Browse
Submit Data
Databases
API
Help

Dataset Information

26 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Intramolecular Umpolung Synthesis of Exocyclic ?-Amino Alcohols through Decarboxylative Amination.

ABSTRACT: An intramolecular aminative Umpolung cyclization strategy has been developed by using ?,?-diphenylglycine (2) as the amination and Umpolung reagent. Aldehydes (1) bearing an additional carbonyl group underwent condensation with ?,?-diphenylglycine to form an imine, decarboxylation to generate a delocalized 2-azaallylanion, and subsequent intramolecular Umpolung cyclization to produce a variety of exocyclic ?-amino alcohols (6) in 60-93% yields with up to >20:1 trans/cis selectivity under mild conditions.

SUBMITTER: Chen J

PROVIDER: S-EPMC6644024 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Intramolecular Umpolung Synthesis of Exocyclic β-Amino Alcohols through Decarboxylative Amination.

Chen Jianfeng J Tian Jiaxin J Liu Feng F Liu Yong Y Zhao Guoqing G Yuan Weicheng W Zhao Baoguo B

ACS omega 20181101 11

An intramolecular aminative Umpolung cyclization strategy has been developed by using α,α-diphenylglycine (2) as the amination and Umpolung reagent. Aldehydes (1) bearing an additional carbonyl group underwent condensation with α,α-diphenylglycine to form an imine, decarboxylation to generate a delocalized 2-azaallylanion, and subsequent intramolecular Umpolung cyclization to produce a variety of exocyclic β-amino alcohols (6) in 60-93% yields with up to >20:1 trans/cis sele ...[more]

PMID: 31458145

Similar Datasets

Enantioselective radical C-H amination for the synthesis of β-amino alcohols.

Project description:Asymmetric, radical C-H functionalizations are rare but powerful tools for solving modern synthetic challenges. Specifically, the enantio- and regioselective C-H amination of alcohols to access medicinally valuable chiral β-amino alcohols remains elusive. To solve this challenge, a radical relay chaperone strategy was designed, wherein an alcohol was transiently converted to an imidate radical that underwent intramolecular H-atom transfer (HAT). This regioselective HAT was also rendered enantioselective by harnessing energy transfer catalysis to mediate selective radical generation and interception by a chiral copper catalyst. The successful development of this multi-catalytic, asymmetric, radical C-H amination enabled broad access to chiral β-amino alcohols from a variety of alcohols containing alkyl, allyl, benzyl and propargyl C-H bonds. Mechanistic experiments revealed that triplet energy sensitization of a Cu-bound radical precursor facilitates catalyst-mediated HAT stereoselectivity, enabling the synthesis of several important classes of chiral β-amines by enantioselective, radical C-H amination.

| S-EPMC7390680 | biostudies-literature

Gold(I)-catalyzed intramolecular amination of allylic alcohols with alkylamines.

Project description:A 1:1 mixture of (1)AuCl [1 = P(t-Bu)(2)o-biphenyl] and AgSbF(6) catalyzes the intramolecular amination of allylic alcohols with alkylamines to form substituted pyrrolidine and piperidine derivatives. Gold(I)-catalyzed cyclization of (R,Z)-8-(N-benzylamino)-3-octen-2-ol (96% ee, 95% de) led to isolation of (R,E)-1-benzyl-2-(1-propenyl)piperidine in 99% yield with 96% ee, consistent with the net syn addition of the amine relative to the departing hydroxyl group.

| S-EPMC3429346 | biostudies-literature

Photocatalytic Umpolung of N- and O-substituted alkenes for the synthesis of 1,2-amino alcohols and diols.

