Enantiopure Turbo Chirality Targets in Tri-Propeller Blades: Design, Asymmetric Synthesis, and Computational Analysis

Molecules, Год журнала: 2025, Номер 30(3), С. 603 - 603

Опубликована: Янв. 29, 2025

Enantiopure turbo chirality in small organic molecules, without other chiral elements, is a fascinating topic that has garnered significant interest within the chemical and materials science community. However, further research into application of this concept have been severely limited by lack effective asymmetric tools. To date, only few enantiomers targets isolated, these were obtained through physical separation using HPLC, typically on milligram scales. In work, we report first approach to enantiopure absence elements such as central axial chirality. This demonstrated assembling aromatic phosphine oxides, where three propeller-like groups are anchored P(O) center via axes. Asymmetric induction was successfully carried out sulfonimine auxiliary, with absolute configurations conformations unambiguously determined X-ray diffraction analysis. The resulting frameworks exhibit propellers arranged either clockwise (P,P,P) or counterclockwise (M,M,M) configuration. arrangements, bulkier sides rings oriented toward oxygen atom P=O bond rather than opposite direction. Additionally, orientational configuration controlled auxiliary well, showing one Naph pushed away from group (-CH2-NHSO2-tBu) phenyl ring. Computational studies conducted relative energies for rotational barriers target along axis transition pathway between two enantiomers, meeting our expectations. work expected impact fields chemistry, biomedicine, future.

Язык: Английский

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Discovery of Staircase Chirality through the Design of Unnatural Amino Acid Derivatives

Research, Год журнала: 2024, Номер 7

Опубликована: Янв. 1, 2024

Chirality has garnered significant attention in the scientific community since its discovery by Louis Pasteur over a century ago. It been showing profound impact on chemical, biomedical, and materials sciences. Significant progress made controlling molecular chirality, as evidenced several Nobel Prizes chemistry awarded this area, particularly for advancements asymmetric catalytic synthesis of molecules with central axial chirality. However, exploration new types chirality largely stagnant more than half century, likely due to complexity challenges inherent field. In work, we present novel type chirality—staircase inspired design unnatural amino acid derivatives. The architecture staircase is characterized 2 symmetrical phenyl rings anchored naphthyl pier, asymmetrically displaced influence chiral auxiliaries at their para positions. This unique framework thoroughly using spectroscopic techniques, absolute configuration definitively confirmed x-ray diffraction analysis. Remarkably, one exhibits 4 distinct chirality: central, orientational, turbo, combination that not previously documented literature. Computational studies density functional theory (DFT) calculations were conducted analyze relative energies individual isomers, results are agreement our experimental findings. We believe will open up research frontier catalysis, potential make substantial fields chemistry, medicine, science.

Язык: Английский

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Pd/Cu-Cocatalyzed Asymmetric Cascade Heck/Tsuji–Trost Reaction to Access Non-natural Tryptophans

Organic Letters, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 20, 2024

A Pd-catalyzed asymmetric Heck cascade reaction involving the intramolecular carbopalladation of unsaturated hydrocarbons, followed by nucleophilic trapping resulting palladium species, is a powerful approach for constructing chiral N-heterocycles. However, use prochiral nucleophiles in these reactions remains significantly underexplored. Herein, we report novel Pd/Cu catalytic system Heck/Tsuji–Trost allenamides and aldimine esters. This robust method allows rapid synthesis wide range enantiopure non-natural α-substituted tryptophans high yields (up to 99% yield) with excellent enantioselectivities 98% ee). Additionally, synthetic utility this protocol demonstrated through scale-up experiments diverse valuable transformations.

Язык: Английский

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Enantioselective Vinylogous Addition of Enones to Allenes Enabled by Synergistic Borane/Palladium Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Дек. 24, 2024

Herein, we report a method for enantioselective vinylogous addition of enones to alkoxyallenes enabled by synergistic borane/palladium catalysis. The inductive effect provided borane coordination the ketone was essential closing gap between conditions needed generation dienolate and those initiation palladium catalytic cycle protonation metal catalyst. Furthermore, accomplished first example stereodivergent synthesis with chiral borane/transition-metal catalysts.

Язык: Английский

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