Stereochemical studies. LIX. Asymmetric transamination from (S)-.ALPHA.-amino acids. Synthesis of optically active amines by chemical transamination of (S)-.ALPHA.-amino acid esters to ketones.
Asymmetric Reaction of α-Diazomethylphosphonates with α-Ketoesters To Access Optically Active α-Diazo-β-hydroxyphosphonate Derivatives
作者:Fei Du、Jiao Zhou、Yungui Peng
DOI:10.1021/acs.orglett.7b00128
日期:2017.3.17
The first example for asymmetric reaction of diazomethylphosphonates with α-ketoesters was realized in the catalysis of hydroquinidine-derived bifunctional thiourea. A methodology was established to access a series of chiral α-diazo-β-hydroxyphosphonate derivatives containing various functional groups with high enantioselectivities and yields. The resulting products could be further transformed into
esters are important precursors of organocatalysts, pharmaceuticals, and biochemically interesting molecules. The organocatalyticasymmetric umpolung reaction of imines has been developed to obtain chiral amines in a highly enantioselective manner. Herein, we report the organocatalyticasymmetric umpolung synthesis of α‐amino‐δ‐keto esters in high yield (up to 95% ee, >20/1 r.r.).
Organocatalytic Highly Regio- and Enantioselective Umpolung Michael Addition Reaction of α-Imino Esters
作者:Yasushi Yoshida、Takashi Mino、Masami Sakamoto
DOI:10.1002/chem.201703479
日期:2017.9.18
The catalytic asymmetric umpolung reaction of ketimines is of great importance, because it can easily provide chiral amines bearing a tetrasubstitutedcarbon atom on its asymmetric center. Because amino acids with a tetrasubstitutedcarboncenter are useful due to their wide applicability as pharmaceuticals and chiral building blocks, their enantioselective synthesis has great significance in organic
METHOD FOR SYNTHESIS OF KETO ACIDS OR AMINO ACIDS BY HYDRATION OF ACETYLENE COMPOUND
申请人:Ogo Seiji
公开号:US20090216044A1
公开(公告)日:2009-08-27
An object of the present invention is to provide a method for synthesis of keto acids by hydration of an acetylene compound (acetylene-carboxylic acids) under mild conditions free from harmful mercury catalysts and a method for synthesis of amino acids from acetylene-carboxylic acids in a single container (one-pot or tandem synthesis). In one embodiment of the method according to the present invention for synthesis of keto acids, acetylene-carboxylic acids is hydrated in the presence of a metal salt represented by General Formula (1),
where M
1
represents an element in Group VIII, IX, or X of the periodic table, and X
1
, X
2
, or X
3
ligand represents halogen, H
2
O, or a solvent molecule, and k represents a valence of a cation species, and Y represents an anion species, and L represents a valence of the anion species, and each of K and L independently represents 1 or 2, and k×m=L×n.
Scandium-Catalyzed Electrochemical Synthesis of α-Pyridinyl Tertiary Amino Acids and Esters
作者:Feng Liu、Weijie Ding、Jiacong Lin、Xu Cheng
DOI:10.1021/acs.orglett.3c02734
日期:2023.10.27
α-Pyridyl tertiaryamino acids have potential pharmaceutical applications because of their structural features. However, their synthesis is still highly limited. Herein, we report a straightforward approach for the electrochemical synthesis of tertiary α-substituted amino acid derivatives via three-component reductive coupling. Using gaseous ammonia as both the N and H source, the α-keto ester reacts
α-吡啶基叔氨基酸由于其结构特征而具有潜在的药物应用。然而,它们的合成仍然非常有限。在此,我们报告了一种通过三组分还原偶联电化学合成叔α-取代氨基酸衍生物的简单方法。使用气态氨作为 N 源和 H 源,α-酮酯直接与 4-CN-吡啶反应。钪催化的应用是实现各种副反应途径化学选择性的关键。