A Cu(ii)/bisoxazoline ligand-promoted formal [4 + 1] cycloaddition of diazo esters with azoalkenes formed has been developed. This strategy provides a potential protocol for the construction of dihydropyrazoles containing a quaternary center with good to excellent yields.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9059575 | PMC |
| http://dx.doi.org/10.1039/c8ra08909d | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Diastereoselective Construction of Bridged Azabicyclo[3.2.1]octane via Copper-Catalyzed Formal [4 + 3] Cycloaddition.
J Org Chem
January 2025
Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei 430030, People's Republic of China.
A novel copper-catalyzed formal diastereoselective [4 + 3] cycloaddition of 2-arylaziridines and 2-substituted cyclopentadiene was developed. This transformation provided an efficient protocol for the assembly of a highly strained bridged azabicyclo[3.2.
View Article and Find Full Text PDFVisible-Light-Induced [4 + 3]-Annulation of Carbonyl Ylides with Alkenyl Pyrazolinone for Constructing [4.2.1]-Oxo-Bridged Oxocine Skeleton.
Org Lett
January 2025
State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, P. R. China.
Herein, we present a visible-light-induced protocol for the synthesis of highly functionalized oxo-bridged oxocine skeletons. This method generates carbenes via visible-light-induced ortho-acyl diazo compounds, which are rapidly intercepted by the oxygen atom of an intermolecular acyl group to form a cyclic 1,3-dipole. The in situ generated highly reactive 1,3-dipole undergoes a facile formal [4 + 3] cycloaddition with alkenyl pyrazolinone, yielding [4.
View Article and Find Full Text PDFTransforming an azaarene into the spine of fusedbicyclics via cycloaddition-induced scaffold hopping of 5-Hydroxypyrazoles.
Nat Commun
December 2024
National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensor Technology and Health, College of Chemistry, Central China Normal University, Wuhan, P.R. China.
Skeleton editing for heteroarenes, especially pyrazoles, is challenging and remains scarce because these non-strained aromatics exhibit inert reactivities, making them relatively inactive for performing a dearomatization/cleavage sequence. Here, we disclose a cycloaddition-induced scaffold hopping of 5-hydroxypyrazoles to access the pyrazolopyridopyridazin-6-one skeleton through a single-operation protocol. By converting a five-membered aza-arene into a five-unit spine of a 6/6 fused-bicyclic, this work unlocks a ring-opening reactivity of the pyrazole core that involves a formal C = N bond cleavage while retaining the highly reactive N-N bond in the resulting product.
View Article and Find Full Text PDFRegiodivergent formal [4+2] cycloaddition of nitrosoarenes with furanyl cyclopropane derivatives as 4π components.
Chem Commun (Camb)
December 2024
Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería 8, 33006-Oviedo, Spain.
Cyclopropanes are commonly used as valuable 3-carbon building blocks. Herein, we disclose a different reactivity pattern of furanyl cyclopropanes, which serve as a 4-carbon component in Lewis acid-promoted [4+2] cycloadditions with nitrosoarenes to afford 1,2-oxazine derivatives. Importantly, the regioselectivity of the cycloaddition reaction can be controlled by the appropriate choice of the Lewis acid.
View Article and Find Full Text PDFVisible light-mediated formal alkylation and [4+1]-cycloaddition strategies of silyl enol ethers with aryldiazoacetates.
Chem Commun (Camb)
December 2024
Universidade Estadual de Campinas, Instituto de Química, CEP 13083-862, Campinas, SP, Brazil.
A reaction sequence of visible light-mediated cyclopropanation/acid-promoted ring-opening is described for the formal alkylation of silyl enol ethers with aryldiazoacetates. Under the same conditions, the Danishefsky's diene can react with aryldiazoacetates to afford [4+1]-cycloaddition adducts. Key mechanistic aspects are proposed based on experimental evidence and DFT calculations.
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!