An efficient organocatalytic enantioselective cross-aldol reaction of aryl ketones with heteroaromatic trifluoromethyl ketone hydrates enolate intermediates has been developed. The cross-aldol reactions catalyzed by Takemoto-type thiourea catalysts proceeded well under mild conditions, furnishing a variety of enantioenriched α-trifluoromethyl tertiary alcohols bearing N-heteroaromatics with good to high yields and enantioselectivities. This protocol features broad substrate scope, good functional group tolerance, and easy gram-scale preparation.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/d3ob00619k | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
On the gold(I)-catalyzed enantioselective addition of indole to diphenylallene via anion-binding catalysis.
Tetrahedron Lett
October 2024
Department of Chemistry, University of California, Berkeley, CA 94720, USA.
Neutral dual hydrogen bond donors (HBDs) are effective catalysts that enhance the electrophilicity of substrates or the Lewis/Brønsted acidity of reagents through an anion-binding mechanism. Despite their success in various enantioselective organocatalytic reactions, their application to transition metal catalysis remains rare. Herein, we report the activation of gold(I) precatalysts by chiral ureas, leading to enantioselective hydroarylation of allenes with indoles.
View Article and Find Full Text PDFCatalytic Asymmetric Desymmetrizing [4+2] Cycloaddition/Base-Mediated Oxidative Aromatization Sequence: Synthesis of Isobenzofuranone-Embedded Chiral Arenes.
Org Lett
December 2024
Department of Chemistry, Indian Institute of Technology Guwahati, North Guwahati, Assam 781039, India.
Herein, an organocatalytic asymmetric desymmetrizing [4+2] cycloaddition/base-mediated oxidative aromatization reaction sequence has been developed between spirophthalide 2,5-cyclohexadienones and β-methyl cinnamaldehydes. The reaction proceeds through chiral dienamine intermediate formation, and the densely functionalized spirocyclic isobenzofuranone-embedded chiral arenes were formed in high yields with excellent enantioselectivities. A 2-fold desymmetrization reaction was also performed, and the products were obtained in high enantioselectivities.
View Article and Find Full Text PDFAsymmetric desymmetrization of 2,5-cyclohexadienones initiated by organocatalytic conjugate addition to 4-nitro-5-styrylisoxazoles.
Chem Commun (Camb)
December 2024
Department of Chemistry, Indian Institute of Technology Jammu, Jagti, NH-44, Nagrota Bypass, Jammu 181221, J&K, India.
A highly regio-, enantio- and diastereo-selective strategy involving initial enantioselective conjugate addition to 4-nitro-5-styrylisoxazoles serves as a key step for the desymmetrization of 2,5-cyclohexadienones has been disclosed. We have designed a new class of 2,5-cyclohexadienones appended with 4-nitro-5-styrylisoxazoles to undergo organocatalytic asymmetric double or triple conjugate addition in a domino sequence depending on the substrate type leading to desymmetrization of the 2,5-cyclohexadienone core. The developed protocol allows the construction of a valuable hydrophenanthrene core or a unique bridged scaffold bearing multiple chiral centers with excellent enantio- (up to >99.
View Article and Find Full Text PDFIn-Cage Recombination Facilitates the Enantioselective Organocatalytic [1,2]-Rearrangement of Allylic Ammonium Ylides.
J Am Chem Soc
December 2024
EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St. Andrews, KY16 9ST, U.K.
The [1,2]-rearrangement of allylic ammonium ylides is traditionally observed as a competitive minor pathway alongside the thermally allowed [2,3]-sigmatropic rearrangement. Concerted [1,2]-rearrangements are formally forbidden, with these processes believed to proceed through homolytic C-N bond fission of the ylide, followed by radical-radical recombination. The challenges associated with developing a catalytic enantioselective [1,2]-rearrangement of allylic ammonium ylides therefore lie in biasing the reaction pathway to favor the [1,2]-reaction product, alongside controlling a stereoselective radical-radical recombination event.
View Article and Find Full Text PDFOrganocatalytic Enantioselective Arylation to Access Densely Aryl-Substituted P-Stereogenic Centers.
Org Lett
December 2024
Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China.
Although methods for synthesizing chiral phosphorus scaffolds are available, the potential of this molecular chirality remains largely unexplored. Herein, we present a remote desymmetrization of prochiral biaryl phosphine oxides through an organocatalytic asymmetric arylation. This metal-free approach enables the efficient synthesis of a wide range of densely functionalized P(V)-stereogenic compounds with good to excellent yields and satisfactory enantioselectivities.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!