An overview of the applications of chiral phosphoric acid organocatalysts in enantioselective additions to CO and CN bonds

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(22), С. 6331 - 6399

Опубликована: Янв. 1, 2022

Since 2004, chiral phosphoric acids (CPAs) have emerged as highyl efficient organocatalysts, providing excellent results in a wide reaction scope. In this review, the applications of CPA for enantioselective additions to CO and CN bonds are covered.

Язык: Английский

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Asymmetric aza‐Friedel–Crafts Reaction of Cyclic Ketimines with 5‐Aminopyrazole Derivatives: Expedient Access to Pyrazole‐Based C2‐quaternary Indolin‐3‐Ones

Chemistry - A European Journal, Год журнала: 2023, Номер 29(20)

Опубликована: Янв. 5, 2023

A chiral phosphoric acid-catalyzed enantioselective aza-Friedel-Crafts reaction of 5-aminopyrazole derivatives with cyclic ketimines attached to a neutral functional group is reported. This protocol allows the formation pyrazole-based C2-quaternary indolin-3-ones high enantioselectivities and regioselectivities. Moreover, gram-scale synthesis 5-aminopyrazole-based was performed, no decrease in yield enantioselectivity.

Язык: Английский

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Chiral Phosphoric Acid-Catalyzed Enantioselective Dearomative Electrophilic Hydrazination: Access to Chiral Aza-Quaternary Carbon Indolenines

ACS Catalysis, Год журнала: 2022, Номер 12(13), С. 7511 - 7516

Опубликована: Июнь 9, 2022

Direct enantioselective synthesis of chiral aza-quaternary carbon indolenines through the dearomative electrophilic hydrazination 2,3-disubstituted indoles has been achieved. This catalytic asymmetric strategy leads to efficient construction a series enantioenriched in high yields and excellent stereoselectivities. The synthetic practicality this reaction demonstrated by modification derivatization drug molecules. In-situ infrared density functional theory calculations suggest that our system could overcome background achieve effective dearomatization.

Язык: Английский

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Accessing unnatural α-amino acids with tetrasubstituted stereogenic centersviacatalytic enantioselective reactions of ketimine-type α-iminoesters/α-iminoamides

Chemical Communications, Год журнала: 2023, Номер 59(54), С. 8343 - 8374

Опубликована: Янв. 1, 2023

Catalytic enantioselective synthesis methodologies have been actively explored and developed owing to the significance of chiral molecules their utilities. In particular, unnatural α-amino acids with tetrasubstituted stereogenic carbon centers (α-tertiary amino acids; ATAAs) are undoubtedly among most valuable compounds. Asymmetric addition an α-iminoester or α-iminoamide is widely recognized as a straightforward, powerful, atom-economical strategy for accessing optically active derivatives. However, this type chemistry, which relies on ketimine-type electrophiles, was quite limited only few decades ago low reactivities difficulties associated enantiofacial control. This feature article comprehensively overviews research field highlights significant progress that has made. it focuses catalyst system transition state key parameters such reactions.

Язык: Английский

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Asymmetric Synthesis of Triphenylmethanes via Organocatalytic Regio- and Enantioselective Friedel–Crafts Alkylation of Aniline Derivatives

Organic Letters, Год журнала: 2023, Номер 25(10), С. 1711 - 1716

Опубликована: Март 9, 2023

Herein, we described a highly regio- and enantioselective Friedel–Crafts alkylation of aniline derivatives with in situ generated ortho-quinone methides enabled by chiral phosphoric acid, furnishing wide range enantioenriched triarylmethanes bearing three similar benzene rings high yields (up to 98%) excellent stereoselectivities 98% ee). Furthermore, the large-scale reactions diversified transformations product demonstrate practicality protocol. Density functional theory calculations elucidate origin enantioselectivity.

