Design principles of the use of alkynes in radical cascades

Nature Reviews Chemistry, Journal Year: 2023, Volume and Issue: 7(6), P. 405 - 423

Published: March 28, 2023

Language: Английский

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1,2‐Difunctionalization of Acetylene Enabled by Light

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(16)

Published: Feb. 27, 2023

Although the direct conversion of gaseous acetylene into value-added liquid commodity chemicals is becoming increasingly attractive, majority established methodologies are focused on cross-coupling, hydro-functionalization, and polymerization. Herein, we describe a 1,2-difunctionalization method that inserts directly readily available bifunctional reagents. This provides access to diverse C2-linked 1,2-bis-heteroatom products in high regio- stereoselectivity along with opening up previously unexplored synthetic directions. In addition, demonstrate this method's potential by converting obtained functionalized molecules chiral sulfoxide-containing bidentate ligands. Using combination experimental theoretical methods, mechanism for insertion reaction was investigated.

Language: Английский

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Tetrabutylammonium decatungstate (TBADT), a compelling and trailblazing catalyst for visible-light-induced organic photocatalysis

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(19), P. 3799 - 3842

Published: Jan. 1, 2024

Tetrabutylammonium decatungstate (TBADT) has recently emerged as an intriguing photocatalyst under visible-light or near-visible-light irradiation in a wide range of organic reactions that were previously not conceivable. Given its ability to absorb visible light and excellent effectiveness activating unactivated chemical bonds, it is promising addition traditional photocatalysts. This review covers some the contemporary developments photocatalysis enabled by TBADT catalyst 2023, with contents organized reaction type.

Language: Английский

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Asymmetric imino-acylation of alkenes enabled by HAT-photo/nickel cocatalysis

Chemical Science, Journal Year: 2023, Volume and Issue: 14(23), P. 6449 - 6456

Published: Jan. 1, 2023

By merging nickel-mediated facially selective aza-Heck cyclization and radical acyl C-H activation promoted by tetrabutylammonium decatungstate (TBADT) as a hydrogen atom transfer (HAT) photocatalyst, we accomplish an asymmetric imino-acylation of oxime ester-tethered alkenes with readily available aldehydes the source, enabling synthesis highly enantioenriched pyrrolines bearing acyl-substituted stereogenic center under mild conditions. Preliminary mechanistic studies support Ni(i)/Ni(ii)/Ni(iii) catalytic sequence involving intramolecular migratory insertion tethered olefinic unit into Ni(iii)-N bond enantiodiscriminating step.

Language: Английский

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Nickel/Quinim Enabled Asymmetric Carbamoyl‐Acylation of Unactivated Alkenes

Chinese Journal of Chemistry, Journal Year: 2023, Volume and Issue: 41(14), P. 1673 - 1678

Published: Feb. 14, 2023

Comprehensive Summary Transition metal‐catalyzed difunctionalization of tethered alkene has emerged as a prevailing tool for the expedient construction synthetically valuable cyclic compounds. However, most efforts have been devoted to reaction styrene‐type substrates due their rigid scaffold and high reactivity. With respect nonaromatic olefin, especially mono‐substituted alkene, still remains largely underdeveloped. Herein, we disclose nickel/Quinim complex TBADT‐cocatalyzed asymmetric carbamoyl‐acylation unactivated on carbamoyl chlorides with diverse aldehydes. The exhibits broad substrate scope good functional group tolerance, well efficiency enantioselectivity. Both monosubstituted 1,1‐substituted alkenes can work either aliphatic or aromatic aldehydes under current protocol, providing convenient access an array medicinally useful chiral γ‐lactams derivatives bearing convertible acyl functionality. This showcases more application possibilities Quinim ligand in future catalytic transformations.

Language: Английский

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Visible-light-induced [3+2] cycloadditions of donor/donor diazo intermediates with alkenes to achieve (spiro)-pyrazolines and pyrazoles

Chemical Science, Journal Year: 2023, Volume and Issue: 14(38), P. 10411 - 10419

Published: Jan. 1, 2023

To date, [3 + 2] cycloadditions of diazo esters with alkynes or alkenes have been a robust tool to generate pyrazoles and pyrazolines. However, methods capable generating donor/donor species from readily available N-tosylhydrazones furnish cycloadditions, remain elusive. Herein, we describe the first visible-light-induced precursors afford novel (spiro)pyrazolines bearing quaternary center. This protocol shows tolerable substrate scope covering versatile carbonyl compounds alkenes. Late-stage functionalization bioactive molecules, one-pot approach, gram-scale synthesis also introduced successfully prove practicability. At last, mechanistic experiments DFT studies suggested formation non-covalent interactions enabling activation intermediates.

Language: Английский

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Recent advances in hydrogen atom transfer induced C(sp³)–H functionalizations initiated by radical addition to alkynes

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 11(4), P. 1232 - 1250

Published: Dec. 28, 2023

Recent advances in HAT-induced C(sp 3 )–H functionalizations triggered by radical addition to alkynes, including 5- exo-trig , endo-trig 4- and 6- cyclization cascades, intermolecular functionalizations, are summarized.

Language: Английский

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Visible-light-induced reusable decatungstate-photocatalyzed radical cascade alkylation/cyclization of isocyanides with simple alkanes, ethers and ketones

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

Published: Jan. 1, 2024

With reusable sodium decatungstate (NaDT) as the photocatalyst, hydrocarbons (alkanes, ethers and ketones) alkylating agents, a wide range of alkylated fused N-heterocycles were obtained in high yield.

Language: Английский

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A TBADT photocatalyst-enabled radical-induced cyclization pathway to access functionalized dihydrobenzofurans

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(59), P. 9094 - 9097

Published: Jan. 1, 2023

Herein, this work describes a photoinduced visible light-mediated radical cyclization for constructing dihydrobenzofuran (DHB) scaffolds. Notably, cascade photochemical process is tolerable with various aromatic aldehydes and diverse alkynyl aryl ethers proceeds via an intramolecular 1,5-hydrogen atom transfer (HAT) pathway. Significantly, acyl C-H activation under mild conditions has been achieved without the use of additives or reagents. The photocatalyst, tetrabutylammonium decatungstate (TBADT), plays important role in present strategy by facilitating well-known hydrogen during course reaction.

Language: Английский

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Controllable Synthesis of Cyclopenta[b]indolines via Photocatalytic Fluoroalkylative Radical Cyclization Cascade of Ynamides

Organic Letters, Journal Year: 2024, Volume and Issue: 26(22), P. 4643 - 4647

Published: May 29, 2024

A de novo method for direct construction of cyclopenta[b]indolines via a photocatalytic fluoroalkylative radical cyclization cascade ynamides has been established, which proceeds sequence addition, 1,5-HAT, 5-endo-trig cyclization, intramolecular arylation, and oxidative deprotonation. This protocol allows the controllable assembly tricyclic architecture with three contiguous stereocenters, showcasing its high efficiency, compatibility, regio- diastereoselectivity accessing pharmacologically significant fluoroalkylated cyclopenta[b]indolines. It represents one very few examples tetrafunctionalization alkynes.

Language: Английский

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