Browse
Submit Data
Databases
API
Help

Dataset Information

47 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Enantioselective benzylic C-H arylation via photoredox and nickel dual catalysis.

ABSTRACT: The asymmetric cross-coupling reaction is developed as a straightforward strategy toward 1,1-diaryl alkanes, which are a key skeleton in a series of natural products and bioactive molecules in recent years. Here we report an enantioselective benzylic C(sp³)-H bond arylation via photoredox/nickel dual catalysis. Sterically hindered chiral biimidazoline ligands are designed for this asymmetric cross-coupling reaction. Readily available alkyl benzenes and aryl bromides with various functional groups tolerance can be easily and directly transferred to useful chiral 1,1-diaryl alkanes including pharmaceutical intermediates and bioactive molecules. This reaction proceeds smoothly under mild conditions without the use of external redox reagents.

SUBMITTER: Cheng X

PROVIDER: S-EPMC6685991 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Enantioselective benzylic C-H arylation via photoredox and nickel dual catalysis.

Cheng Xiaokai X Lu Huangzhe H Lu Zhan Z

Nature communications 20190807 1

The asymmetric cross-coupling reaction is developed as a straightforward strategy toward 1,1-diaryl alkanes, which are a key skeleton in a series of natural products and bioactive molecules in recent years. Here we report an enantioselective benzylic C(sp3)-H bond arylation via photoredox/nickel dual catalysis. Sterically hindered chiral biimidazoline ligands are designed for this asymmetric cross-coupling reaction. Readily available alkyl benzenes and aryl bromides with various funct ...[more]

PMID: 31391466

Similar Datasets

Catalytic enantioselective reductive domino alkyl arylation of acrylates via nickel/photoredox catalysis.

Project description:Nonsteroidal anti-inflammatory drug derivatives (NSAIDs) are an important class of medications. Here we show a visible-light-promoted photoredox/nickel catalyzed approach to construct enantioenriched NSAIDs via a three-component alkyl arylation of acrylates. This reductive cross-electrophile coupling avoids preformed organometallic reagents and replaces stoichiometric metal reductants by an organic reductant (Hantzsch ester). A broad range of functional groups are well-tolerated under mild conditions with high enantioselectivities (up to 93% ee) and good yields (up to 90%). A study of the reaction mechanism, as well as literature precedence, enabled a working reaction mechanism to be presented. Key steps include a reduction of the alkyl bromide to the radical, Giese addition of the alkyl radical to the acrylate and capture of the α-carbonyl radical by the enantioenriched nickel catalyst. Reductive elimination from the proposed Ni(III) intermediate generates the product and forms Ni(I).

| S-EPMC8595378 | biostudies-literature

Direct α-Arylation/Heteroarylation of 2-Trifluoroboratochromanones via Photoredox/Nickel Dual Catalysis.

Project description:Utilizing photoredox/nickel dual catalysis, diverse flavanones have been synthesized by coupling novel 2-trifluoroboratochromanone building blocks with aryl and heteroaryl bromide partners. The newly reported trifluoroboratochromanones can be easily accessed from the corresponding chromones on multigram scale. This represents a general route for accessing natural and unnatural flavanones that were previously formed through a synthetically more restrictive ring closure route from chalcone precursors.

| S-EPMC5295361 | biostudies-literature

Deaminative Reductive Arylation Enabled by Nickel/Photoredox Dual Catalysis.

Project description: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].

| S-EPMC6512806 | biostudies-literature

Enantioselective Decarboxylative Arylation of α-Amino Acids via the Merger of Photoredox and Nickel Catalysis.

Project description:An asymmetric decarboxylative Csp(3)-Csp(2) cross-coupling has been achieved via the synergistic merger of photoredox and nickel catalysis. This mild, operationally simple protocol transforms a wide variety of naturally abundant α-amino acids and readily available aryl halides into valuable chiral benzylic amines in high enantiomeric excess, thereby producing motifs found in pharmacologically active agents.

| S-EPMC4862596 | biostudies-literature

Thioetherification via Photoredox/Nickel Dual Catalysis.

