Nucleophilic Glycine Research Articles

Highly Diastereoselective Michael Addition Reactions between Nucleophilic Glycine Equivalents and β-substituted-α,β-Unsaturated Carboxylic acid Derivatives a General Approach to the Stereochemically Defined and Sterically χ-Constrained α-Amino Acids

Highly Diastereoselective Michael Addition Reactions between Nucleophilic Glycine Equivalents and β-substituted-α,β-Unsaturated Carboxylic acid Derivatives a General Approach to the Stereochemically Defined and Sterically χ-Constrained α-Amino Acids

Chiral nucleophilic glycine and alanine synthons: nickel(II) complexes of Schiff bases of ( S )- N -(2,4,6-trimethylbenzyl)proline (2-benzoylphenyl)amide and glycine or alanine

A new chiral auxilliary, (S)-N-(2,4,6-trimethylbenzyl)proline (2-benzoylphenyl)amide, has been synthesised as a potential building block for the preparation of chiral synthons of amino acids. The nickel(II) complex of its Schiff base derivative with glycine has been methylated with 97% d.e. (diastereomeric excess), whilst the nickel(II) complex of its Schiff base derivative with (RS)alanine has been 13C-methylated with 66% d.e.

Large-scale asymmetric synthesis of novel sterically constrained 2′,6′-dimethyl- and α,2′,6′-trimethyltyrosine and -phenylalanine derivatives via alkylation of chiral equivalents of nucleophilic glycine and alanine

Asymmetric synthesis of ( S)-2′,6′-dimethyltyrosine (DMT), ( S)-2′,6′-dimethylphenylalanine (DMP), ( S)-α,2′,6′-trimethyltyrosine (α-TMT) and ( S)-α,2′,6′-trimethylphenylalanine (α-TMP) via reactions of 4′-benzyloxy-2′,6′-dimethylbenzyl bromide or 2′,6′-dimethylbenzylbromide with Ni(II)-complexes of the chiral Schiff base of glycine or alanine with ( S)- o-[ N-( N-benzylprolyl)amino]benzophenone were developed. Inexpensive and readily available reagents and solvents, a recyclable chiral auxiliary, simplicity of the experimental procedures and high chemical yields make this method synthetically attractive for preparing the target amino acids on a multi-gram scale.

Rational design of highly diastereoselective, organic base-catalyzed, room-temperature Michael addition reactions.

Via the rational design of a single-preferred transition state, stabilized by electron donor-acceptor-type attractive interactions, structural and geometric requirements for the corresponding starting compounds have been determined. The Ni(II) complex of the Schiff base of glycine with o-[N-alpha-picolylamino]acetophenone, as a nucleophilic glycine equivalent, and N-(trans-enoyl)oxazolidin-2-ones, as derivatives of an alpha,beta-unsaturated carboxylic acid, were found to be the substrates of choice featuring geometric/conformational homogeneity and high reactivity. The corresponding Michael addition reactions were found to proceed at room temperature in the presence of catalytic amounts of DBU to afford quantitatively the addition products with virtually complete diastereoselectivity. Acidic decomposition of the products followed by treatment of the reaction mixture with NH4OH gave rise to the diastereomerically pure 3-substituted pyroglutamic acids.

Convenient, asymmetric synthesis of enantiomerically pure 2′,6′-dimethyltyrosine (DMT) via alkylation of chiral equivalent of nucleophilic glycine

Asymmetric synthesis of ( S)-2′,6′-dimethyltyrosine (DMT) via reactions of 4′-benzyloxy-2′,6′-dimethylbenzyl bromide with Ni(II)-complexes of the chiral Schiff base of glycine with ( S)- o-[ N-( N-benzylprolyl)amino]benzophenone was developed. Inexpensive and readily available reagents and solvents involved, including recyclable chiral auxiliary, simplicity of the experimental procedures and high chemical yields, make this method synthetically attractive for preparing the target amino acids on a multi-gram scale.

