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Diastereoselective Addition (diastereoselective + addition)

Distribution by Scientific Domains
Chemistry100%

Kinds of Diastereoselective Addition

  • highly diastereoselective addition
    		•

    Selected Abstracts

    Synthesis of Enantiopure 1-Aryl-1-butylamines and 1-Aryl-3-butenylamines by Diastereoselective Addition of Allylzinc Bromide to Imines Derived from (R)-Phenylglycine Amide

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 7 2004
    Jan Dalmolen
    Abstract The synthesis of enantiopure 1-aryl-1-butylamines via a highly diastereoselective addition of allylzinc bromide to imines derived from (R)-phenylglycine amide is reported. These are synthesised by a three-step procedure, which involves: (a) formation of the chiral imines; (b) asymmetric addition of the allylzinc reagent; (c) removal of the chiral auxiliary by means of a reductive or non-reductive method. The reductive method provides 1-aryl-1-butylamines whereas the non-reductive method preserves the double bond to afford 1-aryl-3-butenylamines. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source]

    ChemInform Abstract: Highly Diastereoselective Addition of Alkynylmagnesium Chlorides to N-tert-Butanesulfinyl Aldimines: A Practical and General Access to Chiral ,-Branched Amines.

    CHEMINFORM, Issue 22 2010
    Bai-Ling Chen
    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 Diastereoselective Addition of Allyltitanocenes to Ketones.

    CHEMINFORM, Issue 28 2009
    Yasutaka Yatsumonji
    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]

    An Efficient Synthesis of Enantiomerically Enriched Trifluoromethylated 1,2-Diols and 1,2-Amino Alcohols with Quaternary Stereocenters by Diastereoselective Addition of TMSCF3 to Chiral 2-Acyl-1,3-perhydrobenzoxazines.

    CHEMINFORM, Issue 28 2006
    Rafael Pedrosa
    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]

    Diastereoselective Addition of Nitro Compounds to ,,,-Unsaturated ,-Butyrolactones.

    CHEMINFORM, Issue 17 2006
    Giovanni B. Rosso
    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]

    Diastereoselective Addition of Organozinc Reagents to 2-Alkyl-3-(arylsulfanyl)propanals.

    CHEMINFORM, Issue 9 2005
    Michael Larsson
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]

    Rapid, Highly Diastereoselective Addition of Dialkylzinc Reagents to Atropisomeric 2-Formyl Arylamides.

    CHEMINFORM, Issue 36 2004
    Ciril Jimeno
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]

    Highly Diastereoselective Addition of Et2AlCN to ,-Keto Amides Derived from (S)-4-Isopropyl-2-oxazolidinone.

    CHEMINFORM, Issue 2 2004
    Virginia Flores-Morales
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]

    First Synthesis of Optically Pure Propargylic N-Hydroxylamines by Direct, Highly Diastereoselective Addition of Terminal Alkynes to Nitrones.

    CHEMINFORM, Issue 51 2002
    Roger Faessler
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]

    ChemInform Abstract: Diastereoselective Addition of Chiral Azomethine Ylides to Cyclic ,,,-Unsaturated N-Enoylbornanesultams.

    CHEMINFORM, Issue 34 2002
    Staffan Karlsson
    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: Sc(OTf)3 -Catalyzed Diastereoselective Addition of Enol Silanes and Silyl Ketene Acetals to Cr(CO)3 -Complexed Aryl Aldimines.

    CHEMINFORM, Issue 29 2002
    Bikash C. Maity
    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]

    Diastereoselective Additions of Chiral Vinylzinc Reagents to ,-Chiral Aldehydes.

