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Highly Enantioselective Synthesis (highly + enantioselective_synthesis)

Distribution by Scientific Domains
Chemistry100%
Distribution within Chemistry
Organic Chemistry86%
General & Introductory Chemistry13%

Selected Abstracts

An Organocatalytic Domino Thia-Michael/Aldol Condensation Reaction: Highly Enantioselective Synthesis of Functionalized Dihydrothiophenes

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010
Jie Tang
Abstract An organocatalytic domino thia-Michael/aldol condensation reaction of ,, ,-unsaturated aldehydes with 1, 4-dithiane-2,5-diol catalyzed by chiral diphenylprolinol TMS ether has been developed, which provides a new practical and direct route to chiral dihydrothiophenes with high yields (up to 90%) and excellent enantioselectivities (up to>99% ee). The catalytic mechanism of the domino reaction was further confirmed through the APCI-MS detection of proposed reaction intermediates. [source]

Efficient Solvent-Free Robinson Annulation Protocols for the Highly Enantioselective Synthesis of the Wieland,Miescher Ketone and Analogues

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009
Ben Bradshaw
Abstract A highly efficient (93% overall yield) and enantioselective (94% ee) synthesis of the Wieland,Miescher ketone (10-g scale) through a solvent-free Robinson annulation procedure is reported. The process involves only 1,mol% triethylamine as the base in the initial Michael process and the organocatalyst N -tosyl-(Sa)-binam- L -prolinamide (2,mol%) and benzoic acid (0.5,mol%) for the intramolecular aldol process. This green protocol is applied to a wide range of valuable building block analogues of the Wieland,Miescher ketone (10 examples). Among these, a noteworthy compound for terpene synthesis is the 8a-allyl derivative, which is prepared in 93% yield and 97% ee in a process allowing the recovery and reutilization of the organocatalyst. Furthermore, a one-pot, two-step process has also been developed. [source]

Cooperative Catalysis in Multicomponent Reactions: Highly Enantioselective Synthesis of ,-Hydroxyketones with a Quaternary Carbon Stereocenter,

ANGEWANDTE CHEMIE, Issue 12 2010
Xiao-Yu Guan Dr.
Gemeinsam sind sie stark: Ein Aryldiazoacetat, H2O und ein ,,,-ungesättigtes 2-Acylimidazol reagieren mit ausgezeichneter Selektivität zu ,-Hydroxyketonen mit einem quartären Kohlenstoffstereozentrum, wenn alle drei im Schema gezeigten Katalysatorkomponenten vorhanden sind. Der Michael-Additionsschritt lief nicht ab, wenn eine ähnliche Reagensmischung nur mit dem [Rh2(OAc)4]-Katalysator behandelt wurde. OTf=Triflat, Ts=p -Tosyl. [source]

ChemInform Abstract: Catalytic Asymmetric Mannich,Ketalization Reaction: Highly Enantioselective Synthesis of Aminobenzopyrans.

CHEMINFORM, Issue 35 2010
Magnus Rueping
Abstract The reaction of o-hydroxy benzaldimines with electron-rich alkenes proceeds under mild conditions in the presence of an air-stable chiral catalyst and nicely complements Akiyama,s previously reported Broensted acid catalyzed reaction of aldimines with dihydrofurans and -pyrans leading to tetrahydroquinolines. [source]

ChemInform Abstract: Highly Enantioselective Synthesis of ,-Heteroaryl-Substituted Dihydrochalcones Through Friedel,Crafts Alkylation of Indoles and Pyrrole.

CHEMINFORM, Issue 22 2010
Wentao Wang
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: Chiral Primary,Secondary Diamines Catalyzed Michael,Aldol,Dehydration Reaction Between Benzoylacetates and ,,,-Unsaturated Ketones: Highly Enantioselective Synthesis of Functionalized Chiral Cyclohexenones.

CHEMINFORM, Issue 18 2010
Ying-Quan Yang
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: Highly Enantioselective Synthesis of Tertiary Alcohols: C2 -Symmetric N,N,-Dioxide-Sc(III) Complex Promoted Direct Aldol Reaction of ,-Ketoesters and Diazoacetate Esters.

CHEMINFORM, Issue 16 2010
Fei Wang
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: Highly Enantioselective Synthesis of Chiral Cyclic Amino Alcohols and Conhydrine by Ruthenium-Catalyzed Asymmetric Hydrogenation.

CHEMINFORM, Issue 11 2010
Sheng Liu
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: Highly Enantioselective Synthesis of 2-Furanyl-hydroxyacetates from Furans via the Friedel,Crafts Reaction.

CHEMINFORM, Issue 48 2008
Jakub Majer
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: Synthesis of C2 -Symmetric Sulfide and Its First Application in Highly Enantioselective Synthesis of Chiral Aziridines.

CHEMINFORM, Issue 19 2008
Yuan Gui
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]

Copper-Catalyzed Highly Enantioselective Synthesis of Cyclic Allylic and Homoallylic Alcohols with Dialkylzinc Reagents.

CHEMINFORM, Issue 28 2005
Mauro Pineschi
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

ChemInform Abstract: Electrophilic Fluorination Mediated by Cinchona Alkaloids: Highly Enantioselective Synthesis of ,-Fluoro-,-phenylglycine Derivatives.

CHEMINFORM, Issue 14 2002
Barbara Mohar
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: "Remote Stereocontrol" in Organocopper Chemistry: Highly Enantioselective Synthesis of Vinylallenes by 1,5-Substitution of Enyne Acetates.

CHEMINFORM, Issue 12 2001
Norbert Krause
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]

Direct Allylation of Aldimines Catalyzed by C2 -Symmetric N,N, -Dioxide,ScIII Complexes: Highly Enantioselective Synthesis of Homoallylic Amines

CHEMISTRY - A EUROPEAN JOURNAL, Issue 16 2008
Xing Li
The first catalytic asymmetric three-component allylation of aldimines has been developed. In the presence of L -ramipril acid-oriented N,N, -dioxide,ScIII complex catalyst, a range of homoallylic amines were formed in excellent enantioselectivities (up to 97,% ee) with good yields from corresponding aldehydes, 2-aminophenol and allyltributyltin (see scheme). [source]

Enantioselective Ag-Catalyzed Allylation of Aldimines,

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 30 2009
Marina Naodovic
Abstract A highly enantioselective synthesis of homoallylic amines, using allyltrimethoxysilane under AgI catalytic conditions, has been developed. Among the chiral ligands investigated, a remarkable difference in the resulting AgI complexes was observed. Under mild conditions and low catalyst loadings, homoallylamines were produced in high ee values (up to 80,%) and good yields. The methodology can be further extended to a diastere- and enantioselective crotylation of aldimines.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]