Reductive Arylation Research Articles

Cover Feature: Electrochemical Reductive Arylation of Nitroarenes with Arylboronic Acids (ChemSusChem 24/2021)

The Cover Feature shows the novel electrochemical reductive arylation of arylboronic acids with nitroarenes. A variety of diarylamines has been synthesized without the need for transition-metal catalysts. The reaction can be scaled up efficiently in a flow cell, and several derivatization reactions were carried out smoothly. More information can be found in the Communication by D. Wang et al.

A relay catalysis strategy for enantioselective nickel-catalyzed migratory hydroarylation forming chiral α-aryl alkylboronates

A relay catalysis strategy for enantioselective nickel-catalyzed migratory hydroarylation forming chiral α-aryl alkylboronates

Electrochemical Reductive Arylation of Nitroarenes with Arylboronic Acids.

The synthesis of diarylamine is extremely important in organic chemistry. Herein, a novel electrochemical reductive arylation of nitroarenes with arylboronic acids was developed. A variety of diarylamines were synthesized without the need for transition-metal catalysts. The reaction could be scaled up efficiently in a flow cell and several derivatization reactions were carried out smoothly. Cyclic voltammetry experiments and mechanism studies showed that acetonitrile, formic acid, and triethyl phosphite all played a role in promoting this reductive arylation transformation.

Reductive Arylation of Aliphatic and Aromatic Aldehydes with Cyanoarenes by Electrolysis for the Synthesis of Alcohols.

An electroreductive arylation reaction of aliphatic and aromatic aldehydes as well as ketones with electro-deficient (hetero)arenes is described. A variety of cyano(hetero)arenes and carbonyl compounds, especially aliphatic aldehydes, have been examined, providing secondary and tertiary alcohols in moderate to good yields. Mechanistic studies, including cyclic voltammetry (CV), electron paramagnetic resonance (EPR), and divided-cell experiments, support the generation of aliphatic ketyl radicals and persistent heteroaryl radical anions via cathodic reduction followed by radical-radical cross-coupling.

SmI2/Sm-Arylboronic Esters Combination for the Reductive Arylation of Aromatic Tertiary Amides

SmI₂/Sm-Arylboronic Esters Combination for the Reductive Arylation of Aromatic Tertiary Amides

Nickel-catalyzed asymmetric reductive arylation of α-chlorosulfones with aryl halides.

We report an asymmetric Ni-catalyzed reductive cross-coupling of aryl/heteroaryl halides with racemic α-chlorosulfones to afford enantioenriched sulfones. The reaction tolerates a variety of functional groups under mild reaction conditions, which complements the current methods. The utility of this work was demonstrated by facile late-stage functionalization of commercial drugs.

Reductive Arylation of Amides via a Nickel-Catalyzed Suzuki-Miyaura-Coupling and Transfer-Hydrogenation Cascade.

We report a means to achieve the addition of two disparate nucleophiles to the amide carbonyl carbon in a single operational step. Our method takes advantage of non-precious-metal catalysis and allows for the facile conversion of amides to chiral alcohols via a one-pot Suzuki-Miyaura cross-coupling/transfer-hydrogenation process. This study is anticipated to promote the development of new transformations that allow for the conversion of carboxylic acid derivatives to functional groups bearing stereogenic centers via cascade processes.

Reductive Arylation of Amides via a Nickel‐Catalyzed Suzuki–Miyaura‐Coupling and Transfer‐Hydrogenation Cascade

AbstractWe report a means to achieve the addition of two disparate nucleophiles to the amide carbonyl carbon in a single operational step. Our method takes advantage of non‐precious‐metal catalysis and allows for the facile conversion of amides to chiral alcohols via a one‐pot Suzuki–Miyaura cross‐coupling/transfer‐hydrogenation process. This study is anticipated to promote the development of new transformations that allow for the conversion of carboxylic acid derivatives to functional groups bearing stereogenic centers via cascade processes.

Nickel-Catalyzed Reductive Aryl Thiocarbonylation of Alkene via Thioester Group Transfer Strategy.

Herein reported is a nickel-catalyzed reductive aryl thiocarbonylation of alkene via thioester group transfer strategy by using simple and readily available thioesters. In contrast to traditional activation of weaker C(acyl)-S bond, the C(acyl)-C bond of thioester was selectively cleaved to enable this reaction under mild conditions. Furthermore, this approach features operational simplicity and broad substrate scope, providing a complementary and practical route for thioester synthesis without requiring toxic thiol or CO gas.

Nickel-Catalyzed Enantioselective Reductive Aryl Fluoroalkenylation

Nickel-Catalyzed Enantioselective Reductive Aryl Fluoroalkenylation

Nickel-Catalyzed Enantioselective Reductive Aryl Fluoroalkenylation of Alkenes

Enantioselective Ni-catalyzed reductive aryl monofluoroalkenylation of alkenes between aryl bromides and gem-difluoroalkenes has been developed. The reaction proceeding under room temperature and b...

