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Facile Access (facile + access)
Selected AbstractsFacile Access to Optically Active Ferrocenyl Derivatives with Direct Substitution of the Hydroxy Group Catalyzed by Indium TribromideEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2007Paola Vicennati Abstract Ferrocene derivatives have found many different uses and applications in organometallic chemistry, material chemistry, and catalysis. We have shown that using a catalytic amount (5,10 mol-%) of commercially available indium tribromide, at room temperature, many carbon nucleophiles, such as indoles, allylsilane, enolsilane, silyl ketene acetal, diketone, and trimethylsilylcyanide, smoothly react with different optically active ferrocenyl alcohol derivatives to afford the desired products in high yield, with retention of configuration. Also, many different N-nucleophiles (azide, carbamates) and O-nucleophiles (alcohols) react as well, again with retention of configuration. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Ring Opening of 1-Azabicyclo[1.1.0]butanes with Hydrazoic Acid , a Facile Access to N -Unsubstituted Azetidin-3-AminesHELVETICA CHIMICA ACTA, Issue 7 2005Grzegorz Mlosto Sterically congested 1-azabicyclo[1.1.0]butanes 1 add hydrazoic acid smoothly at 0,5°, giving 3-azidoazetidines 2 in good to excellent yields. After hydrogenolysis over Pd/C catalyst, compounds 2 were converted into N -unsubstituted azetidin-3-amines 4. Attempted reduction of 2a with Raney -Ni led to a mixture of the expected azetidin-3-amine 4a and the ring-enlarged 2,5-dihydro-1H -imidazole derivative 5. [source] Facile Access to an Efficient Solid-Supported Click Catalyst System Based on Poly(ethyleneimine)MACROMOLECULAR RAPID COMMUNICATIONS, Issue 1 2009Lies Bonami Abstract A novel heterogeneous copper(I) catalyst system, which is based on readily available poly(ethyleneimine), has been used as a recyclable catalyst for Cu(I) catalyzed "click" 1,3 dipolar cycloaddition reactions of azides and alkynes in organic media. Branched poly(ethyleneimine) was first methylated and then cross-linked with 1,9-dibromononane. Subsequently, after the immobilization of Cu(I)Br, this system was applied for heterogeneous copper catalyzed click chemistry of a few model reagents and polymeric compounds. [source] Catalytic Enantioselective Stereoablative Alkylation of 3-Halooxindoles: Facile Access to Oxindoles with C3 All-Carbon Quaternary Stereocenters,ANGEWANDTE CHEMIE, Issue 43 2009Sandy Ma Aus 2 mach 1! Racemische tertiäre Halogenoxindole gehen im Zuge einer stereoablativen enantioselektiven Katalyse in enantiomerenangereicherte Oxindole mit quartären Kohlenstoffstereozentren über (siehe Schema). Durch Anwendung dieses Prozesses gelingt der schnelle asymmetrische Aufbau biologisch wichtiger Alkaloid-Gerüste. [source] Acid-Catalyzed Intramolecular [2+2] Cycloaddition of Ene-allenones: Facile Access to Bicyclo[n.2.0] Frameworks,ANGEWANDTE CHEMIE, Issue 39 2009Jun-Feng Zhao Zwei plus zwei macht zwei Ringe: Eine hoch effiziente säurekatalysierte intramolekulare [2+2]-Cycloaddition von Enallenonen (siehe Schema; Tf: Trifluormethansulfonyl) ergibt unter milden Bedingungen gespannte Bicyclo[n.2.0]-Gerüste mit benachbarten quartären und tertiären Stereozentren in ausgezeichneten Ausbeuten und Chemo-, Regio- und Diastereoselektivitäten. [source] ChemInform Abstract: Asymmetric Epoxidation of 2-Arylidene-1,3-diketones: Facile Access to Synthetically Useful Epoxides.CHEMINFORM, Issue 43 2010Alessio Russo Abstract The first asymmetric epoxidation of title arylidenediketones, e.g. (I), (IV) or (VI), is presented. [source] ChemInform Abstract: Triethylamine-Catalyzed Domino Reactions of 1,3-Thiazolidinedione: A Facile Access to Functionalized Dihydrothiophenes.CHEMINFORM, Issue 8 2010Jing Sun 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 Enantioselective Stereoablative Alkylation of 3-Halooxindoles: Facile Access to Oxindoles with C3 All-Carbon Quaternary Stereocenters.CHEMINFORM, Issue 7 2010Sandy Ma 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: Consecutive Enolate Addition/Cyclization of Fischer Enynyl Carbene Complexes: Facile Access to Cyclopentenoids.CHEMINFORM, Issue 41 2009Jose Barluenga 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] Reaction