- Optimization and synthesis of an 18F-labeled dopamine D3 receptor ligand using [18F]fluorophenylazocarboxylic tert-butylester
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There is still no efficient fluorine-18-labeled dopamine D3 subtype selective receptor ligand for studies with positron emission tomography. We aim at improving the D3 selectivity and hydrophilicity of a candidate ligand by changing the substitution pattern to a 2,3-dichlorophenylpiperazine and hydroxylation of the butyl chain. The compound [18F]3 exhibited D3 affinity of Ki = 3.6 nM, increased subtype selectivity (Ki(D2/D3) = 60), and low affinity to 5-HT1A and α1 receptors (Ki (5-HT1A/D3) = 34; Ki (α1/D3) = 100). The two-step radiosynthesis was optimized for analog [18F]4 by reducing the necessary concentration of the precursor amine (57 mM), which reacted with [18F]fluorophenylazocarboxylic tert-butylester under basic conditions. The optimization of the base (Cs 2CO3, 23 mM) and the adjustment of reaction temperature led to the radiochemical yield of 63% after 5 min at 35C. The optimized reaction conditions were transferred on to the synthesis of [18F]3 with an overall non-decay corrected yield of 8-12% in a specific activity of 32-102 GBq/μmol after a total synthesis time of 30-35 min. This provides a D 3 radioligand candidate with improved attributes concerning selectivity and radiosynthesis for further preclinical studies.
- Nebel, Natascha,Maschauer, Simone,Hocke, Carsten,Hübner, Harald,Gmeiner, Peter,Prante, Olaf
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Read Online
- Exploration of alcohol-enhanced Cu-mediated radiofluorination toward practical labeling
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Copper-mediated nucleophilic radiofluorination using boronic precursors is a promising, general method to label aromatic compounds with [18F]fluoride. However, in various reports, large amounts of precursor (60 μmol) were needed to achieve high
- Zhou, Dong,Chu, Wenhua,Katzenellenbogen, John A.
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- Chemoselective Radiosyntheses of Electron-Rich [18F]Fluoroarenes from Aryl(2,4,6-trimethoxyphenyl)iodonium Tosylates
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Hypervalent diaryliodonium salts have been used to produce various [18F]fluoroarenes. The iodonium salt approach as a labeling precursor has been established to equally afford complex 18F-fluorinated molecules. Because of the inheren
- Kwon, Young-Do,Son, Jeongmin,Chun, Joong-Hyun
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p. 3678 - 3686
(2019/03/11)
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- Ring-Closing Synthesis of Dibenzothiophene Sulfonium Salts and Their Use as Leaving Groups for Aromatic 18F-Fluorination
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Herein, we report a novel intramolecular ring-closing reaction of biaryl thioethers that give access to highly functionalized dibenzothiophene sulfonium salts under mild conditions. The resulting precursors react regioselectively with [18F]fluo
- Gendron, Thibault,Sander, Kerstin,Cybulska, Klaudia,Benhamou, Laure,Sin, Pak Kwan Brian,Khan, Aqsa,Wood, Michael,Porter, Michael J.,?rstad, Erik
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p. 11125 - 11132
(2018/09/11)
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- Alcohol-Enhanced Cu-Mediated Radiofluorination
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The potential of many 18F-labeled (hetero)aromatics for applications in positron emission tomography remains underexplored because convenient procedures for their radiosynthesis are lacking. Consequently, simple methods to prepare radiofluorinated (hetero)arenes are highly sought after. Herein, we report the beneficial effect of primary and secondary alcohols on Cu-mediated 18F-labeling. This observation contradicts the assumption that such alcohols are inappropriate solvents for aromatic fluorination. Therefore, we developed a protocol for rapid radiolabeling of an extraordinarily broad scope of boronic and stannyl substrates under general reaction conditions. Notably, radiofluorinated indoles, phenols, and anilines were synthesized directly from the corresponding unprotected precursors. Furthermore, the novel method enabled the preparation of radiofluorinated tryptophans, [18F]F-DPA, [18F]DAA1106, 6-[18F]FDA, and 6-[18F]FDOPA.
- Zischler, Johannes,Kolks, Niklas,Modemann, Daniel,Neumaier, Bernd,Zlatopolskiy, Boris D.
