Browse
Submit Data
Databases
API
Help

Dataset Information

45 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Three-component 1,2-carboamination of vinyl boronic esters via amidyl radical induced 1,2-migration.

ABSTRACT: Three-component 1,2-carboamination of vinyl boronic esters with alkyl/aryl lithium reagents and N-chloro-carbamates/carboxamides is presented. Vinylboron ate complexes generated in situ from the boronic ester and an organo lithium reagent are shown to react with readily available N-chloro-carbamates/carboxamides to give valuable 1,2-aminoboronic esters. These cascades proceed in the absence of any catalyst upon simple visible light irradiation. Amidyl radicals add to the vinylboron ate complexes followed by oxidation and 1,2-alkyl/aryl migration from boron to carbon to give the corresponding carboamination products. These practical cascades show high functional group tolerance and accordingly exhibit broad substrate scope. Gram-scale reaction and diverse follow-up transformations convincingly demonstrate the synthetic potential of this method.

SUBMITTER: You C

PROVIDER: S-EPMC8654000 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Three-component 1,2-carboamination of vinyl boronic esters via amidyl radical induced 1,2-migration.

You Cai C Studer Armido A

Chemical science 20211116 47

Three-component 1,2-carboamination of vinyl boronic esters with alkyl/aryl lithium reagents and N-chloro-carbamates/carboxamides is presented. Vinylboron ate complexes generated in situ from the boronic ester and an organo lithium reagent are shown to react with readily available N-chloro-carbamates/carboxamides to give valuable 1,2-aminoboronic esters. These cascades proceed in the absence of any catalyst upon simple visible light irradiation. Amidyl radicals add to the vin ...[more]

PMID: 35003609

Similar Datasets

Enantiospecific Trifluoromethyl-Radical-Induced Three-Component Coupling of Boronic Esters with Furans.

Project description:In the presence of trifluoromethylsulfonium reagents, boronate complexes derived from 2-lithio furan and non-racemic secondary and tertiary alkyl or aryl boronic esters undergo deborylative three-component coupling to give the corresponding 2,5-disubstituted furans with excellent levels of enantiospecificity. The process proceeds via the reaction of boronate complexes with a trifluoromethyl radical, which triggers 1,2-metallate rearrangement upon single-electron oxidation. Alternative electrophiles can also be used in place of trifluoromethylsulfonium reagents to effect similar three-component coupling reactions.

| S-EPMC5499725 | biostudies-literature

Visible-Light-Mediated Decarboxylative Radical Additions to Vinyl Boronic Esters: Rapid Access to γ-Amino Boronic Esters.

Project description:The synthesis of alkyl boronic esters by direct decarboxylative radical addition of carboxylic acids to vinyl boronic esters is described. The reaction proceeds under mild photoredox catalysis and involves an unprecedented single-electron reduction of an α-boryl radical intermediate to the corresponding anion. The reaction is amenable to a diverse range of substrates, including α-amino, α-oxy, and alkyl carboxylic acids, thus providing a novel method to rapidly access boron-containing molecules of potential biological importance.

| S-EPMC5838549 | biostudies-literature

Palladium-catalyzed three-component radical-polar crossover carboamination of 1,3-dienes or allenes with diazo esters and amines.

Project description:Herein, we report a visible-light-mediated palladium-catalyzed three-component radical-polar crossover carboamination of 1,3-dienes or allenes with diazo esters and amines, affording unsaturated γ- and ε-amino acid derivatives with diverse structures. In this methodology, the diazo compound readily transforms into a hybrid α-ester alkylpalladium radical with the release of dinitrogen. The radical intermediate selectively adds to the double bond of a 1,3-diene or allene, followed by the allylpalladium radical-polar crossover path and selective allylic substitution with the amine substrate, thereby leading to a single unsaturated γ- or ε-amino acid derivative. This approach proceeds under mild and simple reaction conditions and shows high functional group tolerance, especially in the incorporation of various bioactive molecules. The studies on scale-up reactions and diverse derivatizations highlight the practical utility of this multicomponent reaction protocol.

| S-EPMC10999982 | biostudies-literature

Carboamination of Unactivated Alkenes through Three-Component Radical Conjugate Addition.

