Tetrahedron, 1992Co-Authors: Geza Arvai, Fattori Daniela, Pierre VogelAbstract:New 3-oxy substituted and 3,6-dioxydisubstituted 7-oxabicyclo[2.2.1]Heptan-2-Ones have been prepared. The regioselectivity of their Baeyer-Villiger oxidation has been determined and compared with that of other 7-oxabicyclo[2.2.1[Heptan-2-One derivatives. If the substituent at C(3-exo) is an O-acyl or another group less electron-releasing, the bridgehead C(1) migration is favoured, leading to 2,8-dioxa-bicyclo[3.2.1]octan-3-ones. When the substituent at C(3) is a MeO or (tBu)Me2SiO group, the Baeyer-Villiger oxidation leads to 3,8-dioxabicyclo[3.2.1]octan-2-ones due to preferred C(3) migration. The latter regioselectivity is higher for 3-endo-MeO than for 3-exo-MeO substituted ketones and it can be enhanced by remote oxy substituents at the C(6-endo) position.
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Highly Stereoselective Aminohydroxylations of exo-2-Cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl Acetate
Synthesis, 1991Co-Authors: Susy Allemann, Pierre VogelAbstract:Protected forms of exo-5-amino-exo-6-hydroxy-7-oxabicyclo [2.2.1]Heptan-2-One and of exo-5-amino-endo-6-hydroxy-7-oxabicyclo[2.2.1]Heptan-2-One can be obtained readily and with high stereoselectivity from exo-2-cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl acetate (+/-)-(7). The processes involve acid promoted rearrangements of N-carbonyl aziridines 10 [(1RS,2SR,4RS,5RS, 6SR)-6-cyano-8-oxa-3-azatricyclo[3.2.10(2,4)]oct-6-yl acetate derivatives] derived from (+/-)-7.
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Substituent effects on the regioselectivity of one-carbon ring expansions of 7-oxabicyclo[2.2.1]Heptan-2-One derivatives with diazomethane
Tetrahedron Letters, 1991Co-Authors: Yves Auberson, R. Mampuya Bimwala, Pierre VogelAbstract:Reactions of CH2N2 with 5-exo,6-exo-isopropylidenedioxy-7-oxabicyclo[2.2.1]Heptan-2-One and 3-substituted derivatives have been studied. The regioselectivity of the one-carbon ring enlargement process depends on the nature of the substituent at C(3) and on its relative configuration.
F W B Einstein - One of the best experts on this subject based on the ideXlab platform.
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2 chlorobicyclo 2 2 1 hept 5 ene 2 carboxamide and 2 chlorobicyclo 2 2 1 heptane 2 carboxamide as precursors of bicyclo 2 2 1 hept 5 en 2 one and bicyclo 2 2 1 heptan 2 one resolution absolute configuration and hydrogen bonding properties
Tetrahedron-asymmetry, 2005Co-Authors: Erika Plettner, Ashley Mohle, Martin T Mwangi, Johanna Griscti, Brian O Patrick, Ranjeet Nair, Raymond J Batchelor, F W B EinsteinAbstract:The absolute configuration of bicyclo[2.2.1]Heptan-2-One has not been correlated with a crystal structure of a chemical precursor. The only chemical correlation available had an ambiguity, which could have reversed the assignment. Herein, we report the resolution of 2-chlorobicyclo[2.2.1]hept-5-en-2-exo-carboxamide on a cellulose triacetate column and the crystal structures of the enantiomerically pure and racemic α-chloroamide. We found the absolute configuration (1R,2R,4R) for the (+)-enantiomer of the α-chloroamide. This compound was converted to (+)-bicyclo[2.2.1]hept-5-ene-2-one by base hydrolysis, and the 5,6-unsaturated compounds converted to the saturated congeners. This is the first unambiguous experimental determination of the absolute configuration of bicyclo[2.2.1]Heptan-2-One and of bicyclo[2.2.1]hept-5-ene-2-one. The three crystal structures of 2-chlorobicyclo[2.2.1]hept-5-en-2-exo-carboxamide reported herein reveal H-bonded dimers, with two distinct orientations of the bicyclic portion relative to the carboxamide dimer. In the racemic crystal, each dimer is composed of two enantiomers, and the bicyclic portions have their bridge carbon atom (C-7) on opposite sides of the H-bonded carboxamide dimer moiety. In the enantiomerically pure crystals, the major dimer had both C-7 atoms on the same side of the carboxamide dimer moiety while the minor dimer had the C-7 atoms on opposite sides. The dimers are present in solution, and can be easily monitored.