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supporting information
p. 3251 - 3256
(2017/03/17)
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- A practical method for the preparation of 18F-labeled aromatic amino acids from nucleophilic [18F]fluoride and stannyl precursors for electrophilic radiohalogenation
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In a recent contribution of Scott et al., the substrate scope of Cu-mediated nucleophilic radiofluorination with [18F]KF for the preparation of 18F-labeled arenes was extended to aryland vinylstannanes. Based on these findings, the potential of this reaction for the production of clinically relevant positron emission tomography (PET) tracers was investigated. To this end, Cu-mediated radiofluorodestannylation using trimethyl(phenyl)tin as a model substrate was re-evaluated with respect to different reaction parameters. The resulting labeling protocol was applied for 18F-fluorination of different electron-rich, -neutral and -poor arylstannyl substrates in RCCs of 16-88%. Furthermore, this method was utilized for the synthesis of 18F-labeled aromatic amino acids from additionally N-Boc protected commercially available stannyl precursors routinely applied for electrophilic radiohalogenation. Finally, an automated synthesis of 6-[18F]fluoro-L-m-tyrosine (6-[18F]FMT), 2-[18F]fluoro-L-tyrosine (2-[18F]F-Tyr), 6-[18F]fluoro-L-3, 4-dihydroxyphenylalanine (6-[18F]FDOPA) and 3-O-methyl-6-[18F]FDOPA ([18F]OMFD) was established furnishing these PET probes in isolated radiochemical yields (RCYs) of 32-54% on a preparative scale. Remarkably, the automated radiosynthesis of 6-[18F]FDOPA afforded an exceptionally high RCY of 54 5% (n = 5).
- Zarrad, Fadi,Zlatopolskiy, Boris D.,Krapf, Philipp,Zischler, Johannes,Neumaier, Bernd
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supporting information
(2018/01/17)
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- Crystal Structures of Diaryliodonium Fluorides and Their Implications for Fluorination Mechanisms
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The radiofluorination of diaryliodonium salts is of value for producing radiotracers for positron emission tomography. We report crystal structures for two diaryliodonium fluorides. Whereas diphenyliodonium fluoride (1 a) exists as a tetramer bridged by four fluoride ions, 2-methylphenyl(phenyl)iodonium fluoride (2 a) forms a fluoride-bridged dimer that is further halogen bonded to two other monomers. We discuss the topological relationships between the two and their implications for fluorination in solution. Both radiofluorination and NMR spectroscopy show that thermolysis of 2 a gives 2-fluorotoluene and fluorobenzene in a 2 to 1 ratio that is in good agreement with the ratio observed from the radiofluorination of 2-methylphenyl(phenyl)iodonium chloride (2 b). The constancy of the product ratio affirms that the fluorinations occur via the same two rapidly interconverting transition states whose energy difference dictates chemoselectivity. From quantum chemical studies with density functional theory we attribute the “ortho-effect” to the favorable electrostatic interaction between the incoming fluoride and the o-methyl in the transition state. By utilizing the crystal structures of 1 a and 2 a, the mechanisms of fluoroarene formation from diaryliodonium fluorides in their monomeric, homodimeric, heterodimeric, and tetrameric states were also investigated. We propose that oligomerization energy dictates whether the fluorination occurs through a monomeric or an oligomeric pathway.
- Lee, Yong-Sok,Chun, Joong-Hyun,Hodo??ek, Milan,Pike, Victor W.
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supporting information
p. 4353 - 4363
(2017/04/03)
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- An Investigation of (Diacetoxyiodo)arenes as Precursors for Preparing No-Carrier-Added [18F]Fluoroarenes from Cyclotron-Produced [18F]Fluoride Ion
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Treatment of (diacetoxyiodo)arenes (1a-1u) with cyclotron-produced [18F]fluoride ion rapidly affords no-carrier-added [18F]fluoroarenes (2a-2u) in useful yields and constitutes a new method for converting substituted iodoarenes into substituted [18F]fluoroarenes in just two steps.
- Haskali, Mohammad B.,Telu, Sanjay,Lee, Yong-Sok,Morse, Cheryl L.,Lu, Shuiyu,Pike, Victor W.
