Sequential Michael addition, cross-coupling and [3 + 2] cycloaddition reactions within the coordination sphere of chiral Ni(ii) Schiff base complexes derived from dehydroamino acids: pathways to the asymmetric synthesis of structurally diverse O-substituted serine and threonine analogs

RSC Advances, Journal Year: 2025, Volume and Issue: 15(14), P. 10558 - 10564

Published: Jan. 1, 2025

An approach to the synthesis of a series novel, enantiomerically pure analogs β-hydroxy-α-amino acids is reported.

Language: Английский

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Direct synthesis of spirooxindoles enabled by palladium-catalyzed allylic alkylation and DBU-mediated cyclization: concept, scope and applications

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(19), P. 5443 - 5453

Published: Jan. 1, 2024

A concise construction of spiro[indoline-3,2′-pyrrol]-2-one skeletons is reported. This reaction proceeded through a palladium-catalyzed decarboxylative allylic alkylation followed by DBU-mediated intramolecular cyclization.

Language: Английский

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Synthesis of enantiomerically enriched β-substituted analogs of (S)-α-alanine containing 1-phenyl-1H-1,2,3-triazole groups

Amino Acids, Journal Year: 2024, Volume and Issue: 56(1)

Published: Dec. 3, 2024

A synthesis of new enantiomerically enriched derivatives (S)-α-aminopropionic acid, containing in the β-position 1,2,3-triazole groups coupled with a o-, m- and p-substituted phenyl residue, was developed based on Cu(I) catalyzed [3 + 2] cycloaddition azides alkynes. As starting materials used square-planar Ni(II)complex Schiff base propargylglycine chiral auxiliary BPB (Benzylprolylbenzophenone) 1,4-substituted azides. The assignment (S)-absolute configuration α-carbon atom amino acid residue main diastereomeric complexes products carried out basis positive Cotton effects region 480–580 nm circular dichroism spectra. target acids were isolated from hydrolysates using ion-exchange demineralization crystallization aqueous ethanol. Additional confirmation absolute determination enantiomeric purity by HPLC analysis. result, seven non-proteinogenic (S)-α-amino acids, moiety, synthesized.

Language: Английский

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N‐Heterocyclic Carbene‐Catalyzed Enantioselective Synthesis of Spirocyclohexane Oxindoles

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 17, 2024

Abstract A variety of structurally diverse spirocyclohexane oxindoles featuring a quaternary carbon centre have been successfully constructed through an N‐heterocyclic carbene‐catalyzed [4+2] annulation isatin‐derived enals with α ‐cyano‐ β ‐methylenones. This domino process exhibits wide substrate tolerance, operates under mild conditions, and yields products high enantioselectivities.

Language: Английский

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A Radical Hydrohaloalkylation of the Ligand Sphere of a Chiral Dehydroalanine Ni(II) Complex: An Asymmetric Route to Halogenated α-Amino Acid Derivatives

Tetrahedron Chem, Journal Year: 2024, Volume and Issue: unknown, P. 100118 - 100118

Published: Dec. 1, 2024

Language: Английский

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Chiral Ni(II) Dehydroalanine Complex in the Michael 1,4-Addition Reaction with Tryptanthrin CF3-Derivative

Russian Journal of General Chemistry, Journal Year: 2024, Volume and Issue: 94(12), P. 3234 - 3240

Published: Dec. 1, 2024

Language: Английский

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