A modular synthesis of highly substituted 3-azapyrroles has been developed using a three-step sequence comprising copper-catalyzed alkyne-azide cycloaddition (CuAAC), N-H bond insertion, and cyclodehydration. 1-Sulfonyl-1,2,3-triazoles (1-STs) can be accessed from common alkyne and sulfonyl azide building blocks by CuAAC using CuTC. Rhodium(II)-acetate-promoted 1-ST denitrogenation results in highly electrophilic rhodium azavinyl carbenes that, here, underwent insertion into the N-H bond of secondary α-aminoketones to form 1,2-aminoalkenes. These products were cyclized and dehydrated using BF·OEt into highly substituted 3-azapyrroles. The three steps (CuAAC, N-H bond insertion, and cyclodehydration) could be telescoped into a one-pot process. The method proved to be highly efficient and tolerated a wide range of substituents.
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http://dx.doi.org/10.1021/acs.joc.2c00434 | DOI Listing |
Acta Crystallogr B Struct Sci Cryst Eng Mater
February 2025
Institute of Low Temperature and Structure Research, Polish Academy of Sciences, 2 Okólna, Wrocław, 50-422, Poland.
X-ray structural analysis of bis(guanidinium) disodium hypodiphosphate heptahydrate, (CHN)Na(PO)·7HO revealed close Na...
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Institut des Sciences Moléculaires, UMR CNRS 5255, Univ. Bordeaux, Talence cedex F-33405, France.
The hydration mechanism of 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA), a relevant marker of secondary organic aerosol formation from the atmospheric oxidation of α-pinene, has been investigated using the matrix-isolation infrared spectroscopy technique. The experimental results were supported by theoretical calculations. Monomers of MBTCA and heterocomplexes MBTCA-(HO) were identified.
View Article and Find Full Text PDFChemistry
January 2025
Jadavpur University, Chemistry, PG Science building, 700032, Kolkata, INDIA.
Over the past few decades, the merger of photocatalysis and transition metal-based catalysis or self-photoexcitation of transition metals has emerged as a useful tool in organic transformations. In this context, cobalt-based systems have attracted significant attention as sustainable alternatives to the widely explored platinum group heavy metals (iridium, rhodium, ruthenium) for photocatalytic chemical transformations. This review encompasses the basic types of cobalt-based homogeneous photocatalytic systems, their working principles, and the recent developments (2018-2024) in C-X (X = C, N, O, H, Si) bond formations.
View Article and Find Full Text PDFJ Org Chem
January 2025
School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou 221116, China.
1-Isochromene scaffolds are ubiquitous in natural products and significant bioactive molecules. Although several methods for these molecular syntheses have been developed, reports on the efficient construction of iminated isochromenes are still rather limited. Herein, we report a new Cu(II)-catalyzed annulation and sulfonylimination cascade of α-carbonyl-γ-alkynyl sulfoxonium ylides with sulfamides, enabling direct C-C σ-bond elimination to furnish iminated ()-1-isochromenes in 51-97% yields.
View Article and Find Full Text PDFACS Omega
January 2025
Graduate Program in Materials Science, Federal University of São Carlos-UFSCar, 18052-780 Sorocaba, São Paulo, Brazil.
The chemical functionalization of cellulose nanofibrils (CNFs) was carried out using 2-aminoethyl hydrogen sulfate as the reagent under various experimental conditions via a bimolecular nucleophilic substitution (S2) reaction. The functionalized CNFs were characterized by Fourier transform infrared spectroscopy-attenuated total reflectance. The results indicate that the chemical modification was successful, as evidenced by the presence of a band at 1540 cm, corresponding to the N-H bond of the amine group.
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