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Asymmetric Allylic Alkylation (asymmetric + allylic_alkylation)
Kinds of Asymmetric Allylic Alkylation Selected AbstractsSupported Chiral Monodentate Ligands in Rhodium-Catalysed Asymmetric Hydrogenation and Palladium-Catalysed Asymmetric Allylic AlkylationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 33 2009Bert H. G. Swennenhuis Abstract A family of monodentate polystyrene-supported phosphites, phosphoramidites and phosphanes has been prepared and evaluated as ligands in rhodium-catalysed asymmetric hydrogenation and palladium-catalysed asymmetric allylic alkylation. The supported ligands yielded active and enantioselective catalysts, which in selected cases match the performance of the nonsupported counterparts. As expected, the performance of the supported ligands in the rhodium-catalysed hydrogenation depends on the nature of the ligand, the type of polymeric support, as well as on the substrate. Additionally, the supported ligands have been applied in the monodentate ligand combination approach, by combining them with nonsupported monodentate ligands. The partially supported heteroligand combinations possess different catalytic properties than the related nonsupported combinations. The heteroligand species, however, are not formed selectively, and nonsupported homoleptic complexes also contribute to the overall activity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Copper-Catalyzed Asymmetric Allylic Alkylation of Halocrotonates: Efficient Synthesis of Versatile Chiral Multifunctional Building BlocksADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2010Hartog, Tim den Abstract The highly enantioselective synthesis of ,-methyl-substituted esters is reported in up to 90% yield and up to 99% ee using copper-TaniaPhos as chiral catalyst. The transformation proved scalable to at least 6.6,mmol (1.7,g scale). The products of this transformation have been further elaborated to multifunctional building blocks with a single (branched esters and acids) or multiple stereogenic centers (vicinal dimethyl esters, as well as, hydroxy- or iodo-substituted lactones). [source] Copper-Catalyzed Asymmetric Allylic Alkylation of Racemic Cyclic Substrates: Application of Dynamic Kinetic Asymmetric Transformation (DYKAT)ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Jean-Baptiste Langlois Abstract The copper-catalyzed asymmetric allylic alkylation (AAA) is of great interest in organic synthesis. This reaction was extensively studied using a broad range of substrates, ligands and organometallic reagents. However, the use of racemic substrates was still limited. Although some processes of kinetic resolution are reported in the literature, no examples of quantitative deracemization are described as is the case for the Pd-catalyzed allylic alkylation. We present here a full account of our investigations through the development of the first example of such a process in copper-catalyzed AAA. High enantioselectivities (up to 99% ee), scope of the reaction and mechanistic considerations are reported herein. [source] Palladium-Catalyzed Asymmetric Allylic Alkylation of 2,3-Allenyl Acetates Using a Chiral Diaminophosphine OxideADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Tetsuhiro Nemoto Abstract An enantioselective synthesis of allenes through palladium-catalyzed asymmetric allylic alkylation using a chiral diaminophosphine oxide is described. The asymmetric allylic alkylations proceeded in the presence of a catalytic amount of lithium acetate at 4,°C, affording the chiral allenes in excellent yield with up to 99% ee. [source] New Recoverable Poly(ethylene glycol)-Supported C1 - Diamino-oligothiophene Ligands for Palladium-Promoted Asymmetric Allylic Alkylation (AAA) ReactionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 12-13 2006Marco Bandini