Recent Progress in Chiral Quaternary Ammonium Salt-Promoted Asymmetric Nucleophilic Additions

ACS Catalysis, Journal Year: 2025, Volume and Issue: 15(3), P. 1973 - 2001

Published: Jan. 20, 2025

Chiral quaternary ammonium ion-pair organocatalysis has been widely used in the facile synthesis of chiral molecules with challenging stereocenters. Especially, numerous asymmetric nucleophilic addition reactions have facilitated this strategy. This review systematically summarizes additions promoted by salts past decade. The content is organized according to types electrophiles involved these catalytic transformations. Our own perspectives on future development within highly active research field are also provided.

Language: Английский

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Organocatalytic Atroposelective Fluorooxindole Addition to Coumarin Michael Acceptors

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Organocatalytic atropisomeric synthesis with fluorinated oxindoles and 4-halo-3-nitrocoumarins gives congested structures displaying a Csp2-Csp3 chirality axis an adjacent tetrasubstituted stereogenic carbon center good yields, up to 97% ee 41 : 1 dr. The scalable dehalogenative C-C bond formation is achieved under mild conditions commercially available urea catalyst.

Language: Английский

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Catalytic Asymmetric Mannich-Type Reaction of α-Haloacetonitriles

Organic Letters, Journal Year: 2024, Volume and Issue: 26(36), P. 7546 - 7550

Published: Sept. 4, 2024

An asymmetric Mannich-type addition of aldimines and haloacetonitriles is reported here, yielding halogenated aminonitriles with excellent stereoselectivity, facilitated by a pincer Ni(II) complex as catalyst. Haloacetonitriles are recognized reactive electrophiles, the possibility their use pronucleophile has been almost neglected for many years. The resulting adduct can be readily converted into various valuable derivatives, including chiral aziridines, starting from chlorinated compounds.

Language: Английский

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Base‐Promoted Diastereoselective Addition of 2‐Aryloxy‐2‐Fluoroketones to N‐(tert‐Butylsulfinyl)Imines

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(46)

Published: Dec. 1, 2024

Abstract The asymmetric construction of a quaternary fluorine‐containing stereogenic carboncenter is highly valuable for the development fluoroine‐containing bioactive molecules. Herein, base‐promoted, diastereoselective Mannich‐type reaction 2‐aryloxy‐2‐fluoroketones with N ‐( tert ‐butylsulfinyl)imines has been developed. A number addition products featuring fluorinated stereocarbon centre and β‐fluoroamine structural motif have readily obtained in good yields moderate to diastereoselectivities. absolute configuration major diasteromer was determined by X‐ray crystallography analysis, closed transition‐state mode proposed explain stereochemical outcome this reaction. In addition, product efficiently converted into α‑fluoro‐β‐amino alcohol through desulfinylation followed reduction carbonyl group.

Language: Английский

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