Hydroamination, Aminoboration, and Carboamination with Electrophilic Amination Reagents: Umpolung-Enabled Regio- and Stereoselective Synthesis of N-Containing Molecules from Alkenes and Alkynes

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(2), P. 648 - 661

Published: Jan. 6, 2022

Nitrogen (N) is ubiquitously found in bioactive molecules, pharmaceutical agents, and organic functional materials. Accordingly, development of new C–N bond-forming catalysis has been one the long-standing research subjects synthetic chemistry. In this Perspective, recent advances highly selective amination reactions with electrophilic reagents are described: by taking advantage concept nitrogen umpolung, otherwise challenging aminofunctionalizations, such as hydroamination, aminoboration, carboamination, readily available feedstock-like alkenes alkynes possible, giving densely functionalized complex often chiral alkylamines high selectivity. The scope, limitations, reaction mechanism briefly summarized.

Language: Английский

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Weak-Coordination in C–H Bond Functionalizations Catalyzed by 3d Metals

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(6), P. 3452 - 3506

Published: March 3, 2022

Transition-metal-catalyzed C–H bond functionalizations have had an enormous influence on organic synthesis in recent times. However, the use of low-abundance 4d and 5d metals is almost inevitable, they are high demand. This will be a cause concern, hence, it important to develop methods based 3d metals, which widely present Earth's crust. In this regard, metal catalysts or their precursors for catalysis, general, functionalizations, particular, has gained significant momentum The major development catalytic with been achieved predominantly strongly coordinating directing groups such as pyridyl, pyrimidinyl, pyrazolyl, 8-amino-quinolinyl groups. Thus, prefunctionalization substrates these necessary, contradicts step- atom-economy activation. commonly available functional aldehyde, ketone, carboxylic acid, amide, hydroxy, N-oxides loosely bind through weak-coordination. These weakly orient activate regioselectively without need preinstalled Although challenging, contemporary topic actively pursued by many researchers Through article, we provide comprehensive overview metal-catalyzed, coordinating, directing-group-enabled reported until March 2021.

Language: Английский

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Cobalt-Catalyzed Enantioselective C–H Arylation of Indoles

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(2), P. 798 - 806

Published: Jan. 10, 2022

Atropoisomeric (hetero)biaryls are scaffolds with increasing importance in the pharmaceutical and agrochemical industries. Although it is most obvious disconnection to construct such compounds, direct enantioselective C–H arylation through concomitant induction of chiral information remains extremely challenging uncommon. Herein, unprecedented earth-abundant 3d-metal-catalyzed atroposelective reported, furnishing rare atropoisomeric C2-arylated indoles. Kinetic studies DFT computation revealed an uncommon mechanism for this asymmetric transformation, oxidative addition being rate- enantio-determining step. Excellent stereoselectivities were reached (up 96% ee), while using unusual N-heterocyclic carbene ligand bearing essential remote substituent. Attractive dispersion interactions along positive C–H---π exerted by identified as key factors guarantee excellent enantioselection.

Language: Английский

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Cobalt/Salox‐Catalyzed Enantioselective C−H Functionalization of Arylphosphinamides

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(25)

Published: April 6, 2022

Previous methods on CoIII -catalyzed asymmetric C-H activation rely the use of tailor-made cyclopentadienyl-ligated complexes, which require lengthy steps for preparation. Herein, we report an unprecedented enantioselective functionalization enabled by a simple cobalt/salicyloxazoline (Salox) catalysis. The chiral Salox ligands can be easily prepared in one step from salicylonitrile and amino alcohols. A broad range P-stereogenic compounds were synthesized high yields with excellent enantioselectivities (45 examples, up to 99 % yield >99 ee). isolation characterization several intermediates provided insights into generation active catalytic cobalt species, action Salox, mode stereocontrol.

