Recent Advances in Catalytic Asymmetric Construction of Atropisomers

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(8), P. 4805 - 4902

Published: March 27, 2021

Atropisomerism is a stereochemical behavior portrayed by three-dimensional molecules that bear rotationally restricted σ bond. Akin to the well-represented point-chiral molecules, atropisomerically chiral compounds are finding increasing utilities in many disciplines where molecular asymmetry influential. This provides steady demand on atroposelective synthesis, numerous synthetic pursuits have been rewarded with conceptually novel and streamlined methods while expanding structural diversity of atropisomers. review summarizes key achievements stereoselective preparation biaryl, heterobiaryl, nonbiaryl atropisomers documented between 2015 2020. Emphasis placed strategies for each class, examples cited illustrate potential applications accessed atropochiral targets.

Language: Английский

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The Catalytic Formation of Atropisomers and Stereocenters via Asymmetric Suzuki–Miyaura Couplings

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(9), P. 4918 - 4937

Published: April 12, 2022

Although Suzuki–Miyaura cross-coupling is one of the most convenient and well-developed reactions, its applications to asymmetric version deliver highly functionalized atropisomers or nonracemic coupling products have been less explored. Besides some excellent work reported intermittently, reaction remains a significant challenge, particularly for preparing heterocyclic atropisomers. A concise but critical knowledge on this topic may further inspire researchers across various subdisciplines develop innovative practical solutions tackle problem. Therefore, Review aims summarize pioneering cross-couplings cover implementations via homogeneous heterogeneous catalysis during recent years. Most notably, use transition metals other than palladium also described.

Language: Английский

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Enantioselective Cross-Coupling for Axially Chiral Tetra-ortho-Substituted Biaryls and Asymmetric Synthesis of Gossypol

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(17), P. 8036 - 8043

Published: April 2, 2020

The axially chiral tetra-ortho-substituted biaryl skeleton exists in numerous biologically important natural products, pharmaceutical molecules, catalysts, and ligands. efficient synthesis of structures remains a challenging but unsolved problem. Among various asymmetric synthetic protocols, enantioselective Suzuki-Miyaura cross-coupling represents one the most straightforward versatile approaches. Herein we describe powerful coupling enabled by P-chiral monophosphorus ligand BaryPhos, providing broad range synthetically biaryls excellent enantioselectivities yields. In addition to enhanced reactivity for sterically hindered cross-coupling, rational design BaryPhos also new catalysis mode involving noncovalent interactions between two partners effect stereoinduction. This protocol is robust practical, allowing concise therapeutically valuable male contraceptive antitumor agent gossypol.

Language: Английский

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Rhodium(III)‐Catalyzed Atroposelective Synthesis of Biaryls by C−H Activation and Intermolecular Coupling with Sterically Hindered Alkynes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(32), P. 13288 - 13294

Published: April 16, 2020

Abstract Reported herein is the atroposelective synthesis of biaryl NH isoquinolones by Rh III ‐catalyzed C−H activation benzamides and intermolecular [4+2] annulation for a broad scope 2‐substituted 1‐alkynylnaphthalenes, as well sterically hindered, symmetric diarylacetylenes. The axial chirality constructed based on dynamic kinetic transformation alkyne in redox‐neutral with benzamides, insertion being stereodetermining. reaction accommodates both heteroaryl carboxamides proceeds excellent regioselectivity (if applicable) enantioselectivities (average 91.8 % ee ). An enantiomerically diastereomerically pure rhodacyclic complex was prepared offers insight into enantiomeric control coupling system, wherein steric interactions between amide directing group substrate dictate regio‐ enantioselectivity.

Language: Английский

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Synthesis of Axially Chiral 2,2′-Bisphosphobiarenes via a Nickel-Catalyzed Asymmetric Ullmann Coupling: General Access to Privileged Chiral Ligands without Optical Resolution

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(3), P. 1328 - 1333

Published: Jan. 13, 2021

We report an asymmetric homocoupling of ortho-(iodo)arylphosphine oxides and ortho-(iodo)arylphosphonates resulting in highly enantioenriched axially chiral bisphosphine bisphosphonates. These products are readily converted to biaryl bisphosphines without need for auxiliaries or optical resolution. This provides a practical route the development previously uninvestigated atroposelective ligands. The conditions have also proven effective dimerization other, non-phosphorus-containing aryl halides.

