24401-39-6Relevant academic research and scientific papers
Metal-Free Oxidative Decarbonylative [3+2] Annulation of Terminal Alkynes with Tertiary Alkyl Aldehydes toward Cyclopentenes
Zou, Hua-Xu,Li, Yang,Yang, Xu-Heng,Xiang, Jiannan,Li, Jin-Heng
, p. 8581 - 8588 (2018)
A new metal-free oxidative decarbonylative [3+2] annulation of terminal alkynes with tertiary alkyl aldehydes is presented, which features broad substrate scope and excellent selectivity. The selectivity of this reaction toward cyclopentenes and indenes relies on the nature of the aldehyde substrates. While treatment of tertiary γ,δ-unsaturated aldehydes with common terminal alkynes assembles cyclopentenes, 2-methyl-2-arylpropanals succeed in accessing indenes.
Rhodium-Catalyzed Tandem Isomerization-Allylation: From Diallyl Carbonates to α-Quaternary Aldehydes
Masson-Makdissi, Jeanne,Jang, Young Jin,Prieto, Liher,Taylor, Mark S.,Lautens, Mark
, p. 11808 - 11812 (2019/12/02)
We report a Rh-catalyzed tandem isomerization-allylation sequence for the generation of α-quaternary aldehydes, starting from unsymmetrical diallyl carbonates. This reaction features a highly selective oxidative addition of the rhodium catalyst, leading to the discrimination of electrophilic and nucleophilic elements of various diallyl carbonates. A rhodium-enolate and an allyl electrophile are produced catalytically in situ in a controlled fashion, enabling this reaction to occur with high chemoselectivity and regioselectivity. Mechanistic investigation via reaction progress kinetic analysis uncovered second-order kinetics in rhodium, suggesting that an unexpected dual metal pathway may be operative for the key C-C bond-forming step.
Nickel-Catalyzed α-Allylation of Aldehydes and Tandem Aldol Condensation/Allylation Reaction with Allylic Alcohols
Bernhard, Yann,Thomson, Brodie,Ferey, Vincent,Sauthier, Mathieu
supporting information, p. 7460 - 7464 (2017/06/13)
An additive-free nickel-catalyzed α-allylation of aldehydes with allyl alcohol is reported. The reaction is promoted by 1 mol % of in situ formed nickel complex in methanol, and water is the sole by-product of the reaction. The experimental conditions allow the conversion of various α-branched aldehydes and α,β-unsaturated aldehydes as nucleophiles. The same catalyst and reaction conditions enabled a tandem aldol condensation of aldehyde/α-allylation reaction.
Isomerization of olefins triggered by rhodium-catalyzed C-H bond activation: Control of endocyclic β-hydrogen elimination
Yip, Stephanie Y. Y.,A?ssa, Christophe
, p. 6870 - 6873 (2015/06/02)
Five-membered metallacycles are typically reluctant to undergo endocyclic β-hydrogen elimination. The rhodium-catalyzed isomerization of 4-pentenals into 3-pentenals occurs through this elementary step and cleavage of two C-H bonds, as supported by deuterium-labeling studies. The reaction proceeds without decarbonylation, leads to trans olefins exclusively, and tolerates other olefins normally prone to isomerization. Endocyclic β-hydrogen elimination can also be controlled in an enantiodivergent reaction on a racemic mixture.
Activation of alcohols with carbon dioxide: Intermolecular allylation of weakly acidic pronucleophiles
Lang, Simon B.,Locascio, Theresa M.,Tunge, Jon A.
supporting information, p. 4308 - 4311 (2014/11/08)
The direct coupling of allyl alcohols with nitroalkanes, nitriles, and aldehydes using catalytic Pd(PPh3)4 has been accomplished via activation of C-OH bonds with CO2. The in situ formation of carbonates from alcohols and CO2 facilitates oxidative addition to Pd to form reactive π-allylpalladium intermediates. In addition, the formation of a strong base activates nucleophiles toward the reaction with the π-allylpalladium electrophile. Overall, this atom economical reaction provides a new C-C bond without the use of an external base and generates water as the only byproduct.
Asymmetric α-allylation of α-branched aldehydes with allyl alcohols by synergistic catalysis using an achiral palladium complex and a chiral primary amino acid
Yoshida, Masanori,Masaki, Erika,Terumine, Tatsuaki,Hara, Shoji
, p. 1367 - 1373 (2014/06/09)
Highly enantioselective direct α-allylation of α-branched aldehydes with simple allyl alcohols was achieved by the combined use of an achiral transition-metal catalysis with a palladium complex and a chiral organocatalysis with a readily obtainable primary α-amino acid. Various α-allylated aldehydes possessing a stereocontrolled quaternary carbon stereogenic center were synthesized in high yields with high enantioselectivity. Georg Thieme Verlag Stuttgart New York.
Palladium/Bronsted acid-catalyzed α-allylation of aldehydes with allylic alcohols
Jiang, Gaoxi,List, Benjamin
experimental part, p. 1667 - 1670 (2011/09/14)
A simple, highly efficient, and readily scalable direct α-allylation of aldehydes with allylic alcohols that is co-catalyzed by palladium and a Bronsted acid has been developed. Copyright
Pd-catalyzed α-allylation of 2-phenylpropanal and other carbonyl compounds with allyl alcohol and allyl acetates/carbonates in ionic liquids
Hut'Ka, Martin,Toma, Stefan
, p. 1175 - 1179 (2008/03/27)
The successful Pd-catalysed allylation of 2-phenylpropanal with allyl alcohol in ionic liquid is described and thus a simplier reaction composition catalytic system than in THF is possible. On the other hand, the Pd-catalyzed α-allylation of the same substrate with allyl acetate or allyl ethyl carbonate is proceeding nicely in ionic liquids. Allylation of different carbonyl derivatives was studied and it was found that the reaction is restricted to carbonyl derivatives from which a carbanion stabilized by an adjacent aromatic ring can be formed.
1,1,1-TRIFLUORO-4-PHENYL-4-METHYL-2-(1H-PYRROLO
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Page/Page column 211, (2010/02/11)
Compounds of Formula (IA), IB), IC), and (ID) wherein R1, R2, R3, R4, R5, and R6 are as respectively defined herein for Formula (IA), (IB), (IC), and (ID), or a tautomer, prodrug, solvate, or salt thereof; pharmaceutical compositions containing such compounds, and methods of modulating the glucocorticoid receptor function and methods of treating disease-states or conditions mediated by the glucocorticoid receptor function or characterized by inflammatory, allergic, or proliferative processes in a patient using these compounds.
Chemokine receptor binding heterocyclic compounds with enhanced efficacy
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, (2008/06/13)
The invention relates to heterocyclic compounds consisting of a core nitrogen atom surrounded by three pendant groups, wherein two of the three pendant groups are preferably benzimidazolyl methyl and tetrahydroquinolyl, and the third pendant group contains N and optionally contains additional rings. The compounds bind to chemokine receptors, including CXCR4 and CCR5, and demonstrate protective effects against infection of target cells by a human immunodeficiency virus (HIV).