Dominque Wolbert - One of the best experts on this subject based on the ideXlab platform.
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integrated process for the removal of indoor vocs from food industry manufacturing elimination of butane 2 3 dione and heptan 2 one by cold plasma photocatalysis combination
Journal of Photochemistry and Photobiology A-chemistry, 2020Co-Authors: Wala Abou Saoud, Aymen Amine Assadi, Abdoulaye Kane, Audevalerie Jung, Pierre Le Cann, Anne Gerard, Frederic Bazantay, Abdelkrim Bouzaza, Dominque WolbertAbstract:Abstract Coupling Non-thermal plasma (dielectric barrier discharge) with photocatalysis (TiO2-/UV) can be a promising technique to improve indoor air quality. In this study, Butane-2,3-dione and Heptan-2-One, usually found in food industry, were used as target compounds. Firstly, each pollutant was studied alone by photocatalytic treatment under experimental parameter effects like gases flow rate, VOCs inlet concentration, and humidity levels. Otherwise, in order to understand pollutants reaction mechanisms, a complex composition mixture was then studied and discussed. Experiments with dry and wet air showed good Heptan-2-One removal but negatively affected Butane-2,3-dione elimination rate. The Butane-2,3-dione/Heptan-2-One oxidation study was carried out by cold plasma-photocatalysis combination in the same pilot reactor. Excellent treatment yields were observed in terms of pollutant removal efficiency, mineralization and Ozone decomposition. Additionally, intermediate by-product exhausts from three technologies e.g. TiO2/UV-light system, DBD-plasma and their combination are identified.
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Integrated process for the removal of indoor VOCs from food industry manufacturing Elimination of Butane-2,3-dione and Heptan-2-One by cold plasma-photocatalysis combination
Journal of Photochemistry and Photobiology A: Chemistry, 2020Co-Authors: W. Abou Saoud, Aymen Amine Assadi, Abdoulaye Kane, Anne Gerard, Frederic Bazantay, Abdelkrim Bouzaza, A.-v. Jung, Pierre Le Cann, Dominque WolbertAbstract:Coupling Non-thermal plasma (dielectric barrier discharge) with photocatalysis (TiO2-/UV) can be a promising technique to improve indoor air quality. In this study, Butane-2,3-dione and Heptan-2-One, usually found in food industry, were used as target compounds. Firstly, each pollutant was studied alone by photocatalytic treatment under experimental parameter effects like gases flow rate, VOCs inlet concentration, and humidity levels. Otherwise, in order to understand pollutants reaction mechanisms, a complex composition mixture was then studied and discussed. Experiments with dry and wet air showed good Heptan-2-One removal but negatively affected Butane-2,3-dione elimination rate. The Butane-2,3-dione/Heptan-2-One oxidation study was carried out by cold plasma-photocatalysis combination in the same pilot reactor. Excellent treatment yields were observed in terms of pollutant removal efficiency, mineralization and Ozone decomposition. Additionally, intermediate by-product exhausts from three technologies e.g. TiO2/UV-light system, DBD-plasma and their combination are identified.