Project description:Hypervalent alkylsilicates represent new and readily accessible precursors for the generation of alkyl radicals under photoredox conditions. Alkyl radicals generated from such silicates serve as effective hydrogen atom abstractors from thiols, furnishing thiyl radicals. The reactive sulfur species generated in this manner can be funneled into a nickel-mediated cross-coupling cycle employing aromatic bromides to furnish thioethers. The serendipitous discovery of this reaction and its utilization for the thioetherification of various aryl and heteroaryl bromides with a diverse array of thiols is described. The S-H selective H atom abstraction event enables a wide range of functional groups, including those bearing protic moieties, to be tolerated.

| S-EPMC4854196 | biostudies-literature

Asymmetric benzylic C(sp3)-H acylation via dual nickel and photoredox catalysis.

Project description:Asymmetric C(sp3)-H functionalization is a persistent challenge in organic synthesis. Here, we report an asymmetric benzylic C-H acylation of alkylarenes employing carboxylic acids as acyl surrogates for the synthesis of α-aryl ketones via nickel and photoredox dual catalysis. This mild yet straightforward protocol transforms a diverse array of feedstock carboxylic acids and simple alkyl benzenes into highly valuable α-aryl ketones with high enantioselectivities. The utility of this method is showcased in the gram-scale synthesis and late-stage modification of medicinally relevant molecules. Mechanistic studies suggest a photocatalytically generated bromine radical can perform benzylic C-H cleavage to activate alkylarenes as nucleophilic coupling partners which can then engage in a nickel-catalyzed asymmetric acyl cross-coupling reaction. This bromine-radical-mediated C-H activation strategy can be also applied to the enantioselective coupling of alkylarenes with chloroformate for the synthesis of chiral α-aryl esters.

| S-EPMC8192574 | biostudies-literature

Enantioselective Synthesis of N-Benzylic Heterocycles by Ni/Photoredox Dual Catalysis.

Project description:An asymmetric cross-coupling of α-N-heterocyclic trifluoroborates with aryl bromides using Ni/photoredox dual catalysis has been developed. This C(sp2)-C(sp3) cross-coupling provides access to pharmaceutically relevant chiral N-benzylic heterocycles in good to excellent enantioselectivity when bioxazolines (BiOX) are used as the chiral ligand. High-throughput experimentation significantly streamlined reaction development by identifying BiOX ligands for further investigation and by allowing for rapid optimization of conditions for new trifluoroborate salts.

| S-EPMC10326726 | biostudies-literature

Asymmetric β-arylation of cyclopropanols enabled by photoredox and nickel dual catalysis.

Project description:The enantioselective functionalization and transformation of readily available cyclopropyl compounds are synthetically appealing yet challenging topics in organic synthesis. Here we report an asymmetric β-arylation of cyclopropanols with aryl bromides enabled by photoredox and nickel dual catalysis. This dual catalytic transformation features a broad substrate scope and good functional group tolerance at room temperature, providing facile access to a wide array of enantioenriched β-aryl ketones bearing a primary alcohol moiety in good yields with satisfactory enantioselectivities (39 examples, up to 83% yield and 90% ee). The synthetic value of this protocol was illustrated by the concise asymmetric construction of natural product calyxolane B analogues.

| S-EPMC8905987 | biostudies-literature

Single-Electron Transmetalation: Protecting-Group-Independent Synthesis of Secondary Benzylic Alcohol Derivatives via Photoredox/Nickel Dual Catalysis.

Project description:Protecting-group-independent cross-coupling of α-alkoxyalkyl- and α-acyloxyalkyltrifluoroborates with aryl and heteroaryl bromides is achieved through application of photoredox/nickel dual catalysis. Reactions occur under exceptionally mild conditions, with outstanding functional group compatibility and excellent observed tolerance of heteroarenes. This method offers expedient access to protected secondary benzylic alcohol motifs bearing benzyl, pivaloyl, and N,N-diisopropylcarbamoyl protecting groups.

| S-EPMC4900145 | biostudies-literature

A general strategy for organocatalytic activation of C-H bonds via photoredox catalysis: direct arylation of benzylic ethers.

Project description:Direct C-H functionalization and arylation of benzyl ethers has been accomplished via photoredox organocatalysis. The productive merger of a thiol catalyst and a commercially available iridium photoredox catalyst in the presence of household light directly affords benzylic arylation products in good to excellent yield. The utility of this methodology is further demonstrated in direct arylation of 2,5-dihydrofuran to form a single regioisomer.

| S-EPMC3988471 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data