Project description:Two-component Giese type radical additions are highly practical and established reactions. Herein, three-component radical conjugate additions of unactivated alkenes to Michael acceptors are reported. Amidyl radicals, oxidatively generated from ?-amido oxy acids using redox catalysis, act as the third reaction component which add to the unactivated alkenes. The adduct radicals engage in Giese type additions to Michael acceptors to provide, after reduction, the three-component products in an overall alkene carboamination reaction. Transformations which can be conducted under practical mild conditions feature high functional group tolerance and broad substrate scope.

| S-EPMC6900080 | biostudies-literature

Palladium Catalyzed Asymmetric Three-Component Coupling of Boronic Esters, Indoles, and Allylic Acetates.

Project description:Boronic esters react with 2-lithiated indoles to form boronate intermediates. The boronate reacts with allylic acetates in the presence of (BINAP)Pd catalysts to allylate C3 concurrent with alkyl migration from B to C2 of the indole. Overall, the process is a three-component coupling that joins an allylic acetate, and indole and an organo-B(pin) species to provide substituted indoles and indolines with high enantio-, regio-, and diastereoselectivity.

| S-EPMC5572568 | biostudies-literature

Allylboronic Esters as Acceptors in Radical Addition, Boron 1,2-Migration, and Trapping Cascades.

Project description:Radical 1,3-carboheteroarylation and 1,3-hydroalkylation of allylboronic esters comprising a 1,2-boron shift is reported. Allylboronic esters are generally used in synthesis as allylation reagents, where the boronic ester moiety gets lost. In the introduced cascades, alkylboronic esters are obtained with the boron entity remaining in the product. The carboheteroarylation of the allylboronic esters are conducted without a metal catalyst, and the 1,3-hydroalkylation is achieved using iron catalysis. Both reactions work efficiently under mild conditions.

| S-EPMC8822490 | biostudies-literature

Cu-Catalyzed Three-Component Carboamination of Alkenes.

Project description:Copper-catalyzed intermolecular carboamination of alkenes with α-halocarbonyls and amines is presented with 42 examples. Electron rich, electron poor, and internal styrenes, as well as α-olefins, are functionalized with α-halocarbonyls and aryl or aliphatic amines. Mechanistic investigations suggest the reaction is proceeding through addition of a carbon-centered radical across an olefin followed by oxidation to form a 5-membered oxocarbenium intermediate and subsequent nucleophilic ring opening to forge the C-N bond.

| S-EPMC6092015 | biostudies-literature

Oxidative Three-Component Carboamination of Vinylarenes with Alkylboronic Acids.

Project description:Three-component carboamination of alkenes is of significant interest due to the ease by which functionalized amines can be produced from readily available chemical building blocks. Previously, a variety of carbon-centered radical precursors have been studied as the carbon components for this reaction, however, the use of general alkyl sources has remained as an unsolved challenge. Herein we present our efforts to develop an oxidative carboamination protocol that utilizes alkylboronic acids as carbon-centered radical precursors. The presented work demonstrates 34 examples, ranging from 17 to 88% yields, with a broad scope in vinylarenes, amines, and alkylboronic acids. Preliminary mechanistic studies suggest that a single-electron oxidation of the alkylboronic acid generates a carbon-centered radical intermediate that adds across the olefin followed by C-N bond formation via Cu-mediated inner-sphere or carbocation-mediated pathways.

| S-EPMC9815720 | biostudies-literature

A palladium-catalyzed three-component cross-coupling of conjugated dienes or terminal alkenes with vinyl triflates and boronic acids.

Project description:A three-component coupling of vinyl triflates and boronic acids to alkenes catalyzed by palladium is reported. Using 1,3-dienes, selective 1,2-alkene difunction-alization is observed, whereas the use of terminal alkenes results in 1,1-alkene difunctionalization. The reaction outcome is attributed to the formation of stabilized, cationic Pd-π-allyl intermediates to regulate β-hydride elimination.

| S-EPMC3084658 | biostudies-literature

Stereoselective synthesis of substituted 1,3-oxazolidines via Pd-catalyzed carboamination reactions of O-vinyl-1,2-amino alcohols.

Project description:The stereoselective synthesis of 2,4- and 2,5-disubstituted 1,3-oxazolidines is accomplished via Pd-catalyzed carboamination of O-vinyl-1,2-amino alcohol derivatives. The transformations generate cis-disubstituted products with good to excellent diastereoselectivity, and enantiomerically enriched substrates are converted without loss of optical purity. In addition to yielding synthetically useful products that are difficult to generate with existing methods, these transformations illustrate that electron-rich enol ethers are viable substrates for alkene carboamination processes.

| S-EPMC3163040 | biostudies-literature