Enantioselective C−H Activation with Earth‐Abundant 3d Transition Metals

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(37), P. 12803 - 12818

Published: May 11, 2019

Molecular syntheses largely rely on time- and labour-intensive prefunctionalization strategies. In contrast, C-H activation represents an increasingly powerful approach that avoids lengthy of prefunctionalized substrates, with great potential for drug discovery, the pharmaceutical industry, material sciences, crop protection, among others. The enantioselective functionalization omnipresent bonds has emerged as a transformative tool step- atom-economical generation chiral molecular complexity. However, this rapidly growing research area remains dominated by noble transition metals, prominently featuring toxic palladium, iridium rhodium catalysts. Indeed, despite significant achievements, use inexpensive sustainable 3d metals in asymmetric activations is still clearly its infancy. Herein, we discuss remarkable recent progress transformations via organometallic base up to April 2019.

Language: Английский

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Indole Synthesis by Rhodium(III)‐Catalyzed Hydrazine‐Directed CH Activation: Redox‐Neutral and Traceless by NN Bond Cleavage

Angewandte Chemie International Edition, Journal Year: 2013, Volume and Issue: 52(47), P. 12426 - 12429

Published: Sept. 25, 2013

Fishing for complements! There is an alternative to the useful Fischer indole synthesis. The new method utilizes same retrosynthetic disconnection but based on a RhIII-catalyzed directed CH activation step and successive coupling with alkynes.

Language: Английский

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Construction of Quaternary Stereocenters by Palladium‐Catalyzed Carbopalladation‐Initiated Cascade Reactions

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(6), P. 1562 - 1573

Published: June 30, 2018

Abstract The enantioselective synthesis of molecules containing quaternary stereocenters is a field intense research interest and development. Among the known organic transformations, carbopalladation‐initiated domino transformations constitutes general method for construction compounds cyclic or spiro stereocenters. In this Minireview, recent achievements in palladium‐catalyzed Heck/C−H functionalizations developments processes are summarized.

Language: Английский

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Comparative Catalytic Activity of Group 9 [Cp*M^III] Complexes: Cobalt‐Catalyzed CH Amidation of Arenes with Dioxazolones as Amidating Reagents

Angewandte Chemie International Edition, Journal Year: 2015, Volume and Issue: 54(47), P. 14103 - 14107

Published: Sept. 25, 2015

A procedure for the [Cp*Co(III)]-catalyzed direct C-H amidation of arenes with dioxazolone has been developed. This reaction proceeds under straightforward and mild conditions a broad range substrates, including anilides. comparative study on catalytic activity Group 9 [{Cp*MCl2}2] complexes revealed unique efficiency cobalt catalyst.

Language: Английский

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Stereoselective Synthesis of Chiral α‐Amino‐β‐Lactams through Palladium(II)‐Catalyzed Sequential Monoarylation/Amidation of C(sp³)H Bonds

Angewandte Chemie International Edition, Journal Year: 2013, Volume and Issue: 52(51), P. 13588 - 13592

Published: Oct. 31, 2013

Give Me an Ar, give N! Arylation of the methyl group in a simple derivative readily available alanine under palladium catalysis was followed by intramolecular amidation at same position to chiral α-amino-β-lactams with wide range aryl substituents (see scheme; Phth=phthaloyl). The were obtained moderate high yields good functional-group tolerance and diastereoselectivity. As service our authors readers, this journal provides supporting information supplied authors. Such materials are peer reviewed may be re-organized for online delivery, but not copy-edited or typeset. Technical support issues arising from (other than missing files) should addressed Please note: publisher is responsible content functionality any Any queries content) directed corresponding author article.

Language: Английский

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Cobalt(III)‐Catalyzed Directed CH Coupling with Diazo Compounds: Straightforward Access towards Extended π‐Systems

Angewandte Chemie International Edition, Journal Year: 2015, Volume and Issue: 54(15), P. 4508 - 4511

Published: Feb. 20, 2015

The first highly efficient and scalable cobalt-catalyzed directed C-H functionalization with carbene precursors is presented. This methodology provides a modular route towards new class of conjugated polycyclic hydrocarbons tunable emission wavelengths both in solution the solid state.

Language: Английский

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Air‐Stable Carbonyl(pentamethylcyclopentadienyl)cobalt Diiodide Complex as a Precursor for Cationic (Pentamethylcyclopentadienyl)cobalt(III) Catalysis: Application for Directed C‐2 Selective CH Amidation of Indoles

Advanced Synthesis & Catalysis, Journal Year: 2014, Volume and Issue: 356(7), P. 1491 - 1495

Published: March 27, 2014

Abstract The readily available carbonyl(pentamethylcyclopentadienyl)cobalt diiodide complex [Cp*Co(CO)I 2 ] was successfully utilized as the precursor of a cationic cobalt(III) active catalyst for directed CH bond functionalization. Cp*Co(CO)I (2.5–1.25 mol%), in combination with silver hexafluoroantimonate (AgSbF 6 ) and potassium acetate (KOAc), efficiently catalyzed C‐2 selective amidation indoles sulfonyl azides, corresponding products were obtained 85–98 % yield. magnified image

Language: Английский

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Mechanochemistry for Organic Chemists: An Update

European Journal of Organic Chemistry, Journal Year: 2017, Volume and Issue: 2018(1), P. 18 - 33

Published: Nov. 6, 2017

We provide a brief overview of recent advances in the use mechanochemical techniques for synthesis organic molecules and materials, highlighting selected examples transformations mechanistic studies, especially those that illustrate chemical reactions or syntheses molecular targets have remained elusive to conventional solution techniques.

Language: Английский

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Cp*Co^III Catalyzed Site‐Selective CH Activation of Unsymmetrical O‐Acyl Oximes: Synthesis of Multisubstituted Isoquinolines from Terminal and Internal Alkynes

Angewandte Chemie International Edition, Journal Year: 2015, Volume and Issue: 54(44), P. 12968 - 12972

Published: Sept. 28, 2015

The synthesis of isoquinolines by site-selective C-H activation O-acyl oximes with a Cp*Co(III) catalyst is described. In the presence this catalyst, various unsymmetrically substituted selectively occurred at sterically less hindered site, and reactions terminal as well internal alkynes afforded corresponding products in up to 98 % yield. Whereas catalyzed system proceeded high site selectivity (15:1 20:1), use Cp*Rh(III) catalysts led low selectivities and/or yields when unsymmetrical were used. Deuterium labeling studies indicate clear difference step under catalysis.

Language: Английский

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Advancing the Logic of Chemical Synthesis: C−H Activation as Strategic and Tactical Disconnections for C−C Bond Construction

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(29), P. 15767 - 15790

Published: Oct. 19, 2020

The design of synthetic routes by retrosynthetic logic is decisively influenced the transformations available. Transition-metal-catalyzed C-H activation has emerged as a powerful strategy for C-C bond formation, with myriad methods developed diverse substrates and coupling partners. However, its uptake in total synthesis been tepid, partially due to their apparent intractability, well lack comprehensive guidelines implementation. This Review addresses these issues offers guide identify opportunities generate bonds processes. By comparing syntheses accomplished using traditional approaches recent methods, this demonstrates how enabled construction led more efficient strategies, execution previously unattainable tactical maneuvers. Finally, shortcomings existing processes are highlighted; illustrates some highlighted can be further economized adopting next-generation ligand-enabled approaches.

Language: Английский

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