Cooperative Photoredox and Cobalt‐Catalyzed Acceptorless Dehydrogenative Functionalization of Cyclopropylamides towards Allylic N,O‐Acyl‐acetal Derivatives

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(24)

Published: April 13, 2024

Abstract We disclose herein a novel photoredox and cobalt co‐catalyzed ring‐opening/acceptorless dehydrogenative functionalization of mono‐donor cyclopropanes. This sustainable atom‐economic approach allows the rapid assembly wide range allylic N,O ‐acyl‐acetal derivatives. The starting materials are readily available reaction features mild conditions, broad substrate scope, excellent functional group compatibility. optimized conditions accommodate assorted cycloalkylamides primary, secondary, tertiary alcohols, with applications in late‐stage pharmaceutically relevant compounds, stimulating further utility medicinal chemistry. Moreover, selective nucleophilic substitutions various carbon nucleophiles were achieved one‐pot fashion, offering reliable avenue to access some cyclic acyclic

Language: Английский

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Intramolecular chaperone-assisted dual-anchoring activation (ICDA): a suitable preorganization for electrophilic halocyclization

Chemical Science, Journal Year: 2024, Volume and Issue: 15(16), P. 6130 - 6140

Published: Jan. 1, 2024

The halocyclization reaction represents one of the most common methodologies for synthesis heterocyclic molecules. Many efforts have been made to balance relationship between structure, reactivity and selectivity, including design new electrophilic halogenation reagents utilization activating strategies. However, discovering universal or strategies remains challenging due case-by-case practice different substrates cyclization models. Here we report an intramolecular chaperone-assisted dual-anchoring activation (ICDA) model halocyclization, taking advantage non-covalent orientation as driving force. This protocol allows a practical, catalyst-free rapid approach access seven types small-sized, medium-sized, large-sized units realize polyene-like domino halocyclizations, exemplified by nearly 90 examples, risk-reducing flow gram-scale synthesis. DFT studies verify crucial role ICDA in affording suitable preorganization transition state stabilization X

Language: Английский

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Recent Advances in Catalytic Asymmetric Syntheses of Functionalized Heterocycles via Halogenation/Chalcogenation of Carbon‐Carbon Unsaturated Bonds

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(23), P. 3974 - 4005

Published: Oct. 20, 2022

Abstract Halogen (fluorine, chlorine, bromine, iodine) or chalcogen (sulfur, selenium)‐containing heterocycles are widely recognized as key building blocks in many natural products and bioactive targets. Catalytic asymmetric halogenation/chalcogenation of carbon‐carbon unsaturated bonds via onium ion transformations efficient methods to obtain diverse chiral heterocyclic backbones. In the past few years, catalytic enantioselective versions halo/thio/seleno‐functionalizations with various halogen electrophiles have experienced constant development. This review highlights those advances preparing functionalized promoted by organocatalysts metal‐based catalysts. magnified image

Language: Английский

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Phosphonium-Catalyzed Monoreduction of Bisphosphine Dioxides: Origin of Selectivity and Synthetic Applications

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(13), P. 9335 - 9346

Published: March 19, 2024

Controlling product selectivity in successive reactions of the same type is challenging owing to comparable thermodynamic and kinetic properties involved. Here, synergistic interaction two phosphoryl groups bisphosphine dioxides (BPDOs) with a bromo-phosphonium cation was studied experimentally provide practical tool for substrate–catalyst recognition. As eventual result, we have developed phosphonium-catalyzed monoreduction chiral BPDOs access an array synthetically useful monoxides (BPMOs) axial, spiro, planar chirality, which are otherwise synthesize before. The reaction features excellent impressive reactivity. It proceeds under mild conditions, avoiding use superstoichiometric amounts additives metal catalysts simplify synthetic procedure. accessibility scalability allowed rapid construction ligand library optimization asymmetric Heck-type cyclization, laying foundation broad range applications BPMOs catalysis.

Language: Английский

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Chemodivergent Parallel Kinetic Resolution of Paracyclophanes: Enantiomer Fishing with Different Substrates

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(46)

Published: July 25, 2024

Abstract An unprecedented chemodivergent strategy for parallel kinetic resolution (PKR) is disclosed through which two planar chiral products bearing different structures were simultaneously afforded with opposite stereoselectivities. Two achiral esters are activated by one single N‐heterocyclic carbene (NHC) catalyst to react the enantiomers of racemic imine substrate in a fashion. distinct and stereoselectivities respectively from same reaction system good excellent yields, enantio‐ diastereoselectivities. Control experiments studies carried out probe dynamic properties during progress. The pyridine lactam show interesting applications both asymmetric synthesis pesticide development.