    CHEMINFORM, Issue 24 2004
    James A. Marshall
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]

    Asymmetric Total Synthesis of (+)-6- epi -Castanospermine by the Stereoselective Formation of a syn,anti Acetylenic 2-Amino-1,3-diol Stereotriad

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2010
    Julien Louvel
    Abstract The asymmetric total synthesis of (+)-6- epi -castanospermine (1) is described herein. In this synthesis the diastereoselective addition of a racemic allenylzinc reagent to an enantiopure ,-alkoxy- tert -butylsulfinylimine is the key step and is followed by the formation of a piperidine ring by ring-closing metathesis and subsequent syn -dihydroxylation of an alkene. [source]

    Asymmetric Synthesis of ES-285, an Anticancer Agent Isolated from Marine Sources

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 35 2009
    Ana C. Allepuz
    Abstract The asymmetric synthesis of (2S,3R)-2-amino-3-octanedecanol hydrochloride (ES-285·HCl) was achieved in eight steps in ca. 38,% overall yield from the N -benzylimine-derived from (R)-2,3- O -isopropylidene glyceraldehyde, which is easily available on gram scale from the inexpensive precursor D -mannitol. Highly diastereoselective addition of methylmagnesium bromide to the N -benzylimine was the key step to create the vic -amino alcohol moiety with the appropriate configuration. Regioselective ring opening of an intermediate aminoepoxide enabled the introduction of the long hydrocarbon chain at C4.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]

    Synthesis of Enantiopure 1-Aryl-1-butylamines and 1-Aryl-3-butenylamines by Diastereoselective Addition of Allylzinc Bromide to Imines Derived from (R)-Phenylglycine Amide

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 7 2004
    Jan Dalmolen
    Abstract The synthesis of enantiopure 1-aryl-1-butylamines via a highly diastereoselective addition of allylzinc bromide to imines derived from (R)-phenylglycine amide is reported. These are synthesised by a three-step procedure, which involves: (a) formation of the chiral imines; (b) asymmetric addition of the allylzinc reagent; (c) removal of the chiral auxiliary by means of a reductive or non-reductive method. The reductive method provides 1-aryl-1-butylamines whereas the non-reductive method preserves the double bond to afford 1-aryl-3-butenylamines. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source]

    Computational Investigations on the General Reaction Profile and Diastereoselectivity in Sulfur Ylide Promoted Aziridination

    CHEMISTRY - A EUROPEAN JOURNAL, Issue 17 2007
    Deepa Janardanan
    Abstract Mechanism and diastereoselectivity of sulfur ylide promoted aziridination reactions were studied by density functional theory with inclusion of solvent effects through the continuum solvation model. The general reaction pathway was modeled for the addition of substituted sulfur ylides (Me2S+CH,R) to an aldimine ((E)-methyl ethylidenecarbamate, MeHCNCO2Me). The nature of the substituents on the ylidic carbon atom substantially affects the reaction profile. The stabilized (R=COMe) and semistabilized (R=Ph) ylides follow a cisoid addition mode leading to trans aziridines via anti betaine intermediates. The simplest model ylide (unstabilized, R=H) underwent cisoid addition in a similar fashion. In the case of stabilized ylides product diastereoselectivity is controlled by the barriers of the elimination step leading to the 2,3- trans aziridine, whereas it is decided in the addition step in the case of semistabilized ylides. The importance of steric and electronic factors in diastereoselective addition (2 and 5) and elimination (5) transition states was established. Comparison of results obtained with the gas-phase optimized geometries and with the fully optimized solvent-phase geometries reveals that the inclusion of solvent effects does not bring about any dramatic changes in the reaction profiles for all three kinds of ylides. In particular, diastereoselectivity for both kinds of ylides was found to be nearly the same in both these approaches. [source]

    Syntheses of New Chiral Phosphane Ligands by Diastereoselective Conjugate Addition of Phosphides to Enantiomerically Pure Acceptor-Substituted Olefins from the Chiral Pool

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2005
    Burkhard Wiese
    Abstract A variety of new chiral phosphanes were prepared by highly diastereoselective additions of phosphanes to ,,,-unsaturated carbonyl compounds and related acceptor-substituted olefins derived from myrtenal as ex chiral pool source. Monophosphanes with astereogenic as well as stereogenic phosphorus are described. In addition diphosphanes were prepared by a highly diastereoselective double conjugate addition of a secondary diphosphane. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]