Browse
Submit Data
Databases
API
Help

Dataset Information

38 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Efficient 1,4-addition of alpha-substituted fluoro(phenylsulfonyl)methane derivatives to alpha,beta-unsaturated compounds.

ABSTRACT: The 1,4-addition of a monofluoromethyl nucleophile to a variety of alpha,beta-unsaturated compounds has been achieved under mild conditions using either phosphines or potassium carbonate at room temperature. alpha-Substituted fluoro(phenylsulfonyl)methane easily undergoes Michael addition to alpha,beta-unsaturated ketones, esters, nitriles, sulfones, as well as propynoates at room temperature to yield the corresponding adducts in moderate to excellent yields.

SUBMITTER: Prakash GK

PROVIDER: S-EPMC2486456 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Efficient 1,4-addition of alpha-substituted fluoro(phenylsulfonyl)methane derivatives to alpha,beta-unsaturated compounds.

Prakash G K Surya GK Zhao Xiaoming X Chacko Sujith S Wang Fang F Vaghoo Habiba H Olah George A GA

Beilstein journal of organic chemistry 20080521

The 1,4-addition of a monofluoromethyl nucleophile to a variety of alpha,beta-unsaturated compounds has been achieved under mild conditions using either phosphines or potassium carbonate at room temperature. alpha-Substituted fluoro(phenylsulfonyl)methane easily undergoes Michael addition to alpha,beta-unsaturated ketones, esters, nitriles, sulfones, as well as propynoates at room temperature to yield the corresponding adducts in moderate to excellent yields. ...[more]

PMID: 18941481

Similar Datasets

Alpha-fluoro-alpha-nitro(phenylsulfonyl)methane as a fluoromethyl pronucleophile: efficient stereoselective Michael addition to chalcones.

Project description:Highly efficient stereoselective 1,4-addition of racemic alpha-fluoro-alpha-nitro(phenylsulfonyl)methane (FNSM) as a fluoromethyl pronucleophile to alpha,beta-unsaturated ketones using a wide range of chiral organobifunctional catalysts under moderate conditions in the absence of an additional base has been achieved. A series of catalysts was screened for the enantioselective addition of FNSM to chalcones and the catalysts CN I, CD I, QN I-IV, and QD I were found to enable this reaction, successfully providing exclusive 1,4-addition products stereoselectively in high yields (conversion, diastereomeric ratio, and enantiomeric excess). Studies involving a model reaction and systematic analysis of the absolute configuration support the suggested mechanism.

| S-EPMC2657402 | biostudies-literature

Organocatalytic asymmetric addition of malonates to unsaturated 1,4-diketones.

Project description:The organocatalytic Michael addition of malonates to symmetric unsaturated 1,4-diketones catalyzed by thiourea and squaramide derivatives with Cinchona alkaloids afforded the formation of a new C-C bond in high yields (up to 98%) and enantiomeric purities (up to 93%). The absolute configuration of the product was suggested from comparison of the experimental and calculated VCD spectra of the reaction product 3a.

| S-EPMC3458770 | biostudies-literature

Biocatalytic decarboxylative Michael addition for synthesis of 1,4-benzoxazinone derivatives.

Project description:The Candida antarctica lipase B (Novozym 435) is found to catalyze a novel decarboxylative Michael addition in vinylogous carbamate systems for the synthesis of 1,4-benzoxazinone derivatives. The reaction goes through Michael addition, ester hydrolysis and decarboxylation. A possible mechanism is suggested, with simultaneous lipase-catalyzed Michael addition and ester hydrolysis. The present methodology offers formation of complex products through multi-step reactions in a one pot process under mild and facile reaction conditions with moderate to high yields (51-90%) and no side product formation. The reaction seems to be is a great example of enzymatic promiscuity.

| S-EPMC9325775 | biostudies-literature

Catalytic asymmetric addition of diphenylzinc to cyclic alpha,beta-unsaturated ketones.

Project description:We have examined the use of our bis(sulfonamide) diol ligand (1) in the asymmetric addition of phenyl groups to cyclic alpha,beta-unsaturated ketones. Good to excellent enantioselectivities have been obtained with cyclic enones bearing alkyl substituents in the 2 position (71-97% enantiomeric excess). Furthermore, excellent enantioselectivities have been observed in the asymmetric phenylation of cyclic enones with 2-iodo and 2-bromo substituents. The results of this study broaden the scope of the asymmetric additions to ketones promoted by the titanium catalyst derived from ligand 1.

| S-EPMC397398 | biostudies-literature

Organocatalytic asymmetric Michael addition of unprotected 3-substituted oxindoles to 1,4-naphthoquinone.

Project description:We reported the first example of organocatalytic Michael addition of unprotected 3-prochiral oxindoles 1 to 1,4-naphthoquinone. Quinidine derivative (DHQD)(2)PYR was found to be able to catalyze this reaction in up to 83% ee, with moderate to excellent yields. This method could be used for the synthesis of enantioenriched 3,3-diaryloxindoles, and the catalytic synthesis of which was unprecedented.

| S-EPMC3458762 | biostudies-literature

Pyrrolidine catalyzed reactions of cyclopentadiene with ?,?-unsaturated carbonyl compounds: 1,2- versus 1,4-additions.

