• Title/Summary/Keyword: Hypervalent

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[18F]Aryl fluorides from hypervalent iodine compounds

  • Chun, Joong-Hyun;Son, Jeongmin;Park, Jun Young;Yun, Mijin
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.3 no.1
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    • pp.3-14
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    • 2017

  • Nucleophilic aromatic fluorination has been one of the most explored methods in fluorin-18 based radiochemistry. Unlike electrophilic $[^{18}F]$fluorination methods, no-carrier-added nucleophilic radiofluorination with cyclotron-produced $[^{18}F]$fluoride ion offers better specific radioactivity which is essential aspect to obtain good quality images from positron emission tomography. Contrary to amenable aliphatic radiofluorination, the development of reliable aromatic $[^{18}F]$fluorination methods has been pursued by many research groups; however, no viable method has yet been established. Recently, hypervalent iodine compound draws increasing attention as versatile radiolabeling precursor for various $[^{18}F]$fluoroarenes, since it bears the capacity to introduce fluorine-18 either on electron-deficient or electron-rich aryl ring with enhanced regiospecificity. Other classes of hypervalent iodine congeners often utilized in radiochemistry are iodylarenes, iodonium ylides, and spirocyclic iodonium ylides. Recently developed spirocyclic iodonium ylides have already been avidly employed to provide various $[^{18}F]$aryl fluorides with high labeling efficiency. This metal-free protocol would afford efficient routes, replacing the traditional approaches to $[^{18}F]$fluoroarenes, from prosthetic labeling synthons to complex PET radiotracers.

  • https://doi.org/10.22643/JRMP.2017.3.1.3 인용 PDF KSCI

Mechanistic Investigation of the Copper(I)-Catalyzed Trifluoromethylthiolation Using Sulfonyl Hypervalent Iodonium Ylide as the SCF3 Source: A DFT Study

  • Park, Yoonsu;Jung, Yousung
    • Proceeding of EDISON Challenge
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    • 2014.03a
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    • pp.337-346
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    • 2014

  • Trifluoromethylthiol functional group(이하 -SCF3)은 약학적으로 유용한 물질이다. 이 연구는 최근 개발된 Shibata의 Direct trifluoromethylthiolation reaction의 반응 메커니즘을 계산화학적으로 평가했다. 반응 메커니즘은 크게 Carbene formation, Rearrangement, Electrophilic SCF3 reagent generation 세 단계로 나눌 수 있다. 각 과정에 대해 구조에 대한 full optimization이 진행되었고, 특히 alpha-carbene sulfonyl species의 thermal rearrangement에 관한 첫번째 계산화학적 평가가 이루어졌다.

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Acid and Nucleophile Catalysed Hydrolyses of Benzenesulfinamides (벤젠술핀아미드의 가수분해반응에서 산 및 할라이드 이온의 촉매작용)

  • Lee, Jong-Pal;Cho, Young-Su
    • Journal of Life Science
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    • v.20 no.12
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    • pp.1906-1909
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    • 2010

  • Acid and halide ion catalyses for the hydrolysis of benzenesulfinamides were kinetically investigated. The rates of hydrolysis increased with increasing concentration of both acid and halide ions and also showed to speed up as the electron donating ability of the benzenesulfinyl moiety and the electron withdrawing ability in the leaving group increased. The reactivity of halide ions was in the order of $Br^-$ > $Cl^-$. The reaction mechanism may be accommodated by including a hypervalent intermediate and sulfonium cation.

  • https://doi.org/10.5352/JLS.2010.20.12.1906 인용 PDF KSCI