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p. 297 - 302
(2016/01/15)
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- METAL OXIDE CATALYZED RADIOFLUORINATION
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Inter alia, the first titania-catalyzed [18F]-radiofluorination in highly aqueous medium is provided. In embodiments, the method utilizes titanium dioxide, 1 : 1 acetonitrile- thexyl alcohol solvent mixture and tetrabutylammonium bicarbonate as a base. Radiolabeling may be directly performed with aqueous [18F]fluoride without the need for drying/azeotroping step, which reduces radiosynthesis time while keeping high fluoride conversion. The general applicability of the synthetic strategy to the synthesis of the wide range of PET probes from tosylated precursors is demonstrated.
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- Solid-Supported Iodonium Salts for Fluorinations
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Solid-supported iodonium salt precursors have been prepared and used for the production of fluoroarenes. The importance of the resin functionality for the attachment of the iodonium salt moieties has been demonstrated. Furthermore, the production of new i
- Edwards, Richard,De Vries, Wilke,Westwell, Andrew D.,Daniels, Stephen,Wirth, Thomas
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supporting information
p. 6909 - 6916
(2015/11/02)
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- Copper-mediated aromatic radiofluorination revisited: Efficient production of PET tracers on a preparative scale
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Two novel methods for copper-mediated aromatic nucleophilic radiofluorination were recently reported. Evaluation of these methods reveals that, although both are efficient in small-scale experiments, they are inoperative for the production of positron emission tomography (PET) tracers. Since high base content turned out to be responsible for low radiochemical conversions, a "low base" protocol has been developed which affords 18F-labeled arenes from diaryliodonium salts and aryl pinacol boronates in reasonable yields. Furthermore, implementation of our "minimalist" approach to the copper-mediated [18F]-fluorination of (mesityl)(aryl)iodonium salts allows the preparation of 18F-labeled arenes in excellent RCCs. The novel radiofluorination method circumvents time-consuming azeotropic drying and avoids the utilization of base and other additives, such as cryptands. Furthermore, this procedure enables the production of clinically relevant PET tracers; [18F]FDA, 4-[18F]FPhe, and [18F]DAA1106 are obtained in good isolated radiochemical yields. Additionally, [18F]DAA1106 has been evaluated in a rat stroke model and demonstrates excellent potential for visualization of translocator protein 18 kDa overexpression associated with neuroinflammation after ischemic stroke.
- Zlatopolskiy, Boris D.,Zischler, Johannes,Krapf, Philipp,Zarrad, Fadi,Urusova, Elizaveta A.,Kordys, Elena,Endepols, Heike,Neumaier, Bernd
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supporting information
p. 5972 - 5979
(2015/03/31)
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- Titania-catalyzed radiofluorination of tosylated precursors in highly aqueous medium
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Nucleophilic radiofluorination is an efficient synthetic route to many positron-emission tomography (PET) probes, but removal of water to activate the cyclotron-produced [18F]fluoride has to be performed prior to reaction, which significantly increases overall radiolabeling time and causes radioactivity loss. In this report, we demonstrate the possibility of 18F-radiofluorination in highly aqueous medium. The method utilizes titania nanoparticles, 1:1 (v/v) acetonitrile-thexyl alcohol solvent mixture, and tetra-n-butylammonium bicarbonate as a phase-transfer agent. Efficient radiolabeling is directly performed with aqueous [18F]fluoride without the need for a drying/azeotroping step to significantly reduce radiosynthesis time. High radiochemical purity of the target compound is also achieved. The substrate scope of the synthetic strategy is demonstrated with a range of aromatic, aliphatic, and cycloaliphatic tosylated precursors.
- Sergeev, Maxim E.,Morgia, Federica,Lazari, Mark,Wang, Christopher,Van Dam, R. Michael
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p. 5686 - 5694
(2015/05/20)
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- Automated radiosynthesis of no-carrier-added 4-[18F] fluoroiodobenzene: A versatile building block in 18F radiochemistry
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4-[18F]Fluoroiodobenzene ([18F]FIB) is a versatile building block in 18F radiochemistry used in various transition metal-mediated C-C and C-N cross-coupling reactions and [18F] fluoroarylation reactions. Various
- Way, Jenilee Dawn,Wuest, Frank
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p. 104 - 109
(2014/03/21)
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- Radiofluorination of diaryliodonium tosylates under aqueous-organic and cryptand-free conditions
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Positron emission tomography (PET) has growing importance as a molecular imaging technique in clinical research and drug development. Methods for producing PET radiotracers utilizing cyclotron-produced [18F]fluoride ion (t1/2 = 109.7
- Chun, Joong-Hyun,Telu, Sanjay,Lu, Shuiyu,Pike, Victor W.