Abstract A new class of chiral C1 -symmetrical diamino-oligothiophene ligands easy-grafted on a soluble polymeric support (MeOPEG5000) is described. The diamines were found to be effective promoting agents for the [Pd(0)]-catalysed asymmetric allylic alkylation (AAA) of dimethyl malonate in high yields and excellent enantioselectivity (ee up to 99,%). The supported chiral ligand was readily recovered by precipitation and filtration was recycled up to three times without an appreciable loss in activity. The recycle of the organometallic catalytic system was also investigated. [source] Berichtigung: Copper-Free Asymmetric Allylic Alkylation with Grignard ReagentsANGEWANDTE CHEMIE, Issue 30 2010Olivier Jackowski Dr. No abstract is available for this article. [source] Copper-Free Asymmetric Allylic Alkylation with Grignard Reagents,ANGEWANDTE CHEMIE, Issue 19 2010Olivier Jackowski Dr. AAA,lternative: Die Titelreaktion mit Allylbromiden verläuft unter Katalyse durch N-heterocyclische Carbene. Die Reaktion ergibt gute Enantioselektivitäten und mitunter eine hervorragende ,-Regioselektivität, insbesondere beim Aufbau quartärer Stereozentren. [source] Construction of Two Vicinal Quaternary Carbons by Asymmetric Allylic Alkylation: Total Synthesis of Hyperolactone,C and (,)-Biyouyanagin,A,ANGEWANDTE CHEMIE, Issue 49 2009Chao Du No abstract is available for this article. [source] Construction of Two Vicinal Quaternary Carbons by Asymmetric Allylic Alkylation: Total Synthesis of Hyperolactone,C and (,)-Biyouyanagin,A,ANGEWANDTE CHEMIE, Issue 42 2009Chao Du Aller Anfang ist AAA: Ausgehend von einer palladiumkatalysierten asymmetrischen allylischen Alkylierung (Pd-AAA; siehe Schema) benötigten die kurzen und effizienten Synthesen von Hyperolacton,C und (,)-Biyouyanagin,A nur sechs bzw. sieben Schritte bei 20,% bzw. 8,% Gesamtausbeute. Die Enantiomere dieser Naturstoffe waren mit der gleichen Sequenz ebenfalls zugänglich. [source] ChemInform Abstract: Copper-Catalyzed Asymmetric Allylic Alkylation of Halocrotonates: Efficient Synthesis of Versatile Chiral Multifunctional Building Blocks.CHEMINFORM, Issue 35 2010Tim den Hartog Abstract The highly enantioselective synthesis of ,-methyl-substituted ester (III) is reported. [source] ChemInform Abstract: Direct Asymmetric Allylic Alkylation of Butenolides with Morita,Baylis,Hillman Carbonates.CHEMINFORM, Issue 27 2010Hai-Lei Cui 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: Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of Enol Carbonates.CHEMINFORM, Issue 19 2010Barry M. Trost 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: Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of Enol Carbonates.CHEMINFORM, Issue 19 2010Barry M. Trost 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: Catalytic Double Stereoinduction in Asymmetric Allylic Alkylation of Oxindoles.CHEMINFORM, Issue 19 2010Barry M. Trost 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: Construction of Two Vicinal Quaternary Carbons by Asymmetric Allylic Alkylation: Total Synthesis of Hyperolactone C and (-)-Biyouyanagin A.CHEMINFORM, Issue 6 2010Chao Du 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: Synthesis of Novel Chiral Phosphine-Triazine Ligand Derived from ,-Phenylethylamine for Pd-Catalyzed Asymmetric Allylic Alkylation.CHEMINFORM, Issue 30 2008Jia Di Huang 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, Reaction, and Recycle of Fluorous Palladium Catalysts for an Asymmetric Allylic Alkylation Without Using Fluorous Solvents.CHEMINFORM, Issue 6 2006Takashi Mino Abstract For Abstract see ChemInform Abstract in Full Text. [source] Total Synthesis of Ustiloxin D and Considerations on the Origin of Selectivity of the Asymmetric Allylic Alkylation.CHEMINFORM, Issue 21 2005Andrew M. Sawayama No abstract is available for this article. [source] Development of Chiral (S)-Prolinol-Derived