Nickel-catalyzed reductive coupling of glucosyl halides with aryl/vinyl halides enabling β-selective preparation of C-aryl/vinyl glucosides

This work describes stereoselective preparation of β- C -aryl/vinyl glucosides via mild Ni-catalyzed reductive arylation and vinylation of C 1-glucosyl halides with aryl and vinyl halides. A broad range of aryl halides and vinyl halides were employed to yield C -aryl/vinyl glucosides in 42%–93% yields. Good to excellent β-selectivities were obtained for C -glucosides by using tridentate ligand.

Deaminative Reductive Arylation Enabled by Nickel/Photoredox Dual Catalysis.

Described is a cross-electrophilic, deaminative coupling strategy harnessing Katritzky salts as a new species of electrophile in Ni/photoredox dual catalytic reductive cross-coupling reactions. Distinguishing features of this arylation protocol include its mild reaction conditions, high chemoselectivity, and adaptability to a variety of complex substrates [i.e., pyridinium salts derived from amines and partners derived from (hetero)aryl bromides].

Reductive diazotation of carbon nanotubes: an experimental and theoretical selectivity study.

The reaction of neutral single-walled carbon nanotubes (SWCNTs) with diazonium salts proceeds with a high selectivity towards metallic carbon nanotube species; this reaction is well-understood and the mechanism has been elucidated. In the present joint theoretical and experimental study, we investigate the reaction of negatively charged SWCNTs - carbon nanotubides - with diazonium salts. Our density functional theory calculations predict a stronger binding of the aryl diazonium cations to charged metallic SWCNTs species and therefore lead to a preferential addend binding in the course of the reaction. The Raman resonance profile analysis on the reductive arylation of carbon nanotubides obtained by the solid state intercalation approach with potassium in varying concentrations confirms the predicted preferred functionalization of metallic carbon nanotubes. Furthermore, we were also able to show that the selectivity for metallic SWCNT species could be further increased when low potassium concentrations (K : C < 1 : 200) are used for an initial selective charging of the metallic species. Further insights into the nature of the bound addends were obtained by coupled thermogravimetric analysis of the functionalized samples.

Ruthenium‐Catalyzed Reductive Arylation of N‐(2‐Pyridinyl)amides with Isopropanol and Arylboronate Esters

A new three-component reductive arylation of amides with stable reactants (iPrOH and arylboronate esters), making use of a 2-pyridinyl (Py) directing group, is described. The N-Py-amide substrates are readily prepared from carboxylic acids and PyNH2 , and the resulting N-Py-1-arylalkanamine reaction products are easily transformed into the corresponding chlorides by substitution of the HN-Py group with HCl. The 1-aryl-1-chloroalkane products allow substitution and cross-coupling reactions. Therefore, a general protocol for the transformation of carboxylic acids into a variety of functionalities is obtained. The Py-NH2 by-product can be recycled.

Diastereoselective Reductive Arylation of Internal Alkynes

Diastereoselective Reductive Arylation of Internal Alkynes

Copper-Catalyzed Radical Reductive Arylation of Styrenes with Aryl Iodides Mediated by Zinc in Water.

A copper/aniline catalyst system enables the radical arylation of styrenes using aryl iodides mediated by zinc in water. This transformation provides an efficient synthetic methodology for the convenient synthesis of diarylethane.

Nickel‐Catalyzed Umpolung Arylation of Ambiphilic α‐Bromoalkyl Boronic Esters

AbstractA nickel‐catalyzed reductive arylation of ambiphilic α‐bromoalkyl boronic esters with aryl halides is described. This platform provides an unrecognized opportunity to promote the catalytic umpolung reactivity of ambiphilic reagents with aryl halides, thus unlocking a new cross‐coupling strategy that complements existing methods for the preparation of densely functionalized alkyl‐substituted organometallic reagents from simple and readily accessible precursors.

Nickel-Catalyzed Umpolung Arylation of Ambiphilic α-Bromoalkyl Boronic Esters.

A nickel-catalyzed reductive arylation of ambiphilic α-bromoalkyl boronic esters with aryl halides is described. This platform provides an unrecognized opportunity to promote the catalytic umpolung reactivity of ambiphilic reagents with aryl halides, thus unlocking a new cross-coupling strategy that complements existing methods for the preparation of densely functionalized alkyl-substituted organometallic reagents from simple and readily accessible precursors.

Visible-Light-Triggered Directly Reductive Arylation of Carbonyl/Iminyl Derivatives through Photocatalytic PCET.

The first visible-light-mediated radical-radical cross-coupling strategy that enables the direct arylation of carbonyl/iminyl derivatives in the presence of Et3N has been realized. Such an atom-economical protocol furnishes a broad scope of arylation products such as secondary/tertiary alcohols and amines via a PCET process that facilitates the challenging reduction of C═X (X = O, N). Mechanistic investigation indicates two photocatalytic redox cycles were involved in the process, and Et3N was proved to serve as a dual reductant and proton donor. Moreover, the isolated byproducts and controlled experiments could be considered as powerful supporting evidence for our hypothesis.