Project description:We report an organophotocatalytic 1,2-oxyalkynylation of ene-carbamates and enol ethers using Ethynyl BenziodoXolones (EBXs). 1-Alkynyl-1,2-amino alcohols and diols were obtained in up to 89% yield. Photocatalytic formation of radical cations led to Umpolung of the innate reactivity of the alkenes, enabling addition of a nucleophilic benzoate followed by radical alkynylation.

| S-EPMC8162387 | biostudies-literature

Synthesis, Absolute Configuration, Antibacterial, and Antifungal Activities of Novel Benzofuryl β-Amino Alcohols.

Project description:A series of new benzofuryl α-azole ketones was synthesized and reduced by asymmetric transfer hydrogenation (ATH). Novel benzofuryl β-amino alcohols bearing an imidazolyl and triazolyl substituents were obtained with excellent enantioselectivity (96-99%). The absolute configuration (R) of the products was confirmed by means of electronic circular dichroism (ECD) spectroscopy supported by theoretical calculations. Selected benzofuryl α-azole ketones were also successfully asymmetrically bioreduced by fungi of Saccharomyces cerevisiae and Aureobasidium pullulans species. Racemic and chiral β-amino alcohols, as well as benzofuryl α-amino and α-bromo ketones were evaluated for their antibacterial and antifungal activities. From among the synthesized β-amino alcohols, the highest antimicrobial activity was found for (R)-1-(3,5-dimethylbenzofuran-2-yl)-2-(1H-imidazol-1-yl)ethan-1-ol against S. aureus ATCC 25923 (MIC = 64, MBC = 96 μg mL-1) and (R)-1-(3,5-dimethylbenzofuran-2-yl)-2-(1H-1,2,4-triazol-1-yl)ethan-1-ol against yeasts of M. furfur DSM 6170 (MIC = MBC = 64 μg mL-1). In turn, from among the tested ketones, 1-(benzofuran-2-yl)-2-bromoethanones (1-4) were found to be the most active against M. furfur DSM 6170 (MIC = MBC = 1.5 μg mL-1) (MIC-minimal inhibitory concentration, MBC-minimal biocidal concentration).

| S-EPMC7560283 | biostudies-literature

The inverted ketene synthon: a double umpolung approach to enantioselective β2,3-amino amide synthesis.

Project description:A stereocontrolled synthesis of β2,3-amino amides is reported. Innovation is encapsulated by the first use of nitroalkenes to achieve double umpolung in enantioselective β-amino amide synthesis. Step economy is also fulfilled by the use of Umpolung Amide Synthesis (UmAS) in the second step, delivering the amide product without intermediacy of a carboxylic acid or activated derivative. Molybdenum oxide-mediated hydride reduction provides the anti-β2,3-amino amide with high selectivity.

| S-EPMC6349014 | biostudies-literature

An Umpolung Strategy for the Synthesis of ?-Aminoketones via Copper-Catalyzed Electrophilic Amination of Cyclopropanols.

Project description:A novel copper-catalyzed electrophilic amination of cyclopropanols with O-benzoyl-N,N-dialkylhydroxylamines to synthesize various ?-aminoketones via a sequence that includes C-C bond cleavage and Csp(3)-N bond formation is reported. The reaction conditions are mild and tolerate a wide range of functional groups including benzoate, tosylate, expoxide, and ?,?-unsaturated carbonyls, which are incompatible in the traditional amine nucleophilic conjugate addition and the Mannich reaction conditions. Preliminary mechanistic studies and a proposed catalytic cycle of this umpolung ?-aminoketone synthesis process have been described as well.

| S-EPMC4690534 | biostudies-literature

Intramolecular asymmetric reductive amination: synthesis of enantioenriched dibenz[c,e]azepines.