Language: Английский

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Construction of Axially Chiral Arylborons via Atroposelective Miyaura Borylation

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(27), P. 10048 - 10053

Published: June 28, 2021

Compared with the well-developed centrally chiral boron chemistry, C–B axially chemistry remains elusive and challenging. Herein we report first atroposelective Miyaura borylation of bromoarenes unsymmetrical diboron reagents for direct catalytic synthesis optically active atropisomeric arylborons. This reaction features broad substrate scope produces arylborons high yields good enantioselectivities.

Language: Английский

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Enantioselective and Diastereoselective C–H Alkylation of Benzamides: Synergized Axial and Central Chirality via a Single Stereodetermining Step

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(15), P. 9151 - 9158

Published: July 9, 2021

In this report, distally disposed axial and central chirality has been installed in a synergistic fashion via rhodium-catalyzed C–H alkylation of benzamides using N-arylmaleimide as the alkylating reagent, which enantio- diastereo-determining steps are merged into single one. The coupling system features mild reaction conditions, broad substrate scope, excellent diastereoselectivity. chiral induction enabled by judicious choice rhodium cyclopentadienyl catalyst that serves to control both orientation olefin unit prochiral C–N bond.

Language: Английский

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XPS and structural studies of Fe3O4-PTMS-NAS@Cu as a novel magnetic natural asphalt base network and recoverable nanocatalyst for the synthesis of biaryl compounds

Scientific Reports, Journal Year: 2021, Volume and Issue: 11(1)

Published: Dec. 30, 2021

Abstract In this research, natural asphalt as a mineral carbonuous material was converted to sodium sulfonate (Na-NAS) and, then, linked Fe 3 O 4 MNPs in order synthesize the magnetic nanocatalyst. Afterwards, Cupper (I) and Cu (II) grafted on -PTMS-NAS. Moreover, it is worth mentioning that synthesized novel nanocatalyst (Fe -PTMS-NAS@Cu) successfully used Suzuki Stille coupling reactions. The -PTMS-NAS@Cu were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission (TEM), energy-dispersive X-ray (EDX), diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), inductively coupled plasma (ICP), BET photoelectron (XPS) analysis. Besides, sulfonation of asphalt, magnetization catalyst, grafting NAS catalyst formation investigated proved carefully. This can be comfortably separated from reaction medium through an external field also recovered reused, while maintaining its catalytic activity.

Language: Английский

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Recent advances in the catalytic asymmetric construction of atropisomers by central-to-axial chirality transfer

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(8), P. 2280 - 2292

Published: Jan. 1, 2022

We highlighted the recent advances in field of central-to-axial chirality transfer for synthesis axially chiral molecules.

Language: Английский

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Atropisomeric Phosphine Ligands Bearing C–N Axial Chirality: Applications in Enantioselective Suzuki–Miyaura Cross-Coupling Towards the Assembly of Tetra-ortho-Substituted Biaryls

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(32), P. 14864 - 14873

Published: Aug. 3, 2022

Biaryl phosphines bearing C(Ar)–C(Ar) axial chirality are commonly known and have been successfully applied in many asymmetric catalyses. Nevertheless, the development of a chiral ligand having an axially C(Ar)–N backbone remains elusive due to its undesirable less restricted rotational barrier. In fact, it is highly attractive overcome this challenge as incorporation N-donor component at axis more favorable toward transient metal coordination, thus, better outcome stereocommunication anticipated approaching substrates. Herein, we present rational design new collection featuring C–N their applications enantioselective Suzuki–Miyaura cross-coupling for accessing steric hindered tetra-ortho-substituted biaryls (26 examples up 98:2 er). It worth noting that embodied carbazolyl framework crucial succeed reaction, by fruitful relief bulky substrate coordination transmetalation via fleeting Pd–N jumping Pd-π fashion. DFT calculation reveals interesting Pd-arene-walking characteristic across plane attaining lower energy-preferred route catalytic cycle. The theoretical study predicts stereooutcome matches enantioselectivity with experimental results.

Language: Английский

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