The axial-equatorial conformational isomer distribution of the reactant diazoacetoacetate or its metal carbene intermediate is reflected in Rh(II) catalyzed oxonium ylide forming reactions of 3-(trans-2-arylvinyl)tetrahydropyranone-5-diazoacetoacetates that afford diastereoisomeric products for both the symmetry-allowed [2,3]- and the formally symmetry-forbidden [1,2]-oxonium ylide rearrangements.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3321102 | PMC |
| http://dx.doi.org/10.1021/ol300213u | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Carbodefluorination of fluoroalkyl ketones via a carbene-initiated rearrangement strategy.
Nat Commun
July 2022
Department of Chemistry, Northeast Normal University, Changchun, 130024, China.
The C-F bond cleavage and C-C bond formation (i.e., carbodefluorination) of readily accessible (per)fluoroalkyl groups constitutes an atom-economical and efficient route to partially fluorinated compounds.
View Article and Find Full Text PDFConvergent Synthesis of the C1-C29 Framework of Amphidinolide F.
J Org Chem
June 2022
School of Chemistry, University of Glasgow, Joseph Black Building, University Avenue, Glasgow G12 8QQ, U.K.
The complete carbon framework of the macrocyclic marine natural product amphidinolide F has been prepared by a convergent synthetic route in which three fragments of similar size and complexity have been coupled. Key features of the syntheses of the fragments include the stereoselective construction of the tetrahydrofuran in the C1-C9 fragment by oxonium ylide (free or metal-bound) formation and rearrangement triggered by the direct generation of a rhodium carbenoid from 1-sulfonyl-1,2,3-triazole, the highly diastereoselective aldol reaction between a boron enolate and an aldehyde with 1,4-control to prepare the C10-C17 fragment, and the formation of the tetrahydrofuran in the C18-C29 fragment by intramolecular nucleophilic ring opening of an epoxide with a hydroxyl group under acidic conditions.
View Article and Find Full Text PDFCatalytic rearrangements of onium ylides in aromatic systems.
Org Biomol Chem
May 2022
Department of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, USA.
Onium ylides are reactive intermediates that undergo versatile chemical transformations to give structurally interesting compounds. Rearrangement reactions of onium ylides are of great importance to synthetic organic chemists, as they provide efficient methods for C-C bond formations as well as installation of new stereogenic centers in molecules. Traditionally, onium ylides have been shown to undergo two types of rearrangements, namely, [2,3]- and [1,2]-rearrangements.
View Article and Find Full Text PDFCatalyst-Controlled Regiodivergence in Rearrangements of Indole-Based Onium Ylides.
J Am Chem Soc
June 2021
Department of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, United States.
We have developed catalyst-controlled regiodivergent rearrangements of onium-ylides derived from indole substrates. Oxonium ylides formed from substituted indoles selectively undergo [2,3]- and [1,2]-rearrangements in the presence of a rhodium and a copper catalyst, respectively. The combined experimental and density functional theory (DFT) computational studies indicate divergent mechanistic pathways involving a metal-free ylide in the rhodium catalyzed reaction favoring [2,3]-rearrangement, and a metal-coordinated ion-pair in the copper catalyzed [1,2]-rearrangement that recombines in the solvent-cage.
View Article and Find Full Text PDFRh(II)-Catalyzed Spirocyclization of α-Diazo Homophthalimides with Cyclic Ethers.
J Org Chem
April 2019
Saint Petersburg State University, Saint Petersburg 199034 , Russian Federation.
Rh(II)-catalyzed decomposition of α-diazo homophthalimides in the presence of cyclic ethers gave spirocyclic products of Stevens-type [1,2]-alkyl shift within the postulated oxonium ylide intermediate. Such a reaction pathway is in line with thermodynamic predictions obtained from quantum chemical calculations performed at the B3LYP/6-31G* and B3LYP/6-311++G** levels of theory. These findings represent the first systematically investigated case of spirocyclization of cyclic α-diazocarbonyl compounds with cyclic ethers.
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!