R. Mampuya Bimwala - One of the best experts on this subject based on the ideXlab platform.
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Enantiomerically pure 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives (naked sugars) as synthetic intermediates. 18. Synthesis of .alpha.-(1.fwdarw.2)-, .alpha.-(1.fwdarw.3)-, .alpha.-(1.fwdarw.4)-, and .alpha.-(1.fwdarw.5)-C-linked disaccharides throu
The Journal of Organic Chemistry, 1992Co-Authors: R. Mampuya Bimwala, Pierre VogelAbstract:The ''naked sugar'' (+)-1 (1R,2S,4R)-2-cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl (1S')-camphanate) has been converted into (+)-(1R,4R,5R,6R)-3-methylidene-5-exo,6-exo(isopropylidenedioxy)-7-oxabi cyclo[2.2.1]Heptan-2-One ((+)-3) and (-)-(1S,4R,5R,6R)-5-exo-(benzeneselenyl)-6-endo-chloro-3-methylidene-7-o xabicyclo[2.2.1]Heptan-2-One ((-)-26). Reductive addition of 2,3,4,6-tetra-O-acetylglucopyranosyl radical onto (+)-3 and (-)-26 were highly stereoselective giving exclusively 3-endo-(glucosylmethyl)-7-oxabicyclo[2.2.1]Heptan-2-One derivatives. The anomeric selectivity (alpha-C-glucoside vs beta-C-glucoside) was 5.5:1 with (+)-3 and 8:1 with (-)-26. The C-glucosides so-obtained were transformed into alpha-(1 --> 2)-, alpha-(1 --> 3)-, alpha-(1 --> 4)-, and alpha-(1 --> 5)-C-linked disaccharide derivatives which combine alpha-D-glucopyranose with L-altro-hexonolactone, L-manno-hexonolactone, L-mannose, and L-(talo-hexofuranosid)uronic acid, respectively.
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Substituent effects on the regioselectivity of one-carbon ring expansions of 7-oxabicyclo[2.2.1]Heptan-2-One derivatives with diazomethane
Tetrahedron Letters, 1991Co-Authors: Yves Auberson, R. Mampuya Bimwala, Pierre VogelAbstract:Reactions of CH2N2 with 5-exo,6-exo-isopropylidenedioxy-7-oxabicyclo[2.2.1]Heptan-2-One and 3-substituted derivatives have been studied. The regioselectivity of the one-carbon ring enlargement process depends on the nature of the substituent at C(3) and on its relative configuration.
N. G. Kozlov - One of the best experts on this subject based on the ideXlab platform.
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Heterocyclization of 3-aminocamphor and 3-aminoisoborneol derivatives with cyclic β-diketones and formaldehyde. Synthesis of optically active 1,2,3,4-tetrahydroquinoline derivatives with terpene substituents
Chemistry of Natural Compounds, 2012Co-Authors: A. P. Kadutskii, N. G. Kozlov, L. L. Frolova, I. N. Alekseev, A. V. KuchinAbstract:Spirocyclic 1,2,3,4-tetrahydroquinoline derivatives were prepared in quantitative yield by three-component condensation of dimedone or Meldrum’s acid with formaldehyde and (1 S ,3 R ,4 S )-1,7,7-trimethyl-3(arylamino)bicyclo[2.2.1]Heptan-2-One or (1 S ,2 S ,3 R ,4 S )-1,7,7-trimethyl-3-(arylamino)bicyclo[2.2.1]heptan2-ol.
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Sterical Hindrances as a Driving Force of Skeleton Rearrangements of Fenchone and Its Oxime in Ritter Reaction
Russian Journal of Organic Chemistry, 2003Co-Authors: S. S. Koval'skaya, N. G. KozlovAbstract:Fenchone (1,3,3-trimethylbicyclo[2.2.1]Heptan-2-One) in reaction with acetonitrile in the presence of sulfuric acid (Ritter reaction) due to steric hindrances preventing geminal addition of two nucleophile molecules gives rise to a mixture of 1,2- exo -diacetamido-6- endo ,7,7-trimethylbicyclo[2.2.1]heptane, 2- endo 6- exo -diacetamido-3,3,6-trimethylbicyclo[2.2.1]heptane, and 2- exo ,6- exo -diacetamido-1,3,3-tri- methylbicyclo[2.2.1]heptane in the ratio of ∼6:4:1. Fenchone oxime under condition of this reaction affords a mixture of stereoisomeric cis - and trans -acetamido-1-methyl-3-(α-cyanoisopropyl)cyclopentanes in 2:3 ratio.
