Mechanisms of Nickel-Catalyzed Cross-Coupling Reactions

Trends in Chemistry, Journal Year: 2019, Volume and Issue: 1(9), P. 830 - 844

Published: Sept. 13, 2019

Language: Английский

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Alcohols as Latent Coupling Fragments for Metallaphotoredox Catalysis: sp³–sp² Cross-Coupling of Oxalates with Aryl Halides

Journal of the American Chemical Society, Journal Year: 2016, Volume and Issue: 138(42), P. 13862 - 13865

Published: Oct. 9, 2016

Alkyl oxalates, prepared from their corresponding alcohols, are engaged for the first time as carbon radical fragments in metallaphotoredox catalysis. In this report, we demonstrate that native organic functional groups, can be readily activated with simple oxalyl chloride to become precursors a net redox-neutral Csp3–Csp2 cross-coupling broad range of aryl halides. This alcohol-activation coupling is successfully applied functionalization naturally occurring steroid and expedient synthesis medicinally relevant drug lead.

Language: Английский

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Ni-Catalyzed Reductive Coupling of Electron-Rich Aryl Iodides with Tertiary Alkyl Halides

Journal of the American Chemical Society, Journal Year: 2018, Volume and Issue: 140(43), P. 14490 - 14497

Published: Oct. 8, 2018

This work illustrates the reductive coupling of electron-rich aryl halides with tertiary alkyl under Ni-catalyzed cross-electrophile conditions, which offers an efficient protocol for construction all carbon quaternary stereogenic centers. The mild and easy-to-operate reaction tolerates a wide range functional groups. utility this method is manifested by preparation cyclotryptamine derivatives, wherein successful incorporation 7-indolyl moieties particular interest as numerous naturally occurring products are composed these key scaffolds. DFT calculations have been carried out to investigate proposed radical chain double oxidative addition pathways, provide useful mechanistic insights into part that takes place in solution.

Language: Английский

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Catalytic Enantioselective Arylboration of Alkenylarenes

Angewandte Chemie International Edition, Journal Year: 2016, Volume and Issue: 56(3), P. 851 - 855

Published: Dec. 21, 2016

Abstract A method for the catalytic enantioselective arylboration of alkenylarenes is disclosed. The reaction leads to formation 1,1‐diarylalkanes that also incorporate an additional pinacol boronic ester which can be easily transformed a variety groups. products are formed with excellent diastereoselectivities and enantioselectivities.

Language: Английский

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On the Nature of C(sp³)–C(sp²) Bond Formation in Nickel-Catalyzed Tertiary Radical Cross-Couplings: A Case Study of Ni/Photoredox Catalytic Cross-Coupling of Alkyl Radicals and Aryl Halides

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(15), P. 7225 - 7234

Published: March 20, 2020

The merger of photoredox and nickel catalysis has enabled the construction quaternary centers. However, mechanism, role ligand, effect spin state for this transformation related Ni-catalyzed cross-couplings involving tertiary alkyl radicals in combination with bipyridine diketonate ligands remain unknown. Several mechanisms have been proposed, all invoking a key Ni(III) species prior to undergoing irreversible inner-sphere reductive elimination. In work, we used open-shell dispersion-corrected DFT calculations, quasi-classical dynamics experiments study detail mechanism carbon–carbon bond formation Ni bipyridine- diketonate-based catalytic systems. These calculations revealed that access high states (e.g., triplet tetrahedral Ni(II) species) is critical effective radical cross-coupling radicals. Further, these disparate C–C formation. Specifically, contrary neutral Ni-bipyridyl system, lead directly corresponding products via an outer-sphere elimination step from intermediates. Implications design new transformations are discussed.

Language: Английский

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Univariate classification of phosphine ligation state and reactivity in cross-coupling catalysis

Science, Journal Year: 2021, Volume and Issue: 374(6565), P. 301 - 308

Published: Oct. 15, 2021

Which phosphines squeeze together? Phosphine ligands coordinated to palladium and nickel are essential tools for assembling the backbones of pharmaceutical compounds. For decades, descriptors that characterize spatial bulk have helped guide phosphine optimization. However, these tend apply ideal geometries a single ligand. Newman-Stonebraker et al . introduce descriptor considers how ligand conformation might change in crowded environment. Specifically, they found minimum percentage buried volume accurately predicts when one or two particular will coordinate metal center, frequently key determinant successful catalysis. —JSY

Language: Английский

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Nickel-catalyzed formation of quaternary carbon centers using tertiary alkyl electrophiles

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(6), P. 4162 - 4184

Published: Jan. 1, 2021

This review provides a comprehensive summary of recent advances in nickel-catalyzed reactions employing tertiary alkyl electrophiles for the construction quaternary carbon centers.

Language: Английский

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Copper-Catalyzed Arylation of Benzylic C–H bonds with Alkylarenes as the Limiting Reagents

Journal of the American Chemical Society, Journal Year: 2017, Volume and Issue: 139(23), P. 7709 - 7712

Published: May 31, 2017

A novel copper-catalyzed arylation of benzylic C–H bonds with nucleophilic arylboronic acids has been developed that provides an efficient way to synthesize various 1,1-diarylalkanes a broad substrate scope and excellent functional group compatibility. The reactions occur at room temperature using alkylarenes as the limiting reagents, which allows access more valuable complex bioactive compounds.

Language: Английский

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Preparation of Quaternary Centers via Nickel-Catalyzed Suzuki–Miyaura Cross-Coupling of Tertiary Sulfones

Journal of the American Chemical Society, Journal Year: 2017, Volume and Issue: 140(1), P. 78 - 81

Published: Dec. 7, 2017

We describe the development of a nickel-catalyzed Suzuki–Miyaura cross-coupling tertiary benzylic and allylic sulfones with arylboroxines. A variety sulfones, which can easily be prepared via deprotonation–alkylation route, were reacted to afford symmetric unsymmetric quaternary products in good yields. highlight use either BrettPhos or Doyle's phosphines as effective ligands for these challenging desulfonative coupling reactions. The utility this methodology was demonstrated concise synthesis vitamin D receptor modulator analogue.

Language: Английский

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Modular Synthesis of Enantioenriched 1,1,2-Triarylethanes by an Enantioselective Arylboration and Cross-Coupling Sequence

ACS Catalysis, Journal Year: 2017, Volume and Issue: 7(4), P. 2425 - 2429

Published: Feb. 17, 2017

An enantioselective Cu/Pd-catalyzed borylative coupling of styrenes with aryl/alkenyl iodides was realized using a chiral sulfoxide-phosphine (SOP) ligand. Enantioenriched 1,1-diarylethyl and β-aryl-homoallylic boronates are readily prepared. A streamlined procedure merging arylboration subsequent Pd-catalyzed Suzuki–Miyaura cross-coupling enables the modular assembly enantioenriched 1,1,2-triarylethanes, including two medicinally important small-molecule targets.

Language: Английский

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