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An efficient and cost-effective ruthenium-catalyzed oxidative cyclization of phosphonic acid monoesters or phosphinic acids with alkynes has been developed for the synthesis of a wide range of phosphaisocoumarins in good to excellent yields under aerobic conditions. A multitude of arylphosphonic acid monoesters and arylphosphinic acids having electron-donating and -withdrawing groups were oxidatively cyclized. Various diarylacetylenes, dialkylacetylenes, and alkylarylacetylenes effectively underwent the ruthenium-catalyzed oxidative cyclization. A substrate possessing benzoic acid as well as a phenylphosphonic monoester moiety was smoothly cyclized with hex-3-yne to afford a compound having both isocoumarin and phosphaisocoumarin moieties. Alkenylphosphonic monoester afforded phosphorus 2-pyrone through oxidative cyclization with alkyne. Competition experiments between diaryl- and dialkylalkynes and between diarylacetylenes having p-methoxy and p-chloro groups gave results which showed that the present oxidative cyclizations were not affected by the electronic effects of alkynes. Mechanistic studies revealed C-H bond metalation to be the rate-limiting step.
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http://dx.doi.org/10.1021/jo401608v | DOI Listing |
Angew Chem Int Ed Engl
September 2025
Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry, LIFM, IGCME, GBRCE for Functional Molecular Engineering, Sun Yat-Sen University, Guangzhou, 510006, China.
Oximes serve as indispensable intermediates in synthetic chemistry, owing to their distinctive C═N─OH structure, conferring highly versatile reactivity. Synthesis of oxime via the electrochemical method has potential advantages, accompanied by the upgrading of industrialization. Herein, we propose a novel strategy by introducing nickel (Ni) mediation to obtain high-spin iron (Fe)(III) in phthalocyanine structure for synthesizing glyoxylate oxime via electrocatalytic nitric oxide (NO) coupling with keto acid.
View Article and Find Full Text PDFOrg Biomol Chem
September 2025
Research Centre of Modern Analytical Technology, Tianjin University of Science & Technology, Tianjin 300457, China.
A tetrahydroxydiboron-mediated radical cyclization of unactivated alkenes under photoinduced reaction conditions was developed to synthesize ring-fused quinazolinones for the first time. The concise, mild and photocatalyst- and oxidant-free conditions, as well as the good functional group tolerance, render this protocol a green and convenient strategy for synthesizing polycyclic ring-fused quinazolinones. Mechanistic studies indicated that the process might involve a radical pathway.
View Article and Find Full Text PDFPhotochem Photobiol Sci
September 2025
Faculity of Engineering, Yokohama National University, 79-5, Tokiwadai, Hodogaya, Yokohama, Kanagawa, 240-8501, Japan.
In recent years, fluorescence-switchable molecules have garnered significant attention as fluorescent dyes for super-resolution fluorescence microscopy, which is increasingly demanded in the field of biochemical imaging. Among such molecules, diarylethene-S,S,S',S'-tetraoxide derivatives have proven particularly promising due to their ability to achieve high contrast fluorescence switching. Diarylethenes incorporating perfluorocyclopentene as the ethene bridge have become the standard scaffold due to their excellent fatigue resistance and thermal stability.
View Article and Find Full Text PDFJ Org Chem
September 2025
Yunnan Key Laboratory of Modern Separation Analysis and Substance Transformation, College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming, Yunnan Province 650500, P. R. China.
Photoinduced trifluoroethyl and acyl radical procedures for the efficient and simple preparation of iodotrifluoroethylated and acylated pyrrolidine-2-ones from -tethered 1,6-enynes with 1,1,1-trifluoro-2-iodoethane and acyl oxime esters are reported. The photoinduced iodotrifluoroethylation is performed via the energy transfer (EnT) process of the fluorescein sodium-mediated atom-transfer radical addition (ATRA) strategy under visible-light irradiation. The acylation is carried out with 4CzIPN as an organophotocatalyst at room temperature under metal- and oxidant-free conditions.
View Article and Find Full Text PDFNat Chem
September 2025
Laboratorium für Organische Chemie, ETH Zürich, Zurich, Switzerland.
The ability to selectively edit organic molecules at the atomic level has the potential to streamline lead discovery and optimization in the pharmaceutical and agrochemical industry. While numerous atom insertion and deletion reactions have recently been reported, examples of single atom swaps remain scarce due to the challenge of orchestrating the selective cleavage and formation of multiple chemical bonds around the same atom. Here we report a method for the carbon-to-nitrogen atom swap in N-alkyl indoles, allowing the direct conversion of indoles to the corresponding benzimidazoles.
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