of Salicyl N-Tosylimines with 2-Cyclohexenone: A Facile Access to Tetrahydroxanthenones.CHEMINFORM, Issue 8 2006Yong-Ling Shi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access the actual ChemInform Abstract, please click on HTML or PDF. [source] ChemInform Abstract: Domino Carbocationic Rearrangement of ,-[Bis(methylthio)methylene]alkyl-2-arylcyclopropyl Carbinols: Facile Access to 1-Arylindanes.CHEMINFORM, Issue 25 2001P. K. Mohanta 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] Addition of Azomethine Ylides to Aldehydes: Mechanistic Dichotomy of Differentially Substituted ,-Imino EstersEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 20 2010Brinton Seashore-Ludlow Abstract The formal 1,3-dipolar cycloaddition of azomethine ylides and aldehydes is explored, as hydrolysis of the resulting oxazolidine product gives facile access to valuable syn -,-aryl-,-hydroxy-,-amino esters. The use of using benzaldehyde-derived imines as the ylide precursor results in 1,3-dipolar cycloaddition with high conversions but low diastereoselectivity. In contrast, the employment of benzophenone-derived imines as the ylide precursor results in an aldol reaction, which gives the intermediate oxazolidine in high diastereoselectivity and requires a weak acid catalyst to achieve higher conversions. [source] A Facile and Efficient One-Pot Synthesis of Substituted Quinolines from ,-Arylamino Ketones Under Vilsmeier ConditionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2009Yan Wang Abstract An efficient one-pot synthesis of substituted quinolines from ,-arylamino ketones in the presence of PBr3 in DMF has been developed. This general protocol provides a novel and facile access to substituted quinolines by sequential Vilsmeier,Haack reaction, intramolecular cyclization and aromatization reactions of ,-arylamino ketones. PBr3 plays a dual role in the quinoline synthesis: as a key component of the Vilsmeier reagent (PBr3/DMF) and as a reducing reagent. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Odoriferous Cyclic Ethers via Co-Halogenation Reaction: Facile Preparation of Nerol Oxide, Florol®, Florol® Methyl Ether, and Pityol® Methyl EtherHELVETICA CHIMICA ACTA, Issue 1 2007Pankaj Gupta Abstract A series of odoriferous cyclic ethers, including nerol oxide (1), Florol® (2), Florol methyl ether (3), and Pityol® methyl ether (4b), were prepared by a versatile synthetic protocol based on co-halogenation with 1,3-dibromo-5,5-dimethylhydantoin (=,1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione; DDH) as the key step. The methodology provides a facile access to important perfumery molecules from abundantly available monoterpene alcohols. [source] Efficient palladium,ferrocenylphosphine catalytic systems for allylic amination of monoterpene derivativesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 12 2006Duc Hanh Nguyen Abstract Ferrocenylphosphines added to [Pd(µ-Cl)(,3 -C3H5)]2 dimeric precursor produce efficient catalysts to effect the allylic amination of terpenic allylacetates. Particularly convenient are tetrakis(diphenylphosphino)ferrocene and 1,1,-bis(diphenylphosphino)ferrocene, which allow the amination of allylacetates with good to excellent selectivity, and have turnover numbers as high as 80 000, for instance, for the formation of allylaniline. Herein, we report on reactions that selectively transform geranylacetate, nerylacetate, linalylacetate and perillylacetate into the corresponding allylic amines. These preparative methods give facile access to various products of great potential industrial interest. Copyright © 2006 John Wiley & Sons, Ltd. [source] ChemInform Abstract: Pentafluorophenylammonium Trifluoromethanesulfonimide: Mild, Powerful, and Robust Catalyst for Mukaiyama Aldol and Mannich Reactions Between Ketene Silyl Acetals and Ketones or Oxime Ethers.CHEMINFORM, Issue 38 2010Ryohei Nagase Abstract The catalyst allows facile access to ,-hydroxy esters, ,-amino esters, and 5-oxo esters. [source] ChemInform Abstract: Photoinduced Tandem Reactions of Isoquinoline-1,3,4-trione with Alkynes to Build Azapolycycles.CHEMINFORM, Issue 37 2010Haitao Yu Abstract Irradiation of isoquinoline (I) with alkynes allows facile access to various novel aza-polycycles. [source] | ||||||||||||||||||||||