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Cascade Reactions (cascade + reaction)
Kinds of Cascade Reactions Selected AbstractsOrganocatalytic Asymmetric Friedel,Crafts Alkylation/Cascade Reactions of Naphthols and Nitroolefins.CHEMINFORM, Issue 41 2007Tian-Yu Liu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis of 3,-Deoxyribolactones using a Hydrolysis-Induced Lactonization Cascade Reaction of Epoxy CyanohydrinsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2008Danielle J. Vugts Abstract The synthesis of 3,-deoxyribolactones was accomplished in a few steps from the commercially available 3-decyn-1-ol in 44,% overall yield. The key transformation comprises a one-pot four-reaction hydrolysis-induced lactonization cascade. The strategy was employed to efficiently access optically active 5,-chloro-3,-deoxyribolactones. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Catalytic Asymmetric Intramolecular Cascade Reaction for the Construction of Functionalized Benzobicyclo[4.3.0] Skeletons.ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2010Remote Control of Enantioselectivity Abstract A catalytic asymmetric version of the intramolecular ylide annulation has been developed which affords high ee values and diastereoselectivities and which further shows that spirobiindane-based chiral phosphines can be excellent organocatalysts. Both optically active benzobicyclo[4.3.0] compounds 2 and 2, with three continuous stereogenic centers could be obtained as major products selectively under neutral and mild conditions just by a choice of an additive. [source] Highly Functional Poly(meth)acrylates via Cascade ReactionMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 2 2009Dragos Popescu Abstract A new route to the synthesis of highly functional and reactive polymethacrylates via cascade reactions comprising enzymatically and chemically catalyzed steps is presented. Transacylation of methyl acrylate and methyl methacrylate as substrates with different functional alcohols in the presence of Novozyme 435 leads to a mixture of functional monomers, which in a subsequent step was copolymerized via free radical polymerization, resulting in polymethacrylates with predefined functionalities. Hydrophilic, hydrophobic, as well as ionic methacrylate repeating units were assembled in a copolymer and adjusted for surface coatings. [source] Enantioselective Synthesis of Trifluoromethyl-Substituted 2-Isoxazolines: Asymmetric Hydroxylamine/Enone Cascade Reaction,ANGEWANDTE CHEMIE, Issue 33 2010Kazutaka Matoba Eine Sequenz von Addition, Cyclisierung und Dehydrierung liefert die biologisch wichtigen chiralen 3,5-Diaryl-5-(trifluormethyl)-2-isoxazoline 1 in hervorragenden Ausbeuten und hohen Enantioselektivitäten. Der gezielte Zugang zum S - oder R -Enantiomer der Produkte wurde durch die Wahl eines geeigneten Phasentransferkatalysators (2) eröffnet. [source] Rhodium-Catalyzed Cascade Reaction: Aryl Addition/Intramolecular Esterification to Access 3-Aryl and 3-Alkenyl Phthalides,ANGEWANDTE CHEMIE, Issue 21 2010Zhishi Ye Eins nach dem anderen: Die Titelreaktion (siehe Schema; cod=1,5-Cyclooctadien, dppb=1,4-Bis(diphenylphosphanyl)butan) eröffnet einen praktikablen Zugang zu 3-Aryl- und 3-Alkenylphthaliden in mäßigen bis guten Ausbeuten, wobei einige funktionelle Gruppen toleriert werden. [source] A Triple-Aldol Cascade Reaction for the Rapid Assembly of Polyketides,ANGEWANDTE CHEMIE, Issue 15 2010Brian Äußerst wenig Katalysator wird für die Titelreaktion benötigt, bei der 1 mit einfachen Aldehyden zu 3,5,7-Trisilyloxyaldehyden reagiert (siehe Schema). Iodbenzol erleichtert die dritte Aldolreaktion, offenbar indem es als Lewis-Base gegenüber dem Silylkatalysator wirkt. Tf=Trifluormethansulfonyl. [source] ChemInform Abstract: A New Pd-Catalyzed Cascade Reaction for the Synthesis of Strained Aromatic Polycycles.CHEMINFORM, Issue 36 2008Gaelle Blond Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Acylzirconocene Chloride: Formation of Carbocycles by Palladium-Catalyzed Cascade Reaction.CHEMINFORM, Issue 7 2008Yuji Hanzawa Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: An Efficient Synthesis of New Class of Pyrazolo[3,4-b]pyridine-6-one Derivatives by a Novel Cascade Reaction.CHEMINFORM, Issue 4 2008Feng Shi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Synthesis of ,-Amino Carbonyl Compounds via