Toward design of a practical methodology for stereocontrolled synthesis of χ-constrained pyroglutamic acids and related compounds. Virtually complete control of simple diastereoselectivity in the Michael addition reactions of glycine Ni(II) complexes with N-(enoyl)oxazolidinones

A Ni(II) complex of the Schiff base of glycine with o-[ N-α-picolylamino]benzophenone or -acetophenone as a nucleophilic glycine equivalent, and N- trans-enoyloxazolidinones, as a derivative of an α,β-unsaturated carboxylic acid, were found to be the substrates of choice in the corresponding Michael addition reactions. The reactions proceed at room temperature in the presence of catalytic amounts of DBU to afford quantitatively a virtually diastereocomplete formation of the corresponding addition products with (2 R*,3 R*) or (2 R*,3 S*) relative configuration, depending on the nature of the starting N-enoyloxazolidinones. Acidic decomposition of the products followed by treatment of the reaction mixture with NH 4OH gives rise to the corresponding diastereomerically pure 3-substituted pyroglutamic acids.

ChemInform Abstract: N,O Highly Regio‐ and Stereoselective Alkylation of Nucleophilic Glycine Equivalents with Carbonates of Allylic α‐ Hydroxyphosphonates: A Convenient Route to Racemic 2‐Amino‐5‐phosphono‐ 4‐pentenoic Acids.

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Highly regio‐ and stereoselective alkylation of nucleophilic glycine equivalents with carbonates of allylic α‐hydroxyphosphonates: A convenient route to racemic 2‐amino‐5‐phosphono‐4‐pentenoic acids

Liebigs AnnalenVolume 1997, Issue 9 p. 2003-2003 CorrectionFree Access Highly regio- and stereoselective alkylation of nucleophilic glycine equivalents with carbonates of allylic α-hydroxyphosphonates: A convenient route to racemic 2-amino-5-phosphono-4-pentenoic acids Elisabeth Öhler, Elisabeth ÖhlerSearch for more papers by this authorSilvia Kanzler, Silvia KanzlerSearch for more papers by this author Elisabeth Öhler, Elisabeth ÖhlerSearch for more papers by this authorSilvia Kanzler, Silvia KanzlerSearch for more papers by this author First published: August 22, 1997 https://doi.org/10.1002/jlac.199719970929AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume1997, Issue9August 22, 1997Pages 2003-2003 RelatedInformation

N,O Highly Regio‐ and Stereoselective Alkylation of Nucleophilic Glycine Equivalents with Carbonates of Allylic α‐Hydroxyphosphonates: A Convenient Route to Racemic 2‐Amino‐5‐phosphono‐4‐pentenoic Acids

AbstractPalladium(0)‐catalyzed allylic alkylation of diethyl (acetyl‐amino)malonate (6), ethyl (diphenylmethyleneamino)acetate (7), and (diphenylmethyleneamino)acetonitrile (8), respectively, with the acrolein‐derived 1‐dialkoxyphosphinyl‐substituted carbonates 5 provides the γ‐substituted vinylphosphonates 9–11 in very good yields and with high regioselectivity. The stereochemical outcome is dependent on the mode of nucleophilic activation of the glycine equivalents 6–8: When the reactions are performed in the presence of N,O‐bis(trimethylsilyl)acetamide (BSA) the (Z) isomers (Z)‐9–(Z)‐11 are highly favoured, while in the absence of any additional activation of the nucleophiles the corresponding (E) isomers predominate. In the latter case, upon alkylation of the Schiff base derivatives 7 and 8, up to 30% of the α‐substitution products 12 and 13, respectively, are isolated as by‐products. The vinylphosphonates 9–11 are easily converted to the racemic 2‐amino‐5‐phosphono‐4‐pentenoic acids (Z)‐3 and (E)‐3, and to the saturated analogue 1.