Language: Английский

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Functionalized Terthiophene as an Ambipolar Redox System: Structure, Spectroscopy, and Switchable Proton-Coupled Electron Transfer

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 27, 2025

Organic redox systems that can undergo oxidative and reductive (ambipolar) electron transfer are elusive yet attractive for applications across synthetic chemistry energy science. Specifically, the use of ambipolar in proton-coupled (PCET) reactions is largely unexplored but could enable "switchable" reactivity wherein uptake release hydrogen atoms controlled using a stimulus. Here, we describe synthesis characterization an functionalized terthiophene (TTH) bearing methyl thioether phosphine oxide groups exhibits switchable PCET reactivity. Electrochemical studies established TTH be reversibly oxidized reduced, prompting cationic anionic radicals on single platform. Combined structural, spectroscopic, computational investigations revealed influence moieties electronic structure results stabilization both radicals. Upon single-electron oxidation, serves as atom acceptor undergoes with 1,4-dihydroquinone to generate hydroxyphosphonium species. The process was found reversible upon reduction, acting donor reaction 2,3-dimethylanthraquinone. thermochemistry O–H bond formed cleaved during sequence investigated, revealing weakening 30 kcal/mol underpins Overall, these provide electrochemical, thermochemical foundation ambipolarity control organic systems.

Language: Английский

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Parallel kinetic resolution of aziridines via chiral phosphoric acid-catalyzed apparent hydrolytic ring-opening

Chemical Science, Journal Year: 2023, Volume and Issue: 14(43), P. 12152 - 12159

Published: Jan. 1, 2023

An intriguing chiral phosphoric acid-catalyzed asymmetric hydrolytic ring-opening of racemic aziridines via regiodivergent PKR is presented, providing an efficient approach for the construction β-amino alcohols.

Language: Английский

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Parallel Kinetic Resolution through Palladium-Catalyzed Enantioselective Cycloimidoylation: En Route to Divergent N-Heterocycles Bearing a Quaternary Stereogenic Center

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(24), P. 14918 - 14925

Published: Nov. 23, 2022

An example of a parallel kinetic resolution catalyzed by palladium to produce enantioenriched five- and six-membered N-heterocycles in one pot was developed. Dihydroisoquinolines 1H-isoindoles containing quaternary stereogenic center were obtained from racemic isocyanides high yields with good enantioselectivities under mild conditions. A 6,6′-dipropyl substituted SPINOL-derived phosphoramidite used as the chiral ligand for catalyst, resulting regiodivergent stereospecific cycloimidoylation. Density functional theory (DFT) calculations reveal origin regio- enantioselectivity during C(sp2)–H imidoylative cyclization process.

Language: Английский

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Stereogenic-at-Cobalt(III) Complex Catalyzed Halocyclization of Alkynes: Enantioselective Access to Axially Chiralortho-Halo-C2-indoles

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(9), P. 6146 - 6158

Published: April 6, 2023

Here, we report an anionic stereogenic-at-cobalt(III) complex catalysis strategy for the enantioselective halocyclization of ortho-alkynylanilines using N-halosuccinimide (NXS) as halogen source. This protocol provides a distinct atroposelective approach to access axially chiral ortho-halo-C2-indole skeletons in excellent yields with good high enantioselectivities (up 99% yield, 99:1 er).

Language: Английский

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Asymmetric Synthesis of Halocyclized Products by Using Various Catalysts: A State‐of‐the‐Art Review

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(32)

Published: July 25, 2022

Abstract Halogens play a crucial part in synthetic organic chemistry. Halo‐cyclized products hold numerous applications the pharmaceutical industries, agrochemicals, natural product synthesis, and material Thus, this review will discuss role of various catalysts, such as from metal‐catalysts to organocatalysts, under different conditions synthesize halocyclized products. The synthesis catalytic mechanisms underlying asymmetric transformations also be covered by emphasizing enantioselectivities, diastereoselectivities, regioselectivities existing pieces literature.

Language: Английский

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