Project description:A systematic study of the reactions of cyclopentadiene with ?,?-unsaturated carbonyl compounds in the presence of catalytic pyrrolidine-H2O revealed that the reactions can either proceed with a Michael attack at the ?-carbon of enone, or 1,2-addition to the carbonyl, leadingeither to 4-cyclopentadienyl-2-butanones or 6-vinylfulvenes. The former can be isolated and/or converted to the corresponding 1,2-dihydropentalenes with base (or in one-pot at longer reaction times). Substitution pattern on the enones on the competing pathways have been studied and consistent mechanisms are proposed.

| S-EPMC4403802 | biostudies-literature

Enantioselective bifunctional iminophosphorane catalyzed sulfa-Michael addition of alkyl thiols to unactivated ?-substituted-?,?-unsaturated esters.

Project description:The highly enantioselective sulfa-Michael addition of alkyl thiols to unactivated ?-substituted-?,?-unsaturated esters catalyzed by a bifunctional iminophosphorane (BIMP) organocatalyst is described. The low acidity of the alkyl thiol pro-nucleophiles is overcome by the high Brønsted basicity of the catalyst and the chiral scaffold/thiourea hydrogen-bond donor moiety provides the required enantiofacial discrimination in the addition step. The reaction is broad in scope with respect to the alkyl thiol and ?-substituent of the ?,?-unsaturated ester, affords sulfa-Michael adducts in excellent yields (up to >99%) and enantioselectivity (up to 97?:?3 er) and can operate down to 1 mol% catalyst loading.

| S-EPMC5358540 | biostudies-literature

A Novel Family of [1,4]Thiazino[2,3,4-ij]quinolin-4-ium Derivatives: Regioselective Synthesis Based on Unsaturated Heteroatom and Heterocyclic Compounds and Antibacterial Activity.

Project description:A novel family of [1,4]thiazino[2,3,4-ij]quinolin-4-ium derivatives was synthesized by annulation reactions of 8-quinolinesulfenyl chloride with unsaturated heteroatom and heterocyclic compounds. It was found that the reactions with 4-pentenoic and 5-hexenoic acids, allyl chloride and bromide, allyl cyanate and vinyl heterocyclic compounds (N-vinyl pyrrolidin-2-one and 1-vinylimidazole) proceeded in a regioselective mode but with the opposite regiochemistry. The reactions with vinyl heterocyclic compounds included electrophilic addition of the sulfur atom of 8-quinolinesulfenyl chloride to the β-carbon atom of the vinyl group. In the case of other substrates, the annulation proceeded with the attachment of the sulfur atom to the α-carbon atom of the vinyl group. The antibacterial activity of novel water-soluble compounds against Enterococcus durans, Bacillus subtilis and Escherichia coli was evaluated. Compounds with high antibacterial activity were found.

| S-EPMC8472155 | biostudies-literature

Synthesis of α-Fluoro-α-Amino Acid Derivatives via Photoredox-Catalyzed Carbofluorination.

Project description:A mild, metal-free, regioselective carbofluorination of dehydroalanine derivatives has been developed. Alkyl radicals resulting from visible-light photoredox catalysis engage in a radical conjugate addition to dehydroalanine, with subsequent fluorination of the newly generated radical to afford an α-fluoro-α-amino acid. By using a highly oxidizing organic photocatalyst, this process incorporates non-stabilized primary, secondary, and tertiary alkyl radicals derived from commercially available alkyltrifluoroborates to furnish a wide range of fluorinated unnatural amino acids.

| S-EPMC6777868 | biostudies-literature

Oxa-Michael Addition to ?,?-Unsaturated Nitriles: An Expedient Route to ?-Amino Alcohols and Derivatives.

Project description:Water addition to ?,?-unsaturated nitriles would give facile access to the ?-hydroxy-nitriles, which in turn can be hydrogenated to the ?-amino alcohols. We have previously shown that alcohols readily add in 1,4-fashion to these substrates using Milstein's Ru(PNN) pincer complex as catalyst. However, attempted water addition to ?,?-unsaturated nitriles gave the 3-hydroxynitriles in mediocre yields. On the other hand, addition of benzyl alcohol proceeded in excellent yields for a variety of ?-substituted unsaturated nitriles. Subsequent treatment of the benzyl alcohol addition products with TMSCl/FeCl3 resulted in the formation of 3-hydroxy-alkylnitriles. The 3-benzyloxy-alkylnitriles obtained from oxa-Michael addition also could be hydrogenated directly in the presence of acid to give the amino alcohols as their HCl salts in excellent yields. Hydrogenation under neutral conditions gave a mixture of the secondary and tertiary amines. Hydrogenation in the presence of base and Boc-anhydride gave the orthogonally bis-protected amino alcohols, in which the benzyl ether can subsequently be cleaved to yield Boc-protected amino alcohols. Thus, a variety of molecular scaffolds with a 1,3-relationship between O- and N-functional group is accessible starting from oxa-Michael addition of benzyl alcohol to ?,?-unsaturated nitriles.

| S-EPMC6147005 | 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