Atroposelective Synthesis of Axially Chiral Diaryl Ethers by Copper-Catalyzed Enantioselective Alkyne–Azide Cycloaddition

ACS Catalysis, Год журнала: 2024, Номер 14(5), С. 3475 - 3481

Опубликована: Фев. 21, 2024

Diaryl ethers are important structural motifs widely found in bioactive natural products, ligands, and catalysts. While there a variety of methods available to generate diaryl ethers, progress on the construction axially chiral has been slow. We report herein an atroposelective copper-catalyzed cycloaddition between bisalkynes azides. With indane-fused BOX ligand used, diverse array C–O atropisomers obtained with up 97% yield 99% ee. Control experiments showed that sequential enantioselective desymmetrization–kinetic resolution process is involved, former plays major role. In addition, asymmetric depletion observed for this catalytic synthesis by nonlinear effect studies. By thermal racemization experiments, rotational barrier axis 3aa calculated be 35.9 kcal/mol, which lays foundation its isolation, as well further applications.

Язык: Английский

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Construction of Ge-Stereogenic Center by Desymmetric Carbene Insertion of Dihydrogermanes

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(8), С. 5643 - 5649

Опубликована: Фев. 8, 2024

We developed a method for the enantioselective synthesis of germanium-stereogenic compounds by desymmetric carbene insertion dihydrogermanes. A chiral rhodium phosphate catalyst decomposes diaryldiazo-methanes to generate carbenes that insert enantioselectively into one two Ge–H bonds dihydrogermanes form under mild reaction conditions. By this method, variety germanes with centers were synthesized in high yields and excellent enantioselectivities. Kinetic studies showed diazo decomposition process was rate-determining step. The remaining bond germane products provides possibility preparing tetra-substituted compounds.

Язык: Английский

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Boron‐Based Enantiomerism

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(14)

Опубликована: Март 7, 2024

Abstract Boron‐based enantiomerism is fragile due to the inherent tendency of a dissociation ligand from tetra‐coordinate chiral boron complexes under formation achiral tri‐coordinate species. This review will present different approaches in overcoming racemization boron‐stereogenic compounds. When embedded an environment ligands or substituents, configurationally stable stereogenic centers can form diastereoselective manner. Compounds incorporating as exclusive center are obtained by resolution racemic mixtures. The recently developed – much more efficient methods catalytic, enantioselective creation compounds highlighted this review. Finally chiroptical properties enantiomerically pure that makes them promising materials devices addressed.

Язык: Английский

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Modular enantioselective assembly of multi-substituted boron-stereogenic BODIPYs

Nature Chemistry, Год журнала: 2024, Номер 17(1), С. 83 - 91

Опубликована: Сен. 20, 2024

Язык: Английский

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Construction of boron-stereogenic compounds via enantioselective Cu-catalyzed desymmetric B–H bond insertion reaction

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Май 12, 2022

Abstract Compared with the well-developed carbon-stereogenic chemistry, construction of boron-stereogenic compounds remains undeveloped and challenging. Herein, previously elusive catalytic enantioselective has been achieved through desymmetric B–H bond insertion reaction. The reaction 2-arylpyridine-boranes versatile diazo under chiral copper catalyst can afford good to excellent enantioselectivity. Moreover, synthetic utility this is demonstrated by scalability downstream transformations. DFT calculations provide insights into mechanism origin stereoselectivity.

Язык: Английский

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Stepwise Asymmetric Allylic Substitution‐Isomerization Enabled Mimetic Synthesis of Axially Chiral B,N‐Heterocycles

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(51)

Опубликована: Окт. 25, 2022

Axially chiral molecules bearing multiple stereogenic axes are of great importance in the field organic chemistry. However, efficient construction atropisomers featuring two different types has rarely been explored. Herein, we report novel atroposelective synthesis configurationally stable axially B,N-heterocycles. By using stepwise asymmetric allylic substitution-isomerization (AASI) strategy, diaxially B,N-heterocycles B-C and C-N that related to moieties enamines arylborons were also obtained. In this case, all four stereoisomers stereodivergently afforded high enantioselectivities. Density functional theory (DFT) studies demonstrated NH⋅⋅⋅π interactions played a unique role promotion stereospecific isomerization, thereby leading highly central-to-axial chirality transfer.