Язык: Английский

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Electron-rich benzofulvenes as effective dipolarophiles in copper(i)-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides

Chemical Science, Год журнала: 2023, Номер 14(20), С. 5460 - 5469

Опубликована: Янв. 1, 2023

A series of benzofulvenes without any electron-withdrawing substituents were employed as 2π-type dipolarophiles for the first time to participate in Cu(i)-catalyzed asymmetric 1,3-dipolar cycloaddition (1,3-DC) reactions azomethine ylides. An intrinsic non-benzenoid aromatic characteristic from serves a key driving force activation electron-rich benzofulvenes. Utilizing current methodology, wide range multi-substituted chiral spiro-pyrrolidine derivatives containing two contiguous all-carbon quaternary centers formed good yield with exclusive chemo-/regioselectivity and high excellent stereoselectivity. Computational mechanistic studies elucidate origin stereochemical outcome chemoselectivity, which thermostability these products is major factor.

Язык: Английский

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Enantioselective construction of chiral gem-difluorinated C2-quaternary indoline via dual MgSO₄–CPA-catalyzed asymmetric Mannich reactions

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(5), С. 1430 - 1436

Опубликована: Янв. 1, 2024

Herein, the synthesis of 2-(3,3-difluoro-2-phenylindolin-2-yl)-1-phenylethan-1-one scaffolds through asymmetric Mannich reactions between 3,3-difluoro cyclic ketimines and simple ketones is described.

Язык: Английский

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Asymmetric Organocatalyzed Cyclization Cascade Reactions of 3,3-Difluoro-2-aryl-3H-indoles and Enamides

Organic Letters, Год журнала: 2024, Номер 26(6), С. 1154 - 1159

Опубликована: Фев. 7, 2024

The direct functionalization of β-C(sp2)-H bonds in enamides has garnered increasing attention within the realm organic synthesis. However, these remarkable advancements are predominantly dependent on transition metals; limited success been achieved via organocatalytic catalysis. Herein, we report a CPA-catalyzed cascade intramolecular cyclization to synthesize chiral dihydropyrimido[1,6-a]indoles bearing gem-difluoromethylene. Moreover, this methodology enables synthesis diverse with outstanding enantioselectivities moderate high yields.

Язык: Английский

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Phosphine‐Catalyzed (3 + 2) Annulation of δ‐Hydroxyl Allenylic Alcohols with Pyrazolinone‐Derived Ketimines

ChemistrySelect, Год журнала: 2025, Номер 10(3)

Опубликована: Янв. 1, 2025

Abstract The phosphine‐catalyzed (3 + 2) annulation reaction of δ ‐hydroxyl‐substituted allenylic alcohols with pyrazolinone‐derived ketimines has been developed, giving a variety spiro dihydropyrrole‐dihydropyrazolone derivatives in high yields good diastereoselectivities. Various unsaturated and diverse worked well under mild conditions, 31 examples were provided up to 97% yield >20:1 diastereoselectivity. scale‐up further transformations the product successfully acheived, three derivation experiments showed feasibility product. These results revealed that current could be useful tool for synthesis derivatives. In addition, we also investigated asymmetric version this ketimines, 86% ee chiral was obtained use bifunctional phosphine catalyst.

Язык: Английский

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Enantioselective Synthesis of Chiral 2,2-Difluoro-spiroindanone-dihydroquinazolinones by CPA-Catalyzed Cyclization Reactions

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Янв. 25, 2025

The synthesis of chiral gem-difluorinated spiro-heterocyclic compounds continues to be a significant challenge in organic chemistry due their widespread applications across various fields. Therefore, efficient asymmetric approaches for the spiroindanone-dihydroquinazolinones are particularly valuable, especially industrial manufacturing fluorinated drugs. Herein, we developed CPA-catalyzed enantioselective cyclization reactions gem-difluoroalkyl 1,3-indandiones with anthranilamides achieve 2,2-difluoro-spiroindanone-dihydroquinazolinones good high yields excellent enantioselectivities. Moreover, mechanism experiment proved that gem-difluoro substitution pattern promotes reaction.

Язык: Английский

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