Showing papers on "Enone published in 1984"
376 citations
TL;DR: The phenyldimethylsilyl group can be converted in two steps, protodesilylation and peracid-mediated rearrangement, into a hydroxy group with retention of configuration as discussed by the authors.
Abstract: The phenyldimethylsilyl group can be converted in two steps, protodesilylation and peracid-mediated rearrangement, into a hydroxy group with retention of configuration: β-phenyldimethylsilyl carbonyl compounds are thus revealed to be masked aldol products.
280 citations
01 Jan 1984
TL;DR: In this article, the authors present a survey of the application of electron transfer in organic chemistry, including photooxygenation, N-Arylanilides and N-Benzoylenamines.
Abstract: 1. Photoaddition and Photocyclization Processes of Aromatic Compounds.- 1. Introduction.- 2. Intermolecular Reactions.- 2.1. Arenes and Ethenes.- 2.2. Arenes and Acetylenes.- 2.3. Arenes and 1,3-Dienes.- 2.4. Acyclic Additions to Arenes and Reduction Processes.- 2.5. Arene Photodimerizations.- 3. Intramolecular Cyclization Processes.- 3.1. Arene-Ethene and Arene-Ethyne Systems.- 3.1.1. Hydrocarbon Systems.- 3.1.2. Aryl Enones.- 3.1.3. Aryl Ethenyl Ethers, Thioethers, and N- Aryl Enamines.- 3.1.4. Cyclizations of N-Arylanilides and N-Benzoylenamines.- 3.2. Aryl Butadiene and Butenyne Systems.- 3.3. Intramolecular Photocoupling of Arenes.- 3.3.1. Stilbene-Phenanthrene-Type Cyclizations.- 3.3.2. Photocoupling of Arenes with Intervening Units Other Than Ethylene.- 3.3.3. Coupling of Arenes as a Result of Halogen Acid Photoelimination.- 3.4. Photocyclizations of o-Substituted Arenes.- References.- 2. Enone Photochemical Cycloaddition in Organic Synthesis.- 1. Introduction.- 2. The Reaction Mechanism.- 3. Regiochemistry of Enone Cycloaddition.- 4. Stereochemistry of Enone Cycloaddition.- 5. Intramolecular Enone Cycloadditions.- 6. The de Mayo Reaction.- 6.1. Cyclic Diketones.- 6.2. Acyclic 1,3-Diketones.- 6.3. Intramolecular Additions of Enolized Diketones.- 7. Intermolecular Enone Cycloaddition.- 8. Photochemical Cycloaddition between Enones and Allenes.- References.- 3. Synthetic Aspects of Photochemical Electron Transfer Reactions.- 1. Introduction.- 1.1. Synthetic Applications of Photochemical Reactions.- 1.2. Electron Transfer in Excited-State Chemistry.- 1.2.1. Exciplex Formation and Decay.- 1.2.2. Electron Transfer Efficiencies and Rates.- 1.3. Chemical Consequence of Electron Transfer.- 1.3.1. General Survey and Predictions.- 1.3.2. Overview of Coverage.- 2. Reaction Pathways Followed in Electron Transfer Photochemistry.- 2.1. Alkenes and Strained Ring Hydrocarbons.- 2.1.1. Alkenes as Electron Acceptors and Donors.- 2.1.2. Cyclopropene Electron Transfer Photochemistry.- 2.1.3. Cyclopropanes and Other Strained Ring Systems as Electron Donors.- 2.2. Amines.- 2.2.1. General Considerations.- 2.2.2. Amine-Olefin Electron Transfer Photochemistry.- 2.2.3. Amine-Ketone Electron Transfer Photochemistry.- 2.3. Ketones.- 2.3.1. General Considerations.- 2.3.2. Ketone Electron Transfer Photochemistry.- 2.3.3. Quinone Electron Transfer Photochemistry.- 2.4. Electron Transfer Photooxygenations.- 2.4.1. General Considerations.- 2.4.2. Class 1 Photooxygenations.- 2.4.3. Class 2 Photooxygenations.- 2.4.4. Class 3 Photooxygenations.- 2.5. Aromatic Systems.- 2.5.1. Aromatic Photosubstitution Reactions.- 2.5.2. Photobenzylations by Electron Transfer Mechanisms.- 2.5.3. Birch and Related Photoreductions of Aromatic Compounds.- 2.6. Electron Transfer Photochemistry of Nitrogen Heteroaromatic Salts and Related Systems.- 2.6.1. General Considerations.- 2.6.2. Electron Transfer Photochemistry of Pyridinium and Related Salts.