Ligand-controlled divergent asymmetric C(sp3)−H and C(sp3)−O insertion via vinyl cations

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: May 2, 2025

The insertion of either C-H bond or C-O via cleavage has proven to be a very attractive strategy for the construction C-C and bonds in organic synthesis. However, such divergent catalytic asymmetric reactions selective formation C(sp3)-H formal C(sp3)-O products from same precursors are rarely explored. Herein, we report ligand-controlled reaction vinyl cations by non-diazo approach, leading practical atom-economical assembly range chiral spiro fused polycyclic pyrroles generally moderate excellent yields with chemo- enantioselectivities. Importantly, this protocol not only represents rare example successful reaction, but also constitutes an enantioselective 1,6-C-H carbenoid into acetals approach.

Language: Английский

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Enantioselective N-Heterocyclic Carbene-Catalyzed Hauser-Kraus Annulations for the Construction of C–N Axially Chiral Phthalimde Derivatives

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(17)

Published: Aug. 19, 2024

The Hauser-Kraus annulation is one of the most powerful methods to construct polycyclic hydroquinone from 3-cyano phthalides and Michael acceptors. Although these have been developed for more than 46 years, asymmetric catalytic version has remained underdeveloped. Inspired by N-heterocyclic carbene (NHC)-catalyzed Stetter reaction via Breslow intermediate, herein, we an NHC-catalyzed enantioselective a phthalide-type intermediate. With help NHC catalyst ynamide coupling reagent, proceeds under mild conditions at room temperature, giving corresponding chiral in moderate good yields, with high enantioselectivities. key intermediate was successfully isolated confirmed. kinetic thermal dynamic features cascade were also explored density functional theory (DFT) calculation. Learning wide application annulation, this method hopeful bring shortcuts facile synthesis sophisticated compounds. Besides, discovery expand synthetic potentials organocatalysis.

Language: Английский

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TFPN-mediated racemization/epimerization-free amide and peptide bond formation

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(19), P. 5422 - 5428

Published: Jan. 1, 2024

A new electron-deficient aromatic-based coupling reagent, tetrafluorophthalonitrile (TFPN), designed according to the concept of dual reagents, is developed facilitate amide and peptide bond formation in a one-pot, two-step manner.

Language: Английский

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Brønsted acid catalyzed Ficini [2 + 2] cycloaddition of ynamides with enones

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(21), P. 4264 - 4268

Published: Jan. 1, 2024

Herein, we describe a novel metal-free Brønsted acid-catalyzed Ficini [2 + 2] cycloaddition of ynamides with enones under mild reaction conditions, leading to the formation various cyclobutenamides in generally good excellent yields within short times. This work represents first example involved nonmetal-catalyzed enones.

Language: Английский

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Copper-catalyzed intermolecular formal [4 + 1] annulation of 1,5-diynes with benzocyclobutenones

Tetrahedron Chem, Journal Year: 2024, Volume and Issue: 12, P. 100090 - 100090

Published: Aug. 14, 2024

Language: Английский

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Chemo-selective modification of cysteine residue: synthesis and application in the discovery of potential drug candidates

Published: Sept. 6, 2024

Chemo-select modification of peptides, targeting a handful the most reactive proteinogenic amino acids (AAs), is gradually utilized to address medical needs peptide drugs and biopharmaceuticals. Cysteine (Cys), one less abundant AAs in many biological proteins, plays vital role catalysis, signal transduction, redox regulation gene expression. In natural (α-AAs) residues, Cys exhibits high nucleophilicity low redox-active potential, making it primary target for site-selective conjugation. This review summarizes several representative Cys-peptide/protein conjugation strategies developed recent years, including polar reactions, radical coupling stapling techniques.

Language: Английский

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Recyclable Pd(OAc)2/2P(3-tol)3/PEG-400 System for Regio- and Stereoselective Addition of Boronic Acids to Ynamides

Synthesis, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 25, 2024

Abstract Pd(OAc)2/2P(3-tol)3 in poly(ethylene glycol) (PEG-400) is shown to be a highly efficient catalyst for the regio- and stereoselective addition of boronic acids ynamides. The reaction proceeds smoothly at 70 °C with Na2CO3 as base, delivering variety (Z)-α,β-disubstituted enamides good excellent yields high stereoselectivity. isolation crude products can facilely performed by extraction diethyl ether more importantly, Pd(OAc)2/2P(3-tol)3/PEG-400 system could readily recycled reused than six times without any significant loss its catalytic efficiency.

Language: Английский

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Catalytic Cycloaddition Reactions of Ynol and Thioynol Ethers

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 25, 2024

Comprehensive Summary Electron‐rich alkynes, such as ynol and thioynol ethers, have proven to be versatile appealing partners in catalytic cycloaddition reactions, thus raised considerable attentions owing the practical application modular assembly of valuable carbo‐ heterocycles. The past decades witnessed inspiring advances this emerging field, an increasing number related discoveries been exploited. Divided into two main sections on basis substrate type, each section comprehensive review will initially summarize their synthetic preparations subsequently examine reactivity every sort with emphasis methodology development, aimed at providing access burgeoning area encouraging further innovations near future. Key Scientists For 2004, Kozmin et al. firstly developed a silver‐catalyzed [2 + 2] siloxy alkynes electron‐poor olefins. In 2012, Hiyama realized palladium‐catalyzed formal [4 annulation alkynyl aryl ethers internal alkynes. same year, Sun discovered efficient [6 cyclization between 2‐(oxetan‐3‐yl)benzaldehydes by applying HNTf 2 catalyst. 2017, Wender first utilized vinylcyclopropanes (VCPs) coupling [5 ethers. 2018 2020, Ye reported zinc‐catalyzed [3 3] cycloaddition, respectively. Hilt employing sulfides acyclic 1,3‐dienes. 2006, ruthenium‐catalyzed bicyclic alkenes was accomplished Tam. 2014, elegant iridium‐catalyzed click reaction thioalkynes azides.

Language: Английский

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Efficient Approach to AviCys Analogues via Regio- and Stereoselective Hydrosulfuration of Ynamides

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

A novel synthetic strategy for the construction of AviCys analogues via a highly efficient regio- and stereoselective hydrosulfuration ynamides was reported.

Language: Английский

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Copper‐Catalyzed Dearomative Cyclization of Indolyl Ynamides for Synthesis of Pentacyclic Spiroindolines

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 23, 2024

Abstract The dearomatization of indoles with ynamides is a convenient access towards polycyclic spiroindolines, which can be initiated by α‐ and β‐additions ynamides. Currently, the related β‐addition dearomative cyclization requires noble‐metal catalyst or stoichiometric oxidant. Herein, we report copper‐catalyzed aryl‐substituted indolyl through regioselective onto ynamides, providing pentacyclic spiroindolines in 81–97% yields >25:1 diastereoselectivities. Moreover, preliminary success has been obtained for catalytic enantioselective cyclization.

Language: Английский

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