Project description:An Ir-catalyzed intramolecular asymmetric reductive amination (ARA) of bridged biaryl derivatives has been described. Using this unprecedented approach, synthetically useful dibenz[c,e]azepines containing both central and axial chiralities are obtained with excellent enantiocontrol (up to 97% ee). This methodology represents a rare example of enantioselective chemocatalytic synthesis of chiral dibenz[c,e]azepines featuring a broad substrate scope, and their synthetic utilities are exhibited by derivatizing the products into a chiral amino acid derivative and chiral phosphoramidite ligands, which display excellent enantiocontrol in Rh-catalyzed asymmetric hydrogenation of α-dehydroamino acid derivatives. Remarkably, our method is also applicable to enantioselectively synthesize an allocolchicine analogue.

| S-EPMC6385856 | biostudies-other

Stereoselective synthesis of β-hydroxy enamines, aminocyclopropanes, and 1,3-amino alcohols via asymmetric catalysis.

Project description:Tandem methods for the catalytic asymmetric preparation of enantioenriched β-hydroxy (E)-enamines and aminocyclopropanes are presented. The diastereoselective hydrogenation of enantioenriched (E)-trisubstituted hydroxy enamines to generate 1,2-disubstituted-1,3-amino alcohols is also outlined. These methods are initiated by highly regioselective hydroboration of N-tosyl-substituted ynamides with diethylborane to generate β-amino alkenyl boranes. In situ boron-to-zinc transmetalation generates β-amino alkenylzinc reagents. These functionalized vinylzinc intermediates are subsequently added to aldehydes in the presence of a catalyst derived from an enantioenriched amino alcohol (morpholino isoborneol, MIB). The catalyst promotes highly enantioselective C-C bond formation to provide β-hydroxy enamines in good isolated yields (68-86%) with 54-98% enantioselectivity. The intermediate zinc β-alkoxy enamines can be subjected to a tandem cyclopropanation to afford aminocyclopropyl carbinols with three continuous stereocenters in a one-pot procedure with good yields (72-82%), enantioselectivities of 76-94%, and >20:1 diastereomeric ratios. Diastereoselective hydrogenation of isolated enantioenriched β-hydroxy enamines over Pd/C furnished syn-1,2-disubstituted-1,3-amino alcohols in high yields (82-90%) with moderate to excellent diastereoselectivities. These methods were used in an efficient preparation of the enantioenriched precursor to PRC200-SS derivatives, which are potent serotonin-norepinephrine-dopamine reuptake inhibitors.

| S-EPMC3014220 | biostudies-literature

Catalytic Asymmetric Synthesis of Trifluoromethylated ?-Amino Acids through the Umpolung Addition of Trifluoromethyl Imines to Carboxylic Acid Derivatives.

Project description:Novel cinchona alkaloid derived chiral phase-transfer catalysts enabled the highly chemo-, regio-, diastereo-, and enantioselective umpolung addition of trifluoromethyl imines to ?,?-unsaturated N-acyl pyrroles. With a catalyst loading ranging from 0.2 to 5.0?mol?%, this new catalytic asymmetric transformation provides facile and high-yielding access to highly enantiomerically enriched chiral trifluoromethylated ?-amino acids and ?-lactams.

| S-EPMC6408948 | biostudies-literature

Catalytic Asymmetric Synthesis of Chiral ?-Amino Ketones via Umpolung Reactions of Imines.

Project description:The first direct catalytic asymmetric synthesis of ?-amino ketones was realized by the development of a highly diastereoselective and enantioselective C-C bond-forming umpolung reaction of imines and enones under the catalysis of a new cinchona alkaloid-derived phase-transfer catalyst. In a loading ranging from 0.02 to 2.5 mol %, the catalyst activates a broad range of trifluoromethyl imines and aldimines as nucleophiles to engage in chemo-, regio-, diastereo- and enantioselective C-C bond-forming reactions with acyclic and cyclic enones, thereby converting these readily available prochiral starting materials into highly enantiomerically enriched chiral ?-amino ketones in synthetically useful yields. Enabled by this unprecedented umpolung reaction of imines, conceptually new and concise routes were developed for the asymmetric synthesis of nitrogen-heterocycles such as pyrrolidines and indolizidines.

| S-EPMC5654742 | 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