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supporting information
p. 5094 - 5099
(2013/08/15)
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- 18F-radiolabeling of aromatic compounds using triarylsulfonium salts
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A new method for the 18F-radiolabeling of aromatic compounds based on the aromatic nucleophilic substitution (SNAr) reaction using triarylsulfonium salts has been developed. Experiments and DFT calculations indicated that sulfonium i
- Mu, Linjing,Fischer, Cindy R.,Holland, Jason P.,Becaud, Jessica,Schubiger, P. August,Schibli, Roger,Ametamey, Simon M.,Graham, Keith,Stellfeld, Timo,Dinkelborg, Ludger M.,Lehmann, Lutz
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supporting information; experimental part
p. 889 - 892
(2012/04/04)
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- Syntheses of meta-[18F]fluorobenzaldehyde and meta-[ 18F]fluorobenzylbromide from phenyl(3-Formylphenyl) iodonium salt precursors
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18F-labeled fluorobenzaldehydes and fluorobenzylbromides are useful synthons for the preparation of positron emission tomography radiopharmaceuticals. Although ortho- and para-[18F] fluorobenzaldehydes can easily be prepared with high yields, the corresponding meta-derivatives are more problematic. In order to improve the yield of meta-[18F]fluorobenzaldehyde, we used the corresponding diaryliodonium salt precursors, since diaryliodonium salts had already been used as precursors in the preparations of 18F-labeled electron-rich, as well as electron-deficient, aromatic rings. Diaryliodonium salts with different counter ions [PhIPhCHO]X (X = Cl, Br, OTs, OTf) were synthesized. 18F radiolabeling was performed using different bases at different temperatures in the presence of a radical scavenger, 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO). The best conversion (~80%) to meta-[18F] fluorobenzaldehyde was obtained using CsHCO3 base at a reaction temperature of 110°C. To study iodonium salt counter ion effects on radiofluorination, each precursor was separately treated with Cs[ 18F]F/CsHCO3 in DMF at 110°C for 5 min in the presence of TEMPO. Our observed reactivity order was OTs18F]fluorobenzaldehyde thus obtained was reduced to the corresponding alcohol with aqueous NaBH4 at room temperature and then converted to meta-[18F]fluorobenzylbromide using triphenylphosphine dibromide. Formation of meta-[18F]fluorobenzylbromide was confirmed using high-performance liquid chromatography and the desired product was purified on a silica Sep-Pak plus cartridge. Copyright
- Basuli, Falguni,Wu, Haitao,Griffiths, Gary L.
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experimental part
p. 224 - 228
(2012/05/20)
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- Rapid and efficient radiosyntheses of meta-substituted [ 18F]fluoroarenes from [18F]fluoride ion and diaryliodonium tosylates within a microreactor
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Effective methods for the introduction of the short-lived positron-emitter fluorine-18 (t1/2 = 109.7 min) at high specific radioactivity into fluoroarenes are valuable for the development of radiotracers for molecular imaging with positron emis
- Chun, Joong-Hyun,Lu, Shuiyu,Pike, Victor W.
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experimental part
p. 4439 - 4447
(2011/10/08)
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- Nucleophilic [18F]Fluorination and subsequent decarbonylation of methoxy-substituted nitro- and halogen-benzenes activated by one or two formyl groups
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As model reactions for the introduction of 18F into protected aromatic amino acids, the replacement of NO2, Cl, Br and F by [ 18F]fluoride in 2-isophthalaldehyde and 2-terephthalaldehyde derivatives which model 18/su
- Shen, Bin,Loeffler, Dirk,Reischl, Gerald,Machulla, Hans-Juergen,Zeller, Klaus-Peter
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experimental part
p. 113 - 119
(2011/08/03)
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- NO-CARRIER-ADDED NUCLEOPHILIC [F-18] FLUORINATION OF AROMATIC COMPOUNDS
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Phenyliodonium ylide derivatives substituted with electron donating as well as electron withdrawing groups on the aromatic ring are shown for use as precursors in aromatic nucleophilic substitution reactions. The iodonium ylide group is substituted by nucleophiles such as halide ions to provide the corresponding haloaryl derivatives. No- carrier-added [F-18]fluoride ion exclusively substitutes the iodonium ylide moiety in these derivatives and provides high specific activity F- 18 labeled fluoro derivatives. Protected L-dopa-6-iodonium ylide derivative have been synthesized as a precursors for the preparation of no-carrier-added 6-[F- 18]fluoro-L-dopa. The iodonium ylide group in this L-dopa.derivative is nucleophilically substituted by no-carrier-added [F-18]fluoride ion to provide a [F-18]fluoro intermediates which upon acid hydrolysis yielded 6-[F- 18]fluoro-L-dopa.