a Zn(OTf)2 -Catalyzed Cascade Reaction of Anilines with Aromatic Aldehydes and Carbonyl Compounds.CHEMINFORM, Issue 5 2007Yun-Yun Yang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Expeditious Syntheses of Conjugated Allenyl Esters and Oxazoles Through a Cascade Reaction of ,-Alkynyl Malonates under Alkaline Conditions.CHEMINFORM, Issue 28 2006Shigeki Sano Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Tris(trimethylsilyl)silyl-Governed Aldehyde Cross-Aldol Cascade Reaction.CHEMINFORM, Issue 19 2006Matthew B. Boxer Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Tetrahydropyran Rings from a Mukaiyama,Michael Cascade Reaction.CHEMINFORM, Issue 12 2006Megan L. Bolla Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Radical Cascade Reaction with 1,4-Dienes and 1,4-Enynes Using 2-(Iodomethyl)cyclopropane-1,1-dicarboxylate as a Homoallyl Radical Precursor: One-Step Synthesis of Bicyclo[3.3.0]octane Derivatives.CHEMINFORM, Issue 35 2002Osamu Kitagawa Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Synthesis and X-Ray Characterization of a New Polycondensed Heterocycle (II) Obtained by a Novel Mn(III)-Mediated Cascade Reaction of 2-Cyanophenyl Isothiocyanate.CHEMINFORM, Issue 50 2001Gianluca Calestani Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Nd(OTf)3 -Catalyzed Cascade Reactions of Vinylidenecyclopropanes with Enynol: A New Method for the Construction of the 5,7,6 Tricyclic Framework and Its Scope and LimitationsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2009Liang-Feng Yao Abstract We report in this paper a Lewis acid [Nd(OTf)3]-catalyzed protocol to construct compounds containing a 5,7,6 tricyclic framework in good yield from readily accessible starting materials vinylidenecyclopropanes (VDCPs) 1 and enynols 2a,c under mild conditions. Upon examination of the scope and limitations of this reaction, it was found that the corresponding highly functionalized cyclopentane derivatives could be formed in good yields from the reaction VDCPs 1 and enol 2e or dienol 2c under identical conditions.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] A Materials Approach to the Dual-Site Isolation of Catalysts Bonded to Linear Polymers and Small, Ionic Molecules for Use in One-Pot Cascade Reactions,ADVANCED MATERIALS, Issue 21 2008A. Lee Miller II Site isolation of ionic catalysts and polymer-bound catalysts is achieved by placement on different sides of PDMS membranes. Ionic molecules and polymers do not flux through the PDMS membranes, but organic molecules can flux through the membranes and react with catalysts that are incompatible with each other. This is a general approach to site-isolate catalysts from each other. [source] Copper(I)-Catalyzed Synthesis of Novel 4-(Trifluoromethyl)-[1,2,3]triazolo[1,5- a]quinoxalines via Cascade Reactions of N -(o -Haloaryl)alkynylimine with Sodium AzideADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 8 2010Zixian Chen Abstract Novel tricyclic 4-(trifluoromethyl)-[1,2,3]triazolo[1,5- a]quinoxalines were readily prepared from N -(o -haloaryl)alkynylimines and sodium azide via copper(I)-catalyzed tandem reactions. This synthetic strategy provides an efficient way to access a library of novel heterocyclic compounds that are of interest in drug discovery. [source] Cascade Reactions: Catalytic Synthesis of Functionalized 1,3-Dihydroisobenzofuran and Tetrahydrofuran Derivatives by Sequential Nucleophilic Ring Opening,Heterocyclization, Oxidative Carbonylation of AlkynyloxiranesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Nicola Della Ca' Abstract Differently substituted alkynyloxiranes were efficiently converted into functionalized 1,3-dihydroisobenzofurans and tetrahydrofuran derivatives in fair to good yields by a new cascade reaction, consisting of a sequential nucleophilic ring opening,heterocyclization,oxidative carbonylation process. Reactions were carried out at 80,100,°C and under a 3:1 mixture of carbon monoxide and air (total pressure=32,42,atm at 25,°C) in methanol or acetonitrile/methanol mixtures in the presence of catalytic amounts of palladium diiodide in conjunction with an excess of potassium iodide. The nucleophilic species beginning the cascade process by regioselective attack to the less hindered carbon of the oxirane ring can be methanol itself or iodide anions. [source] Tuning Selectivity in Terpene Chemistry: Selective Hydrogenation versus Cascade Reactions over Copper CatalystsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2005F. Zaccheria Abstract The selectivity of Cu/Al2O3 under very mild catalytic hydrogenation conditions can be tuned only by switching the solvent. Geraniol can be converted in a one-pot one-step process into a mixture of citronellol and menthol in hydrocarbon solvents or reduced to citronellol with 98% selectivity in 2-propanol without any additive. Both reactions can be applied to essential oils or synthetic mixtures containing geraniol, citronellal and nerol. [source] Cascade Reactions in Polymeric Nanoreactors: Mono (Rh)- and Bimetallic (Rh/Ir) Micellar Catalysis in the Hydroaminomethylation of 1-OcteneMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 11 2008Barbara Gall Abstract The concept of micellar catalysis was transferred to the hydroaminomethylation of 1-octene with N,N -dimethylamine. In the first series of experiments a rhodium(I) complex with amphiphilic triphenylphosphane functionalized poly(2-oxazoline)s as macroligand was applied as catalyst. Results obtained under standard hydroformylation conditions (T,=,100,°C, p,=,50 bar) were not satisfying with regard to activities and selectivities of the hydroaminomethylation reaction. Rising the temperature to 150,°C increased the yield of amine to 22% with a corresponding n/iso selectivity of 7.5 and a TOF number of 461 h,1. Best results were obtained by applying a dual Rh/Ir catalyst within the polymeric micelles leading at lower temperature of 130,°C to an amine yield of 24% with a corresponding n/iso selectivity of 11 and TOF numbers of about 600 h,1. [source] Polarity-Directed One-Pot Asymmetric Cascade Reactions Mediated by Two Catalysts in an Aqueous Buffer,ANGEWANDTE CHEMIE, Issue 13 2010Steven Die Polarität ist es, die den Unterschied zwischen Substraten mit sonst fast identischer chemischer Reaktivität macht. Eine Eintopf-Kaskadenreaktion von Nitromethan und zwei aliphatischen Aldehyden ähnlicher Reaktivitäten wurde entwickelt (siehe Schema). Die Verwendung eines zweiphasigen Reaktionsmediums mit zwei verschiedenen organischen Katalysatoren führte zur hochselektiven Bildung eines einzigen von vier möglichen Produkten. [source] Asymmetric Organocatalytic Cascade Reactions with ,-Substituted ,,,-Unsaturated Aldehydes,ANGEWANDTE CHEMIE, Issue 42 2009Patrizia Galzerano ,-Verzweigung erforderlich: Die erste hoch enantioselektive Aktivierung von ,-substituierten ,,,-ungesättigten Aldehyden mit einem Aminkatalysator wird vorgestellt. Das chirale primäre Amin 1 aktiviert selektiv ,-verzweigte Enale für eine Iminiumion/Enamin-Sequenz in Reaktionskaskaden aus Friedel-Crafts- oder Sulfa-Michael-Reaktion und Aminierung. Die hoch funktionalisierten Produkte mit zwei benachbarten Stereozentren werden mit hohen Enantiomerenüberschüssen isoliert. [source] ChemInform Abstract: Facile Synthesis of Benzothiazoles via Cascade Reactions of 2-Iodoanilines, Acid Chlorides and Lawesson,s Reagent.CHEMINFORM, Issue 14 2010Qiuping Ding Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Cascade Reactions: Catalytic Synthesis of Functionalized 1,3-Dihydroisobenzofuran and Tetrahydrofuran Derivatives by Sequential Nucleophilic Ring-Opening,Heterocyclization,Oxidative Carbonylation of Alkynyloxiranes.CHEMINFORM, Issue 9 2010Nicola Della Ca' Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Nd(OTf)3 -Catalyzed Cascade Reactions of Vinylidenecyclopropanes with Enynol: A New Method for the Construction of the 5,7,6 Tricyclic Framework and Its Scope and Limitations.CHEMINFORM, Issue 52 2009Liang-Feng Yao Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: New Gas-Phase Cascade Reactions of Stabilized Phosphorus Ylides Leading to Ring-Fused Indoles and to Quinolines.CHEMINFORM, Issue 16 2009R. Alan Aitken Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Lewis Acid Catalyzed Cascade Reactions of Diarylvinylidenecyclopropanes and 1,1,3-Triarylprop-2-yn-1-ols or Their Methyl Ethers.CHEMINFORM, Issue 7 2009Min Shi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Highly Efficient and Mild Cascade Reactions Triggered by Bis(triphenyl)oxodiphosphonium Trifluoromethanesulfonate and a Concise Total Synthesis of Camptothecin.CHEMINFORM, Issue 38 2007Hai-Bin Zhou Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] | |||||||||||||||||||||||||