• Title/Summary/Keyword: Tetrabutylammonium fluoride

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Development of diverse fluorides source for applicable F-18 radiofluorination method

  • Park, Su Hong;Kim, Dong Wook
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.2 no.1
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    • pp.17-21
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    • 2016
  • Alkali metal fluoride sources (MFs) such as potassium fluoride (KF) have been widely used as a fluoride source in the nucleophilic displacement reaction. However, they have low solubility and nucleophilicity in most of the organic solvents. Bulky fluoride sources such as tetrabutylammonium fluoride (TBAF) were substituted for MFs to improve these properties. However, hygroscopic property of TBAF makes it less convenient for handling as well as its strong basic property can make the side-reaction occur. Recently, novel fluoride sources have been developed to solve these problems. In this paper, we would like to introduce coordinated fluoride sources as a new fluoride sources such as tetrabutylammonium tetra(t-butyl alcohol)-coordinated fluoride, crown ether metal complex fluoride, and various bulky alcohols coordinated fluoride complexes. In particular, bulky alcohol coordinated fluoride source could generated by the controlled hydrogen-bonded of fluoride with alcohols and these fluoride sources have better stability and reactivity with showing low hygroscopic property. The study of these fluoride sources will help to understand the characteristic of [$^{18}F$]fluoride for increasing the radiochemical yield in the [$^{18}F$]radiofluorination.

Oxidation of Aromatic Aldehydes with Tetrabutylammonium Fluoride:Competition with the Cannizzaro Reaction

  • Chung, Kyoo-Hyun;Lee, Jae Hak;Chi, Dae Yoon;Moon, Byung-Chul;Lim, Choong Hwan;Kim, Jin Pil
    • Bulletin of the Korean Chemical Society
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    • v.27 no.8
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    • pp.1203-1205
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    • 2006
  • During the synthesis of 4-fluorobenzaldehyde via the SNAr reaction of 4-nitrobenzaldehyde with TBAF, it was found that an equivalent amount of TBAF could oxidize benzaldehyde to benzoic acid. The reaction of 4-nitrobenzaldehyde with tetrabutylammonium fluoride (TBAF) gave 4-nitrobenzoic acid in high yield. Depending on the reaction conditions, other aromatic aldehydes produced acids with fewer amounts of alcohols. However, this type of oxidation has limited practical applications. Nevertheless, the mechanism is quite different from the Cannizzaro reaction because the amounts of the acid salt and alcohol formed were different.

Synthesis and Characterization of Two New Fluoroplumbate(II) Complexes: Tetrabutylammonium Fluorodihaloplumbate, (But)4N[PbX2F] (X = Cl, I)

  • Javanshir, Zahra;Mehrani, Kheyrollah;Ghammamy, Shahriare;Saghatforoush, LotfAli;Seyedsadjadi, Seyedabolfazl;Hassanijoshaghani, Ali;Tavakol, Hossein
    • Bulletin of the Korean Chemical Society
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    • v.29 no.8
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    • pp.1464-1466
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    • 2008
  • Tetrabutylammonium Fluorodichloroplumbate(II), N$(C_4H_9)_4$[$PbCl_2F$], TBAFDiCP and Tetrabutylammonium Fluorodiiodoplumbate(II), [$(C_4H_9)_4$N][$PbI_2F$], TBAFDiIP are the first examples of fluoroplumbate salts that have been prepared from the reaction of $(C_4H_9)_4$NF with $PbCl_2$ and $PbI_2$ respectively using either $CH_3CN$ solvent. These new compound characterized by elemental analysis, IR, UV/Visible, $^1H$ NMR, and $^{19}F$ NMR techniques.

Syntheses of Cellulosic Graft Copolymers

  • Ikeda, Isao;Maeda, Yasushi
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.13-14
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    • 2003
  • Cellulosic graft copolymers were synthesized to use them as the functional materials. Three methods containing atom transfer radical polymerization (ATRP), macro-azo-initiator (MAI) method, and the polymerization catalyzed by tetrabutylammonium fluoride (TBAF) were performed in this work.

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Anion Sensing Properties of New Colorimetric Chemosensors Based on Thiourea and Urea Moieties

  • Kim, Dong-Wan;Kim, Jung-Hwan;Hwang, Jae-Young;Park, Jong-Keun;Kim, Jae-Sang
    • Bulletin of the Korean Chemical Society
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    • v.33 no.4
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    • pp.1159-1164
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    • 2012
  • A new colorimetric sensors containing thiourea (1-(4-nitrophenyl)-3-quinolin-6-ylthiourea; 1) and urea(1-(4-nitrophenyl)-3-quinolin-6-ylurea; 2) moieties for fluoride were designed and synthesized. These simple receptors were characterized their stoichiometry, and investigates the mechanism of their selectivity as anion receptors. The addition of tetrabutylammonium fluoride salts to the solution of receptors caused a dramatically and clearly observable color changes from colorless to yellow. To examine their application as anion receptors by UV-vis and $^1H$ NMR spectroscopy results revealed their higher selectivity for fluoride ion than other anions. The receptors and fluoride ion formed a 1:1 stoichiometry complex through strong hydrogen bonding interactions in the first step, followed by a process of deprotonation in presence of an excess of $F^-$ in DMSO solvent.