Ligands for Palladium-Catalyzed Asymmetric Allylic Alkylation: Effect of a Siloxymethyl Group on the Pyrrolidine Backbone.CHEMINFORM, Issue 6 2005Youichi Tanaka Abstract For Abstract see ChemInform Abstract in Full Text. [source] Asymmetric Allylic Alkylation of Ketone Enolates: An Asymmetric Claisen Surrogate.CHEMINFORM, Issue 6 2005Erin C. Burger Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis of Chiral Chromans by the Pd-Catalyzed Asymmetric Allylic Alkylation (AAA): Scope, Mechanism, and Applications.CHEMINFORM, Issue 5 2005Barry M. Trost Abstract For Abstract see ChemInform Abstract in Full Text. [source] New Dihydroxy Bis(oxazoline) Ligands for the Palladium-Catalyzed Asymmetric Allylic Alkylation: Experimental Investigations of the Origin of the Reversal of the Enantioselectivity.CHEMINFORM, Issue 25 2004Hassan Ait-Haddou Abstract For Abstract see ChemInform Abstract in Full Text. [source] Chiral Pyridinyloxazolidine Ligands for the Pd-Catalyzed Asymmetric Allylic Alkylation.CHEMINFORM, Issue 7 2004Jin-Koo Yoon No abstract is available for this article. [source] Synthesis of Novel Planar Chiral Ferrocene and Cyclopentadienyl Manganese Tricarbonyl Derivatives and Their Use as Chiral Ligands in the Palladium-Catalyzed Asymmetric Allylic Alkylation.CHEMINFORM, Issue 44 2003Jae Hoon Lee Abstract For Abstract see ChemInform Abstract in Full Text. [source] New Enantioselective Chiral Imidazolidine Ligands for Pd-Catalyzed Asymmetric Allylic Alkylation.CHEMINFORM, Issue 21 2003En-Kyung Lee Abstract For Abstract see ChemInform Abstract in Full Text. [source] A New Methodology for Synthesis of a Chiral Phosphinocarboxylic Acid Through Michael Cyclization,Aldol Tandem Reaction of Chiral ,,,,,,,-Unsaturated Bisphosphine Oxide and Application in Palladium-Catalyzed Asymmetric Allylic Alkylation.CHEMINFORM, Issue 3 2003Hediki Inoue No abstract is available for this article. [source] ChemInform Abstract: Palladium-Catalyzed Asymmetric Allylic Alkylation Using (R)-2-(Methoxymethyl)pyrrolidine-Derived Aminophosphine Ligands.CHEMINFORM, Issue 12 2002Takashi Mino 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: Novel Chiral Phosphine,Oxazinane Ligands in Palladium-Catalyzed Asymmetric Allylic Alkylation.CHEMINFORM, Issue 41 2001Takashi Mino 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: Diphosphites as a Promising New Class of Ligands in Pd-Catalyzed Asymmetric Allylic Alkylation.CHEMINFORM, Issue 40 2001Montserrat Dieguez 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] New Dihydroxy Bis(Oxazoline) Ligands for the Palladium-Catalyzed Asymmetric Allylic Alkylation: Experimental Investigations of the Origin of the Reversal of the EnantioselectivityCHEMISTRY - A EUROPEAN JOURNAL, Issue 3 2004Hassan Aït-Haddou Dr. Abstract The origin of the reversal of the enantioselectivity in the palladium-catalyzed allylic alkylation of rac -1,3-diphenyl-2-propenyl acetate with dimethyl malonate anion using chiral dihydroxy bis(oxazoline) "BO" ligands derived from (1S,2S)-(+)-2-amino-1-phenyl-1,3-propanediol was investigated. To determine the structural effects of the dihydroxy BO ligand on this unique phenomenon, new homochiral dihydroxy BO ligands were prepared from L -threonine and L -serine and were assessed in the transformation. The results obtained with these novel BO ligands, compared with the one obtained by using the dihydroxy BO ligands derived from (1S,2S)-(+)-2-amino-1-phenyl-1,3-propanediol, reveal that the reversal in the enantioselectivity observed with the dihydroxy BO ligand depends on the structure of the ligand. The effect of different bases used to generate the dimethyl malonate anion was also examined. The results are discussed in terms of the interaction of one hydroxy group in the intermediate ,-allyl palladium complex with the dimethyl malonate anion. [source] | ||||||||||||||||||||||