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Synthesis and ritter reaction of 3-exo-hydroxymethyl-5,5,6-trimethylbicyclo[2.2.1]Heptan-2-One
Russian Journal of General Chemistry, 2003Co-Authors: S. S. Koval'skaya, N. G. KozlovAbstract:3-exo-Hydroxymethyl-5,5,6-trimethylbicyclo[2.2.1]Heptan-2-One was prepared by treatment of isocamphanone with Paraform in the presence of alkali in DMF. The product reacts with acetonitrile in the presence of sulfuric acid (Ritter reaction) to form a mixture of 2-(acetylamino)-3-(acetylaminomethyl)-5,5,6-trimethylbicyclo[2.2.1]hept-2-ene and 2,2-bis(acetylamino)-3-(acetylaminomethyl)-5,5,6-trimethylbicyclo[2.2.1]heptane in a ∼1:1 ratio. Attempted hydroxymethylation of isocamphanone in DMSO gave bis(isocamphanon-3-endo-yl)methane.
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5,5,6-Trimethylbicyclo[2.2.1]Heptan-2-One in the Synthesis of Carbocyclic Analogs of Prostaglandin Endoperoxides
Russian Journal of Organic Chemistry, 2001Co-Authors: F. S. Pashkovskii, S. S. Koval'skaya, F. A. Lakhvich, N. G. KozlovAbstract:1,3-Dipolar cycloaddition of nitrile oxides to 5,5,6-trimethyl- exo -2-ethynylbicyclo[2.2.1]heptan- endo -2-ol yields the corresponding 2-(isoxazol-5-yl) derivatives. Opening of the isoxazole ring in the latter gives rise to prostanoid precursors with partially built up or completed side chain. 5,5,6-Trimethyl-3-methylenebicyclo[2.2.1]Heptan-2-One reacts with nitromethane in the presence of tetramethylguanidine to afford 5,5,6-trimethyl- exo -3-(2-nitroethyl)bicyclo[2.2.1]Heptan-2-One which can be converted into the corresponding nitrile oxide by the action of phenyl isocyanate in benzene in the presence of triethylamine as catalyst. 1,3-Dipolar cycloaddition of the nitrile oxide to ethyl 4-pentynoate yields 3- exo -[5-(2-ethoxycarbonylethyl)isoxazol-3-ylmethyl]-5,5,6-trimethylbicyclo[2.2.1]Heptan-2-One. Treatment of the latter with hydroxyl amine leads to formation of the corresponding Z -oxime whose reaction with n -hexyl bromide results in transalkylation of the ester group to afford 3- exo -[5-(2-hexyloxycarbonylethyl)isoxazol-3-ylmethyl]-5,5,6-trimethylbicyclo[2.2.1]Heptan-2-One oxime.
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cis-4,4,6-trimethylbicyclo[3.1.1]Heptan-2-One in the synthesis of nitrogen-containing bicyclic compounds
Russian Journal of Electrochemistry, 2000Co-Authors: S. S. Koval’skaya, N. G. KozlovAbstract:cis -4,4,6-Trimethylbicyclo [3.1.1]Heptan-2-One (verbanone) in Mannich condensation with paraformaldehyde and dimethylamine adds an aminomethyl fragment at the most sterically accessible carbon C^3 to form an equatorial isomer. The latter treated with sulfuric acid in acetonitrile affords a mixture of two 2-azalactams, 4-(dimethylantinomethyl)-5,7,7-trimethyl-2-azabicyclo[4.1.1]octan-3-one and its deamination product 4-methylene-5,5,7-trimethyl-2-azabicyclo[4.1.1]octan-3-one in 9:1 ratio. Z-isomer of amino oxime prepared by oximation of 3-(dimethylaminomethyl)verbanone under similar conditions affords a mixture of two 3-azalactams, 4-(dimethylaminomethyl)-5,7,7-trimethyl-3-azabicyclo[4.1.1]octan-2-one and its deamination product in 5:3 ratio. Mannich bases prepared from verbanone and its oxime were converted into the respective iodomethylates. Deamination of the latter results in a single product, α,\-unsaturated ketone 3-methyleneverbanone.