22260-39-5

Upstream product

• 122885-25-0 2-(Benzhydrylidene-amino)-hexa-4,5-dienoic acid methyl ester 
• 735252-89-8 2-amino-4,5-hexadienoic acid amide 

Relevant academic research and scientific papers

Synergistic Cu/Pd-Catalyzed Asymmetric Allenylic Alkylation of Azomethine Ylides for the Construction of α-Allene-Substituted Nonproteinogenic α-Amino Acids

An unprecedented asymmetric allenylic alkylation of readily available imine esters, which was enabled by a synergistic Cu/Pd catalysis, has been developed. This dual catalytic system possesses good substrate compatibility, delivering a diverse array of nonproteinogenic α-allenylic α-mono- or α,α-disubstituted α-amino acids (α-AAs) with high yields and generally excellent enantioselectivities. Furthermore, the scalability and practicability of the current synthetic protocol were proven by performing gram-scale reactions and by the first catalytic asymmetric synthesis of naturally occurring (S)-γ-allenic α-amino acid, respectively.

Allene Transfer Reactions. A New Synthesis of Terminal Allenes.

Alkyl radicals, produced from alkyl bromides and iodides, react smoothly with triphenylprop-2-ynylstannane to provide terminal allenes; this new reaction has been applied to a simple and stereospecific synthesis of the naturally occurring allenic amino ac

One Stone Two Birds—Enantioselective Bimetallic Catalysis for α-Amino Acid Derivatives with an Allene Unit

A highly enantioselective 2,3-allenylation of acyclic and cyclic α-imino carboxylates via a synergistic bimetallic Pd/Cu catalysis with the same commercially available (R,Rp)-iPr-FOXAP (also as Phosferrox, (R,R)-[2-(4’-i-propyloxazolin-2’-yl)ferrocenyl]diphenyl phosphine) ligand for both metals affording optically active 2,3-butadienyl α-amino acid derivatives in high to excellent yields with excellent enantioselectivities has been developed. The synthetic versatility of this reaction has been demonstrated by gram-scale synthesis, a catalytic enantioselective synthesis of naturally occurring (S)-2-amino-4,5-hexadienoic acid A, and conversions to several useful chemicals, such as optically active α-amino acids, β-amino alcohols, potential chiral oxazoline ligands bearing an allenic moiety, and bicyclic ketone compounds. A mechanism involving the roles of two metals and the single chiral ligand has been extensively studied based on the isolation of key palladium pre-catalyst and control experiments.

A Biocatalytic Route to Enantiomerically Pure Unsaturated α-H-α-Amino Acids

A set of both enantiomeric forms of non-proteinogenic, unsaturated α-H-α-amino acids was efficiently synthesized using a biocatalytic pathway. This route involved the straightforward synthesis of the required unsaturated amino acid amides, followed by resolution with an aminopeptidase present in Pseudomonas putida ATCC 12633 and/or a genetically modified organism, leading to the (S)-acids and (R)-amides. Undesired amino acid racemase activity was identified in the wild-type strain, which was absent in the newly developed organism. The (R)-amides were hydrolyzed under mild conditions using an amidase present in whole cells from Rhodococcus erythropolis NCIMB 11540 to the (R)-acids. The viability of this procedure was demonstrated with the multi-gram synthesis of a variety of unsaturated amino acids in excellent enantiopurity.

Selective azetidine and tetrahydropyridine formation via Pd-catalyzed cyclizations of allene-substituted amines and amino acids

Formula presented By choosing the right substituents either highly functionalized unusual four-membered ring amino acids or the isomeric pipecolic acid derivatives are obtained in enantiomerically pure form. Starting material is a linear allene-containing amino acid that has been resolved via biocatalysis.