Язык: Английский

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Synthesis of a Blue‐Emissive Azaborathia[9]helicene by Silicon‐Boron Exchange from Unusual Atropisomeric Teraryls

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(30)

Опубликована: Май 13, 2023

We report the concise synthesis and chir(optical) properties of an azaborathia[9]helicene consisting two thienoazaborole motifs. The key intermediate, a highly congested teraryl with nearly parallel isoquinoline moieties, was generated as mixture atropisomers upon fusion central thiophene ring dithienothiophene moiety. These diastereomers were characterized by single crystal X-ray analysis revealing intriguing interactions in solid state. Subsequent insertion boron into aromatic scaffold via silicon-boron exchange involving triisopropylsilyl groups fixed helical geometry, thereby establishing novel method for preparation azaboroles. ligand at final step afforded blue emitter displaying fluorescence quantum yield 0.17 CH2 Cl2 excellent configurational stability. Detailed structural theoretical investigation unusual helicene provide insights their isomerization processes.

Язык: Английский

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Amino Acid-Derived Ionic Chiral Catalysts Enable Desymmetrizing Cross-Coupling to Remote Acyclic Quaternary Stereocenters

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(30), С. 16796 - 16811

Опубликована: Июль 20, 2023

Synthetic application of asymmetric catalysis relies on strategic alignment bond construction to creation chirality a target molecule. Remote desymmetrization offers distinctive advantages spatial decoupling catalytic transformation and generation stereogenic element. However, such separation presents substantial difficulties for the chiral catalyst discriminate distant enantiotopic sites through reaction three or more bonds away from prochirality center. Here, we report strategy that establishes acyclic quaternary carbon stereocenters cross-coupling reactions at distal positions aryl substituents. The new class amino acid-derived ionic catalysts enables desymmetrizing (enantiotopic-group-selective) Suzuki-Miyaura reaction, Sonogashira Buchwald-Hartwig amination between diverse diarylmethane scaffolds aryl, alkynyl, coupling partners, providing rapid access enantioenriched molecules project substituents widely spaced in three-dimensional space. Experimental computational investigations reveal electrostatic steering substrates by C-terminus ligands interactions. Cooperative ion-dipole interactions catalyst's amide group potassium cation aid preorganization transmits asymmetry product. This study demonstrates it is practical achieve precise long-range stereocontrol engineering arrangements catalysts' substrate-recognizing groups metal centers.

Язык: Английский

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Catalytic Enantioselective Azide–Alkyne Cycloaddition Chemistry Opens Up New Prospects for Chiral Triazole Syntheses

ACS Catalysis, Год журнала: 2023, Номер 13(9), С. 6301 - 6311

Опубликована: Апрель 24, 2023

Catalytic enantioselective azide–alkyne cycloaddition (E-AAC) is a highly efficient click technology for the construction of structurally diverse chiral triazoles, which have broad applications in fields synthetic chemistry, medicinal biological and materials science. The past six years seen impressive developments copper-, nickel-, iridium-, rhodium-catalyzed E-AAC reactions. This review provides brief summary on this evolution according to different strategies implemented.

Язык: Английский

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Boron‐Stereogenic Compounds: Synthetic Developments and Opportunities

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(19), С. 2401 - 2411

Опубликована: Май 27, 2024

Comprehensive Summary The 21 st century has witnessed a continuous evolution in the development of boron‐stereogenic chemistry. Since 1990s, various innovations for synthesis tetracoordinate compounds, which exhibited great potential applications, have been demonstrated by synthetic chemists. This paper reviews significant progress and recent advances towards assembly enantioenriched hopes to shed light on new perspectives inspire further research this emerging field.

Язык: Английский

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