- 2.6.3. Iminium Salt Photochemistry.- 2.7. Other Electron Transfer Initiated Photoreactions.- 2.7.1. Olefin Cycloadditions and Retro Processes.- 2.7.2. Phthalimide Photochemistry.- 2.7.3. Photodecarboxylations.- 2.7.4. Metal Catalyzed Photoreactions.- References.- 4. Phthalimide and Its Derivatives.- 1. Introduction.- 2. Hydrogen Abstraction.- 2.1. Photoreduction and Photoaddition.- 2.2. Intramolecular Photocyclization.- 3. Reaction with Alkenes.- 3.1. Ring Expansion.- 3.2. Solvent Incorporation.- 3.3. Intramolecular Reaction.- 4. Cleavage Reactions.- 4.1. ?-Cleavage.- 4.2. ?-Cleavage.- 5. Spectra and Excited States.- 6. Summary.- References.- 5. Photochemical Addition Reactions in the Benzo(b)Thiophene, Benzo(b)Furan, and Indole Series.- 1. Introduction.- 1.1. Absorption and Emission Characteristics.- 2. Photochemistry.- 2.1. Oxetan Formation.- 2.2. Dimerization.- 2.3. Photochemical Reactions with Acetylene Esters.- 3. Benzo(b)thiophene.- 4. Indoles.- 5. Benzo(b)thiophenes.- 6. Benzo(b)furans.- 7. Thermal Reactions of the 2-Hetero-bicyclo(3.2.0)heptadienes.- 8. 1,3-Dimethylindole.- 9. Photocycloadditions of Benzo(b)thiophene to Alkenes.- References.- 6. Azirine Photolysis and Cycloaddition Reactions.- 1. Introduction.- 1.1. UV Spectra of Arylazirines.- 1.1.1. Evidence for Nitrile Ylide Formation.- 2. Cycloaddition Reactions.- 2.1. Addition with Electron-Deficient Olefins.- 2.1.1. Mechanism of Cycloaddition to Olefines.- 2.2. Addition to Aldehydes and Ketones.- 2.3. Addition to Esters.- 2.4. Additions to Acid Chloride and Anhydrides.- 2.5. Additions to Carbon Dioxide and Carbon Disulfide.- 2.6. Additions to Ketenes, Carbodiimides, Isocyanates, and Isothiocyanates.- 3. Photodimerization of Azirines.- 4. Intramolecular Cycloaddition Reactions.- 4.1. Rearrangement of 2-Vinylazirines.- 4.2. Rearrangements of Isoxazoles and Oxazoles.- 5. Mechanisms for Cycloaddition Reactions of Nitrile Ylides.- 5.1. The 1,1-Cycloaddition Process.- 5.2. Summary of 1,1-Cycloaddition Mode.- 5.3. Other Examples of 1,1-Cycloaddition.- 5.4. 1,1- and 1,3-Cycloaddition in Competition.- 6. Fragmentation Reactions.- 6.1. Competitive Involvement of Ylide Formation.- 7. Group Migration Reactions.- References.- 7. Photoremovable Protecting Groups.- 1. Introduction.- 2. Alcohols.- 2.1. Sulfonic Acid Esters.- 2.2. o-Nitrobenzyl Ethers.- 2.3. Nitrates, Nitrites, Dimelhylthiocarbamates, and Aryl Azides.- 3. Diols.- 4. Phenols.- 5. Aldehydes and Ketones.- 6. Carboxylic Acids and Amides.- 6.1. o-Nitrobenzyl Esters.- 6.2. o-Nitrophenylamino Derivatives.- 6.3. Phenacyl Esters.- 6.4. 2,4-Dinitrophenylthio Esters, Benzoin Esters, and Aryl Azides.- 7. Amines.- 7.1. Benzyloxycarbonyl Compounds.- 7.2. Sulfonamides.- 7.3. Formamides, N-Oxides, and 4,5-Diaryl-4-oxazoline-2-ones.- 8. Phosphates.- 9. Conclusion.- References.- 8. Photochemical Synthesis of Oxetans.- 1. Introduction.- 2. Reaction Mechanism.- 2.1. Carbonyl Excited States.- 2.2. Triplet Energies.- 2.3. Competing Reactions.- 2.4. Hydrogen Abstraction.- 3. Alkene Addends.- 3.1. Simply Substituted Alkenes.- 3.2. Dienes and Trienes.- 3.3. Allenes and Ketenimines.- 3.4. Electron-Deficient Alkenes.- 3.5. Vinyl Ethers.- 3.6. Heteroaromatics.- 4. Carbonyl Addends.- 4.1. ?-Dicarbonyls.- 4.2. Quinones.- 4.3. Miscellaneous Carbonyls.- 4.4. Enones and Ynones.- 5. Intramolecular Cycloadditions.- 6. Chemical Reactions of Oxetans.- References.- 9. Equipment and Techniques.- 1. Mercury Vapor Lamps.- 2. Lamps in Conjunction with Filters.- 3. Photochemical Apparatus.- 4. Actinometry.- 4.1. Solution Phase Systems.- 4.2. Electronic Actinometers.- 5. Purity of Solvents and Gases.- References.