Simultaneous Observation of Fe-F and F-Fe-F Stretching Vibrations of Fluoride Anion Ligated Tetraphenylporphyrin Iron(Ⅲ) by Resonance Raman Spectroscopy

  • 이인숙;신지영;남학현;김도균;팽기정
    • Bulletin of the Korean Chemical Society
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    • v.18 no.7
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    • pp.730-733
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    • 1997
  • Monofluoroiron(Ⅲ) tetraphenylporphyrin, Fe(TPP)F, and difluoroiron(Ⅲ) tetraphenylporphyrin, [Fe(TPP)F2]- were generated in a various non-aqueous solvents by the reaction between Fe(TPP)Cl and tetrabutylammonium fluoride TBAF 3H2O. Formation of the these complexes was detected by the appearance of the ν(F-Fe) (ν, stretching vibration) at 506 cm-1 for Fe(TPP)F and the ν(F-Fe-F) at 448 cm-1 for [Fe(TPP)F2]-, simultaneously, with 441.6 nm excitation by Resonance Raman (RR) spectroscopy. These assignments were confirmed by observed frequency shifts due to 56Fe/54Fe and TPP/TPP-d8/TPP-N15 isotopic substitutions. Difluoroiron complex is an iron(Ⅲ) high-spin complex with the oxidation sensitive band at 1347 cm-1 for ν4 and core size/spin state sensitive band at 1541 cm-1 for ν2.

Synthesis of Sesquiterpene Derivitives as Potential Antitumor Agents; Elemance Derivatives

  • Choi, Bo-Gil;Kwak, Eun-Yee;Chung, Byung-Ho;Cho, Won-Jae;Cheon, Seung-Hoon
    • Archives of Pharmacal Research
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    • v.22 no.6
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    • pp.575-578
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    • 1999
  • Derivatives of elema-1,3-diene were synthesized in several steps as polar analogs of $\beta$-elemene, antitumor agent under clinical phase. The lactone ring of compound 1 was opened by LiAlH4 to give diol 2 which was selectively protected by TBDPSCI. After acetylation of the secondary alcohol, the acetylated product was ozonolyzed and reduced to give elemene derivative 4 which was converted to diolefin 8 via selenides subsequent deprotection by tetrabutylammonium fluoride gave two compounds 9, 10.

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Synthesis and Biodistribution of Flumazenil Derivative [F-18](3-(2-Fluoro) flumazenil for Imaging Benzodiazepine Receptor (벤조디아제핀 수용체 영상용 양전자 방출 핵종 표지 플루마제닐 유도체 [F-18](3-(2-Fluoro)flumazenil의 합성과 생체 내 분포)

  • Hong, Sung-Hyun;Jeong, Jae-Min;Chang, Young-Soo;Lee, Dong-Soo;Chung, June-Key;Cho, Jung-Hyuck;Lee, Sook-Ja;Kang, Sam-Sik;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.6
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    • pp.527-536
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    • 1999
  • Purpose: Radiotracers that bind to the central benzodiazepine receptor are useful for the investigation of various neurological and psychiatric diseases. [C-11]Flumazenil, a benzodiazepine antagonist, is the most widely used radioligand for central benzodiazepine receptor imaging by PET. We synthesized 3-(2-[F-18]fluoro)flumazenil, a new fluorine-18 ($t_{1/2}$= 110 min) labeled analogue of benzodiazepine receptor imaging agent, and evaluated in vivo for biodistribution in mice. Materials and Methods: Flumazenil (Ro 15-1788) was synthesized by a modification of the reported method. Precursor of 3-(2-[F-18]fluoro)flumazenil, the tosylated flumazenil derivative was prepared by the tosylation of the ethyl ester by ditosylethane. [F-18] labeling of tosyl substitued flumazenil precursor was performed by adding F-18 ion at $85^{\circ}C$ in the hot ceil for 20 min. The reaction mixture was trapped by C18 cartridge, washed with 10% ethanol, and eluted by 40% ethanol. Bidistribution in mice was determined after intravenous injection. Results: The total chemical yield of tosylated flumazenil derivative was ${\sim}40%$. The efficiency of labeling 3-(2-[F-18]fluoro)flumazenil was 66% with a total synthesis time of 50 min. Brain uptakes of 3-(2-[F-18]fluoro)flumazenil at 10, 30, 60 min after injection, were $2.5{\pm}0.37,\;2.2{\pm}0.26,\;2.1{\pm}0.11$ and blood activities were $3.7{\pm}0.43,\;3.3{\pm}0.07,\;3.3{\pm}0.09%ID/g$, respectively. Conclusion: We synthesized a tosylated flumazenil derivative which was successfully labeled with no-carrier-added F-18 by nucleophilic substitution.

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