Language: Английский

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Enantio‐ and Regioselective Electrooxidative Cobalt‐Catalyzed C−H/N−H Annulation with Alkenes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(11)

Published: Jan. 20, 2023

In recent years, the merging of electrosynthesis with 3d metal catalyzed C-H activation has emerged as a sustainable and powerful technique in organic synthesis. Despite impressive advantages, development an enantioselective version remains elusive poses daunting challenge. Herein, we report first electrooxidative cobalt-catalyzed enantio- regioselective C-H/N-H annulation olefins using undivided cell at room temperature (up to 99 % ee). t Bu-Salox, rationally designed Salox ligand bearing bulky tert-butyl group ortho-position phenol, was found be crucial for this asymmetric reaction. A strong cooperative effect between Bu-Salox 3,4,5-trichloropyridine enabled highly more challenging α-olefins without secondary bond interactions 96 ee 97 : 3 rr). Cyclovoltametric studies, preparation, characterization, transformation cobaltacycle intermediates shed light on mechanism

Language: Английский

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Photoinduced Copper-Catalyzed Late-Stage Azidoarylation of Alkenes via Arylthianthrenium Salts

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(25), P. 13542 - 13548

Published: June 12, 2023

The arylethylamine pharmacophore is conserved across a range of biologically active natural products and pharmaceuticals, particularly in molecules that act on the central nervous system. Herein, we present photoinduced copper-catalyzed azidoarylation alkenes at late stage with arylthianthrenium salts, allowing access to highly functionalized acyclic (hetero)arylethylamine scaffolds are otherwise difficult access. A mechanistic study consistent rac-BINAP-CuI-azide (2) as photoactive catalytic species. We show utility new method by expedient synthesis racemic melphalan four steps through C-H functionalization.

Language: Английский

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Atroposelective isoquinolinone synthesis through cobalt-catalysed C–H activation and annulation

Nature Synthesis, Journal Year: 2022, Volume and Issue: 1(9), P. 709 - 718

Published: July 18, 2022

Language: Английский

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Single‐Step Synthesis of Atropisomers with Vicinal C−C and C−N Diaxes by Cobalt‐Catalyzed Atroposelective C−H Annulation

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(39)

Published: Aug. 2, 2022

The atroposelective synthesis of atropisomers with vicinal diaxes remains rare and challenging, due to the steric influence between two axes their unique topology. Herein, we disclose a single-step construction C-C C-N chiral by cyclopentadiene (Cp)-free cobalt-catalyzed intramolecular C-H annulation, providing desired diaxial structures decent stereocontrols both (up >99 % ee 70 : 1 dr). optically pure products bearing fluorophores show circular polarized luminescence (CPL) properties, being candidate materials for potential CPL applications. Atropisomerization experiments density function theory (DFT) calculations are conducted study rotational barriers rotation pathways diaxes.

Language: Английский

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Cobalt(III)/Chiral Carboxylic Acid‐Catalyzed Enantioselective Synthesis of Benzothiadiazine‐1‐oxides via C−H Activation

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(28)

Published: May 2, 2022

Abstract Among sulfoximine derivatives containing a chiral sulfur center, benzothiadiazine‐1‐oxides are important for applications in medicinal chemistry. Here, we report that the combination of an achiral cobalt(III) catalyst and pseudo‐ C 2 ‐symmetric H 8 ‐binaphthyl carboxylic acid enables asymmetric synthesis from sulfoximines dioxazolones via enantioselective C−H bond cleavage. With optimized protocol, with several functional groups can be accessed high enantioselectivity.

Language: Английский

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Base‐Promoted Electrochemical Co^II‐catalyzed Enantioselective C−H Oxygenation

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(21)

Published: March 20, 2023

Metalla-electrocatalyzed C-H oxygenation represents one of the most straightforward and sustainable approaches to access valuable oxygenated molecules. Despite significant advances, development enantioselective electrochemical reaction is very challenging remains elusive. Herein, we described first CoII -catalyzed alkoxylation. A broad range enantioenriched alkoxylated phosphinamides were obtained in good yields with excellent enantioselectivities (up 98 % yield >99 ee). An unusual cobalt(III) alcohol complex was prepared fully characterized, which proven be a key intermediate this alkoxylation reaction. Mechanistic studies revealed that oxidation CoIII CoIV facilitated by base whole process proceeded through cobalt(III/IV/II) catalytic cycle.

Language: Английский

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