Enantiodivergent Kinetic Resolution of 1,1′‐Biaryl‐2,2′‐Diols and Amino Alcohols by Dipeptide‐Phosphonium Salt Catalysis Inspired by the Atherton–Todd Reaction

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(27), P. 14921 - 14930

Published: March 17, 2021

Abstract A highly enantiodivergent organocatalytic method is disclosed for the synthesis of atropisomeric biaryls via kinetic resolution inspired by a dipeptide‐phosphonium salt‐catalyzed Atherton–Todd (A‐T) reaction. This flexible approach led to both R ‐ and S ‐enantiomers fine‐tuning bifunctional phosphonium with excellent selectivity factors ( s ) up 1057 525, respectively. The potential newly synthesized O‐phosphorylated biaryl diols was illustrated axially chiral organophosphorus compounds. Mechanistic investigations suggest that halide catalyst differentiates between in‐situ‐generated P‐species in A‐T process, mainly involving phosphoryl chloride phosphoric anhydride, thus leading O‐phosphorylation reactions. Furthermore hydrogen bonding interactions catalysts phosphorus molecules were crucial asymmetric induction.

Language: Английский

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Electrophilic Selenium-Catalyzed Desymmetrizing Cyclization to Access P-Stereogenic Heterocycles

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(20), P. 13301 - 13309

Published: Oct. 2, 2023

The construction of phosphorus stereocenters under metal-free conditions remains a formidable challenge. Herein, we report mechanistically distinct chiral electrophilic selenium catalysis-enabled desymmetrizing cyclization to access valuable phosphorus-stereogenic heterocycles with high efficiency. This ambient temperature method affords broad range compounds that bear phenolic hydroxyl group as useful synthetic handle and, thus, enriches the toolbox for rapid generation molecular complexity. control experiments and DFT calculations indicate dual-hydrogen-bonding bridge formed between substrate TfO– anion plays crucial role in determining enantioselectivity transformation.

Language: Английский

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Two-Component Redox Organocatalyst for Peptide Bond Formation

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(8), P. 3637 - 3643

Published: Feb. 21, 2022

Peptides are fundamental therapeutic modalities whose sequence-specific synthesis can be automated. Yet, modern peptide remains atom uneconomical and requires an excess of coupling agents protected amino acids for efficient amide bond formation. We recently described the rational design organocatalyst that operate on Fmoc acids─the standard monomers in automated (J. Am. Chem. Soc. 2019, 141, 15977). The catalytic cycle centered conversion carboxylic acid to selenoester, which was activated by a hydrogen bonding scaffold amine coupling. selenoester generated situ from diselenide catalyst stoichiometric amounts phosphine. Although prior system catalyzed oligopeptide solid phase, it had two significant requirements limited its utility as alternative agents─it depended phosphine required molecular sieves dehydrating agent. Here, we address these limitations with optimized method only no new utilizes two-component organoreductant/organooxidant-recycling strategy catalyze

Language: Английский

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Solvent effect on the ⁷⁷Se NMR chemical shifts of diphenyl diselenides

New Journal of Chemistry, Journal Year: 2024, Volume and Issue: 48(7), P. 2971 - 2978

Published: Jan. 1, 2024

Herein, we evaluated the solvent effect on 77 Se NMR chemical shifts of diphenyl diselenides. To gain a deeper insight into shift behavior, DFT calculations have been performed.

Language: Английский

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Metal‐Free Synthesis of Unsymmetrical Aryl Selenides and Tellurides via Visible Light‐Driven Activation of Arylazo Sulfones

European Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 2020(47), P. 7358 - 7367

Published: Nov. 17, 2020

A protocol for the visible light driven preparation of unsymmetrical (hetero)aryl selenides and tellurides is described herein. The method exploits peculiar photoreactivity arylazo sulfones that act as thermally stable, precursors aryl radicals under both photocatalyst‐ additive‐free conditions. developed shows an impressive versatility (more than fifty compounds isolated).

Language: Английский

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Visible light photocatalytic phosphorylation of heteroatom nucleophiles triggered by phosphorus-centered radical cations

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(11), P. 4528 - 4535

Published: Jan. 1, 2023

A photocatalytic phosphorylation of heteroatom nucleophiles has been achieved via the direct coupling phosphorus-centered radical cations with nucleophiles.

Language: Английский

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Construction of C–P Bonds from Free Cyclobutanone Oximes and Chlorophosphines via Radical–Radical Coupling

Organic Letters, Journal Year: 2024, Volume and Issue: 26(15), P. 3208 - 3212

Published: April 10, 2024

Herein, we report a catalyst-free reaction of cyclobutanone oximes with chlorophosphines (R2PCl), which forms fragile C═N–O–PR2 species that undergoes N–O homolysis, fragmentation, and radical–radical coupling, leading to the formation cyano-containing phosphine oxides in good yields. The features an situ activation for radical generation, R2PCl plays dual role as both activator reactant.

Language: Английский

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Phosphoramidates as promising low-loading flame retardants for low density polyethylene

Polymer Degradation and Stability, Journal Year: 2025, Volume and Issue: unknown, P. 111217 - 111217

Published: Jan. 1, 2025

Language: Английский

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Selenium‐NMR Spectroscopy in Organic Synthesis: From Structural Characterization Toward New Investigations

Asian Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 10(1), P. 91 - 128

Published: Nov. 27, 2020

Abstract This review article deals with organic synthesis from the perspective of selenium‐77 nuclear magnetic resonance (NMR) spectroscopy. Different types reactions are briefly discussed, incorporating mechanism aspects through 77 Se NMR observable intermediates and by‐products. The experiments demonstrated in terms structural characterization new insights for reactions. ability to visualize different molecules a reaction mixture provides facile versatile route development synthetic organoselenium compounds. Thus, describes strategies accomplished mainly past five years syntheses applications compounds, focusing on

Language: Английский

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Primary Amination of Ar₂P(O)–H with (NH₄)₂CO₃ as an Ammonia Source under Simple and Mild Conditions and Its Extension to the Construction of Various P–N or P–O Bonds

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(5), P. 3254 - 3264

Published: Jan. 24, 2022

A facile and efficient method for the synthesis of primary phosphinamides from Ar2P(O)-H reagents with stable readily available ammonium carbonate as an ammonia source is disclosed herein first time. This ethyl bromoacetate-mediated amination proceeds smoothly under mild simple conditions, without any metal catalyst or oxidant. Moreover, this also appropriate reaction a variety amines, alcohols, phenols to construct P-N P-O bonds, features handy operation, good functional group tolerance, broad substrate scope.

Language: Английский

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