213 citations
TL;DR: The high endo/exo product ratio in the Diels-Alder reaction of cyclopentadiene with methyl vinyl ketone in water does not reflect aggregation, but the ratio is affected by salts which change the hydrophobicity of the medium.
206 citations
TL;DR: La cyclisation des acetates d'ethynyl-1 propene-2ols 1, catalysee par PdCl 2 (MeCN) 2 conduit aux acetates de cyclo pentadiene-1,4ols qui se transforment en cyclopentene- 2ones
Abstract: La cyclisation des acetates d'ethynyl-1 propene-2ols-1, catalysee par PdCl 2 (MeCN) 2 conduit aux acetates de cyclo pentadiene-1,4ols qui se transforment en cyclopentene-2ones
189 citations
TL;DR: Par chauffage de derives de cyclobutenone, formation de vinyl-cetenes; ces derniers se combinent avec des alcyne-1yl-ethers, -sulfures et -amines selon un processus de cycloaddition [2+2] regioselective as mentioned in this paper.
Abstract: Par chauffage de derives de cyclobutenone, formation de vinyl-cetenes; ces derniers se combinent avec des alcyne-1yl-ethers, -sulfures et -amines selon un processus de cycloaddition [2+2] regioselective. Preparation de methylthio-3-, methoxy-3 et methylamino-3 phenols
152 citations
143 citations
130 citations
TL;DR: In this article, new poly-α-aminoacids modified at the C or N -terminal groups were synthetised and employed in the asymmetric epoxidation of chalcone.
129 citations
85 citations
TL;DR: Dimethyl diazomalonate smoothly deoxygenates epoxides to alkenes with rhodium(II) acetate catalysis as mentioned in this paper, but it is not suitable for the use of polyethylene.
TL;DR: In this paper, the cyclisation of methoxy-7 cycloheptadiene-2,4 propanal intermediaire has been studied in the context of drug design.
Abstract: Synthese des composes du titre a partir de la cycloheptatrienone L'etape cle est la cyclisation du methoxy-7 cycloheptadiene-2,4 propanal intermediaire
TL;DR: The oxidation of α,β-unsaturated ketones with manganese (III) triacetate in benzene furnishes α'-acetoxyenones in good yields as mentioned in this paper.
TL;DR: Preparation of phenyl-1 alcene-1ones-3 et diphenyl- 1,5 pentadiene -1,4 one-3 and dibenzylidene cyclanones as mentioned in this paper.
Abstract: Preparation de phenyl-1 alcene-1ones-3 et de diphenyl-1,5 pentadiene-1,4 one-3 et dibenzylidene cyclanones
TL;DR: Prostaglandine spielen im menschlichen Korper eine erstaunliche Rolle; bisher sind mehr als 5000 Prostaglandsin-Analoga hergestellt und auf ihre biologischen Wirkungen untersucht worden as mentioned in this paper.
