Atropisomers beyond the C–C axial chirality: Advances in catalytic asymmetric synthesis

Chem, Journal Year: 2022, Volume and Issue: 8(7), P. 1855 - 1893

Published: May 6, 2022

Language: Английский

---

Carbene‐Catalyzed Asymmetric Construction of Atropisomers

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(50), P. 26026 - 26037

Published: July 16, 2021

Atropisomeric molecules have found proven applications and shown promising potential in chemistry medicine. The design of N-heterocyclic carbene (NHC) catalyzed reactions to construct atropisomerically enriched has emerged as an important research topic recent years. These include kinetic resolutions, asymmetric desymmetrizations, central-to-axial chirality conversions, cycloadditions. This Minireview evaluates summarizes the progress NHC-based organic catalysis for access atropisomers, briefly states our personal perspectives on future advancement this topic. NHC provided rich unique reaction modes that led success synthesis central-chiral molecules. It is expected similar could also be achieved developing prepare atropisomeric molecules, including those not easily accessible by other methods.

Language: Английский

---

Stereoselective construction of atropisomers featuring a C–N chiral axis

Green Synthesis and Catalysis, Journal Year: 2022, Volume and Issue: 3(2), P. 117 - 136

Published: Jan. 4, 2022

Atropisomeric C–N compounds belong to an important class of axially chiral compounds. However, whereas the asymmetric synthesis biaryl atropisomers have been well established, general and efficient strategies access single enantiomers are still rare. Until recently, innovative methods developed, providing new opportunities for highly stereoselective this vital atropisomers. Herein, we comprehensively summarize development in emerging field give some insights into future advance. Emphasis is placed on synthetic strategies.

Language: Английский

---

Asymmetric Synthesis of Axially Chiral C−N Atropisomers

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 28(28)

Published: Feb. 22, 2022

Molecules with restricted rotation around a single bond or atropisomers are found in wide number of natural products and bioactive molecules as well chiral ligands for asymmetric catalysis smart materials. Although most these compounds biaryls heterobiaryls displaying C-C stereogenic axis, there is growing interest less common more challenging axially C-N atropisomers. This review offers an overview the various methodologies available their synthesis. A brief introduction initially given to contextualize skeletons, including historical background examples containing axes. The preparation different families based then presented from anilides five- six-membered ring heterocycles. Special emphasis has been modern catalytic strategies over past decade synthesis scaffolds. Applications methods biologically active will be highlighted along text.

Language: Английский

---

Recent Progress toward the Construction of Axially Chiral Molecules Catalyzed by an N-heterocyclic Carbene

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(20), P. 12520 - 12531

Published: Sept. 28, 2021

Axial chirality widely exists in natural products, pharmaceutical compounds, and other functional molecules; these axially chiral compounds also find wide utility as catalysts or ligands organic synthetic chemistry. Nevertheless, whereas significant progress has been made toward the synthesis of enantioenriched molecules over past two decades, strategies involving organocatalysis have only started to emerge recently. N-heterocyclic carbene (NHC) organocatalysts recognized be powerful tools for rapid construction complex molecular architectures. However, previous works mainly focused on assembly point recently it realized that asymmetric axial could achieved by using NHCs organocatalysts. This Perspective highlights developments advances scaffolds catalyzed NHCs. The aim this is provide an overview area serve a stepping stone future investigations.

Language: Английский

---

Carbene-catalyzed atroposelective synthesis of axially chiral styrenes

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Jan. 10, 2022

Abstract Axially chiral styrenes bearing a axis between sterically non-congested acyclic alkene and an aryl ring are difficult to prepare due low rotational barrier of the axis. Disclosed here is N -heterocyclic carbene (NHC) catalytic asymmetric solution this problem. Our reaction involves ynals, sulfinic acids, phenols as substrates with NHC catalyst. Key steps involve selective 1,4-addition anion acetylenic acylazolium intermediate sequential E -selective protonation set up affords axially product > 99:1 e.r ., 20:1 / Z selectivity, excellent yields. The sulfone carboxylic ester moieties in our styrene products common bioactive molecules catalysis.

Language: Английский

---

Enantioselective Access to Triaryl-2-pyrones with Monoaxial or Contiguous C–C Diaxes via Oxidative NHC Catalysis

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(4), P. 2565 - 2575

Published: Feb. 6, 2023

We present herein an unprecedented stereoselective synthesis of triaryl-2-pyrones with monoaxial or contiguous diaxes from readily available starting materials. This N-heterocyclic carbene catalysis method adopts atroposelective annulation 2-aryketones ynals under oxidative conditions. The includes the construction one two axes in a single operation, achieves step economy, and affords axially chiral moderate to good yields, high excellent enantioselectivities. DFT calculations relative energies stereoisomers rotational barriers were performed.

Language: Английский

---

Synthesis of Axially Chiral Aldehydes by N‐Heterocyclic‐Carbene‐Catalyzed Desymmetrization Followed by Kinetic Resolution

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(14)

Published: Jan. 31, 2022

Axially chiral aldehydes have received increasing attention in enantioselective catalysis. However, only very few catalytic methods been developed to construct structurally diverse axially aldehydes. We herein describe an NHC-catalyzed atroposelective esterification of biaryl dialdehydes as a general and practical strategy for the construction Mechanistic studies indicate that coupling proceeds through novel combination desymmetrization kinetic resolution. This protocol features excellent enantioselectivity, mild conditions, good functional-group tolerance, applicability late-stage functionalization provides modular platform synthesis their derivatives.

Language: Английский

---

Generation of azolium dienolates as versatile nucleophilic synthonsvia N-heterocyclic carbene catalysis

Organic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 8(21), P. 6138 - 6166

Published: Jan. 1, 2021

The recent advances in N -heterocyclic carbene (NHC)-catalyzed generation of azolium dienolates from different precursors and their synthetic applications for the construction various valuable molecules are summarized comprehensively this review.

Language: Английский

---

Atroposelective Synthesis of Triaryl α‐Pyranones with 1,2‐Diaxes by N‐Heterocyclic Carbene Organocatalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(52)

Published: Oct. 31, 2022

Atropisomers bearing multiple stereogenic axes are of increasing importance to the field material science, pharmaceuticals, and catalysis. However, atroposelective construction multi-axis atropisomers remains rare challenging, due intrinsical difficulties in stereo-control axes. Herein, we demonstrate a single-step new class 1,2-diaxially chiral triaryl α-pyranones by an N-heterocyclic carbene organocatalytic asymmetric [3+3] annulation well-designed alkynyl acylazolium precursors enolizable sterically hindered 2-aryl ketones. The protocol features broad substrate scope (>50 examples), excellent (most cases >20 : 1 dr, up 99.5 0.5 er), potentially useful synthetic applications. success this reaction relies on rational design structurally matched partners careful selection catalytic system. DFT calculations have also been performed discover rationalize origin high stereoselectivity reaction.

Language: Английский

---