Facile access to benzofuran-fused tetrahydropyridines <i>via</i> catalytic asymmetric [4 + 2] cycloaddition of aurone-derived 1-azadienes with 3-vinylindoles

Koay, Wai Lean; Mei, Guang‐Jian; Lü, Yixin

doi:10.1039/d0qo01236j

Cited by 32 publications

(13 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[47] By using 10 mol% of TRIP catalyst (S-Cat. 8), an array of enecarbamates (57) with substitutions in para-, meta-and ortho-position of the aryl group of the olefin were included in this annulation reaction and the corresponding 2,3,4-trisubstituted chroman products (58) were obtained in high yields with high enantioselectivities and diastereoselectivities (Scheme 17). In addition, a range of o-hydroxybenzyl alcohols (56) with variations of both the quinone methide fragment and the β-aryl substituent could be used in this reaction to generate chroman products bearing three stereogenic centers and could therefore be used in natural product synthesis.…”

Section: Stereoselective [4 + 2] Cycloaddition and Annulation Reactionsmentioning

confidence: 99%

Asymmetric Cycloaddition/Annulation Reactions by Chiral Phosphoric Acid Catalysis: Recent Advances

2022

View full text Add to dashboard Cite

Asymmetric cycloaddition/annulation reactions have contributed greatly to the synthesis of a variety of novel cyclic compounds used in organic synthesis, natural product synthesis, material science, and chemical biology. Thus, chiral phosphoric acid‐catalyzed asymmetric cycloaddition reactions have received the attention of the synthetic community to design new vital asymmetric reactions and synthesize complex molecules for the past two decades. Although several review articles on organocatalyzed asymmetric cycloaddition reactions can be found in the literature, there has been no specific review on CPA‐catalyzed asymmetric cycloaddition/annulation reactions. Herein, the most recent research progress on chiral phosphoric acid catalyzed asymmetric [3+2], [4+2], [2+2], [3+3], [4+3], [4+1] annulation, and 1,3‐dipolar cycloadditions have been compiled and analyzed to demonstrate the importance of chiral phosphoric acid catalysis in asymmetric cycloaddition or annulation reactions.

show abstract

Section: Stereoselective [4 + 2] Cycloaddition and Annulation Reactionsmentioning

confidence: 99%

Asymmetric Cycloaddition/Annulation Reactions by Chiral Phosphoric Acid Catalysis: Recent Advances

2022

View full text Add to dashboard Cite

show abstract

“…In general, binaphthyl is used to synthesize chiral phosphoric acid derivatives. These catalysts have been involved in several reactions including the Diels-Alder, Nazarov, Mukaiyama Aldol, Mannich, Henry, Morita-Baylis-Hillman reactions, and 1,3-dipolar cycloadditions [146][147][148][149][150][151][152][153][154].…”

Section: Phosphoric Acidmentioning

confidence: 99%

Regiodivergent Organocatalytic Reactions

et al. 2021

View full text Add to dashboard Cite

Organocatalysts are abundantly used for various transformations, particularly to obtain highly enantio- and diastereomeric pure products by controlling the stereochemistry. These applications of organocatalysts have been the topic of several reviews. Organocatalysts have emerged as one of the very essential areas of research due to their mild reaction conditions, cost-effective nature, non-toxicity, and environmentally benign approach that obviates the need for transition metal catalysts and other toxic reagents. Various types of organocatalysts including amine catalysts, Brønsted acids, and Lewis bases such as N-heterocyclic carbene (NHC) catalysts, cinchona alkaloids, 4-dimethylaminopyridine (DMAP), and hydrogen bond-donating catalysts, have gained renewed interest because of their regioselectivity. In this review, we present recent advances in regiodivergent reactions that are governed by organocatalysts. Additionally, we briefly discuss the reaction pathways of achieving regiodivergent products by changes in conditions such as solvents, additives, or the temperature.

show abstract

“…To address the above challenges and based on our long-lasting efforts on chiral indole chemistry, we designed a chiral phosphoric acid (CPA)-catalyzed asymmetric dearomative (2+3) cycloaddition of 3-alkyl-2-vinylindoles with azoalkenes for the construction of enantioenriched pyrroloindoline skeletons (Scheme ). In this reaction, azoalkenes attracted our attention because of their high reactivity acting as 1,3-dipole surrogates in the presence of CPA. , Recently, Lu’s group devised elegant approaches on CPA-catalyzed asymmetric (3+2) cycloadditions of azoalkenes with C3-substituted indoles or 3-vinylindoles (Scheme a). In the reaction involving C3-substituted indoles (eq 3), a dearomatization of the indole ring occurred.…”

Section: Introductionmentioning

confidence: 99%

Application of 3-Alkyl-2-vinylindoles in Catalytic Asymmetric Dearomative (2+3) Cycloadditions

et al. 2021

View full text Add to dashboard Cite

The first application of 3-alkyl-2-vinylindoles in catalytic asymmetric dearomative cycloadditions was established by chiral phosphoric acid (CPA)-catalyzed (2+3) cycloaddition with azoalkenes, leading to the generation of chiral pyrroloindolines bearing two tetrasubstituted stereogenic centers in good yields (61–96%) and excellent stereoselectivities (all >95:5 dr, 86–99% ee). This reaction has realized the first enantioselective dearomative cycloaddition of 3-alkyl-2-vinylindoles, which brings a new reactivity to this class of vinylindoles and will enrich the chemistry of 3-alkyl-2-vinylindoles. In addition, this approach has provided a useful strategy for the construction of enantioenriched pyrroloindoline skeletons bearing two tetrasubstituted stereogenic centers. More importantly, the bioassay of these chiral pyrroloindolines has revealed that some compounds exhibit strong anti-cancer activity against Hela and MCF-7 cell lines, which will be helpful for discovering anti-cancer drug candidates.

show abstract

Facile access to benzofuran-fused tetrahydropyridines via catalytic asymmetric [4 + 2] cycloaddition of aurone-derived 1-azadienes with 3-vinylindoles

Abstract: A highly enantioselective [4 + 2] cycloaddition reaction of 1-azadienes with 3-vinylindoles, catalyzed by chiral phosphoric acid has been developed to furnish a range of benzofuran-fused tetrahydropyridines with three contiguous stereogenic centers.

Cited by 32 publications

References 65 publications

Asymmetric Cycloaddition/Annulation Reactions by Chiral Phosphoric Acid Catalysis: Recent Advances

Asymmetric Cycloaddition/Annulation Reactions by Chiral Phosphoric Acid Catalysis: Recent Advances

Regiodivergent Organocatalytic Reactions

Application of 3-Alkyl-2-vinylindoles in Catalytic Asymmetric Dearomative (2+3) Cycloadditions

Contact Info

Product

Resources

About