Abstract: Prostaglandine spielen im menschlichen Korper eine erstaunliche Rolle. Nach der vollstandigen Strukturaufklarung Anfang der sechziger Jahre wurden enorme Anstrengungen unternommen, eine leistungsfahige chemische Synthese zu entwickeln, denn diese in der Natur sehr sparlich vorkommenden, lokal wirkenden Hormone konnen nur durch Totalsynthese in ausreichender Menge bereitgestellt werden. Unter den vielen Synthesen, von denen die meisten linear oder sequentiell ablaufen, ist Coreys Synthese wohl die vielseitigste; bisher sind mehr als 5000 Prostaglandin-Analoga hergestellt und auf ihre biologischen Wirkungen untersucht worden. Einige naturliche Prostaglandine und deren Analoga werden bereits klinisch verwendet. Angesichts der fortwahrenden Expansion auf diesem Gebiet faszinierte uns die Idee, auf der Grundlage einer neuen Strategie einen hochkonvergenten Zugang zu Prostaglandinen zu schaffen. Die Entdeckung einer hochenantioselektiven Methode zur Reduktion prochiraler Ketone und die Entwicklung eines Verfahrens zur doppelten vicinalen CC-Verknupfung mit Enonen haben eine Eintopfsynthese zum Aufbau des vollstandigen Prostaglandin-Skeletts ermoglicht. Dabei wird eine chirale 4-oxygenierte 2-Cyclopentenon-Einheit mit zwei Bausteinen fur die Seitenketten verbunden. Dieses Verfahren ist effizient und flexibel, und es ermoglicht die Herstellung aller naturlich vorkommenden Prostaglandine und einer breiten Palette von Analoga.
TL;DR: Conversion in presence of SbF 5 des ([hydryl-2 perfluoroalkyl] methyl) ethers and de [methyl perfluoralcene-1 yl] ethers en fluorures d'acyle, cetones, Cetoesters, enones et cetenes fluores.
Abstract: Conversion en presence de SbF 5 des ([hydryl-2 perfluoroalkyl] methyl) ethers et de [methyl perfluoroalcene-1 yl] ethers en fluorures d'acyle, cetones, cetoesters, enones et cetenes fluores
TL;DR: Synthese du compose du titre a partir du trimethyleneacetal du decahydro dimethyl-13,15 dioxo-2,10 ethyl-16 oxacyclohexadecinnecarbothialdehyde-6.
Abstract: Synthese du compose du titre a partir du trimethyleneacetal du decahydro dimethyl-13,15 dioxo-2,10 ethyl-16 oxacyclohexadecinnecarbothialdehyde-6. Stereoselectivite, controle cinetique
Journal Article•
TL;DR: Synthese de tri-, tetra-and pentamethylene-4,5 amino-2 aryl-4 pyrimidines a partir de guanidine and d'arylidene-2 cyclanones; synthese des composes du titre as mentioned in this paper.
Abstract: Synthese de tri-, tetra- et pentamethylene-4,5 amino-2 aryl-4 pyrimidines a partir de guanidine et d'arylidene-2 cyclanones; synthese des composes du titre a partir de guanidine et de diarylidene-2,6 cyclohexanones
TL;DR: Borohydride exchange resin (BER) exhibited selectivity in the reduction of α, β-unsaturated carbonyl compounds to the corresponding unsaturated alcohols as mentioned in this paper.
TL;DR: In this article, t-butyl hydroperoxide was used to give α,β-unsaturated ketones, selectively in the presence of certain alcohols, and in moderate to excellent yields.
TL;DR: In this paper, the formylation and acylation of bromures d'alkylmagnesium and Dalkyl-lithium par reaction avec les dimethylamides des acides formique, acetique, and benzoique is described.
Abstract: Etude de la formylation et acylation de bromures d'alkyl-magnesium et d'alkyl-lithium par reaction avec les dimethylamides des acides formique, acetique et benzoique
TL;DR: On prepare la clavulone I et son isomere 5,6-(E), analogues des prostaglandines, a partir du cyclopentadienure de lithium et du iodo-1 octyne-2 as discussed by the authors.
Abstract: On prepare la clavulone I et son isomere 5,6-(E), analogues des prostaglandines, a partir du cyclopentadienure de lithium et du iodo-1 octyne-2
TL;DR: Asymmetric synthetic methodology was introduced for preparation of 3,3-disubstituted cyclopentanones, including (+)-α-cuparenone, of high enantiomeric purity as mentioned in this paper.
TL;DR: Several trans-difluoro olefins have been prepared from chlorotrifluorethylene via diffluorovinylsilicon intermediates as mentioned in this paper.