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Page/Page column 13-15
(2010/11/03)
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- Fast and high-yield microreactor syntheses of ortho -substituted [ 18F]Fluoroarenes from reactions of [18F]Fluoride ion with diaryliodonium salts
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A microreactor was applied to produce ortho-substituted [ 18F]fluoroarenes from the reactions of cyclotron-produced [ 18F]fluoride ion (t1/2 = 109.7 min) with diaryliodonium salts. The microreactor provided a very convenient means for running sequential reactions rapidly with small amounts of reagents under well-controlled conditions, thereby allowing reaction kinetics to be followed and Arrhenius activation energies (Ea) to be measured. Prepared symmetrical iodonium chlorides (Ar2I+Cl-) rapidly (6H4, 51%) to high (Ar = Ph or 2-MeC6H4, 85%) decay-corrected radiochemical yields (RCYs) of a single radioactive product (Ar18F). Reaction velocity with respect to Ar group was 2-MeOC6H4 6H4. Activation energies were in the range 18-28 kcal/mol. Prepared unsymmetrical salts (e.g., 2-RC6H 4I+2′-R′C6H4X -; X = Cl or OTs) also rapidly gave two products (2-RC 6H418F and 2-R′C6H 418F) in generally high total RCYs (79-93%). Selectivity for product [18F]fluoroarene was controlled by the nature of the ortho substituents. The power of ortho substituents to impart an ortho-effect was in the following order:, 2,6-di-Me > 2,4,6-tri-Me > Br > Me > Et ≈ iPr ? H > OMe. For (2-methyphenyl)(phenyl)iodonium chloride, the time-course of reaction product selectivity was constant and consistent with the operation of the Curtin-Hammett principle. These results will aid in the design of diaryliodonium salt precursors to 18F- labeled tracers for molecular imaging. This article not subject to U.S. Copyright. Published 2010 by the American Chemical Society.
- Chun, Joong-Hyun,Lu, Shuiyu,Lee, Yong-Sok,Pike, Victor W.
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experimental part
p. 3332 - 3338
(2010/08/20)
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- NUCLEOPHILIC FLUORINATION OF AROMATIC COMPOUNDS
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Iodylbenzene derivatives substituted with electron donating as well as electron withdrawing groups on the aromatic ring are used as precursors in aromatic nucleophilic substitution reactions. The iodyl group (IO2) is regiospecifically substituted by nucleophilic fluoride to provide the corresponding fluoroaryl derivatives. No-carrier-added [F-18] fluoride ion derived from anhydrous [F- 18]KF/Kryptofix, [F-18]CsF or a quaternary ammonium fluoride (e.g., Me4NF, Et4NF, n-Bu4NF, (PhCH2)4NF) exclusively substitutes the iodyl moiety in these derivatives and provides high specific activity F- 18 labeled fluoroaryl analogs. Iodyl derivatives of a benzothiazole analog and 6-iodyl-L-dopa derivatives have been synthesized as precursors and have been used in the preparation of no-carrier-added [F-18]fluorobenzothiazole as well as 6-[F-18]fluoro-L-dopa.
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Page/Page column 12-13
(2010/04/03)
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- A practical route for synthesizing a PET ligand containing [18F]fluorobenzene using reaction of diphenyliodonium salt with [18F]F-
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The aim of this study was to develop a practical route for preparing a fluorine-18 ([18F]) labelled ligand ([18F]1) containing [18F]fluorobenzene ring by employing the reaction of diphenyliodonium salt with [18F]F-. Diphenyliodonium tosylate (2) was synthesized from tributylphenylstannyl compound (6) with [hydroxy(tosyloxy)iodo]benzene (7). Using this method, [18F]DAA1106 ([18F]3a), a positron emission tomography ligand for imaging peripheral-type benzodiazepine receptor, was prepared.
- Zhang, Ming-Rong,Kumata, Katsushi,Suzuki, Kazutoshi
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p. 8632 - 8635
(2008/03/30)
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- [18F]Fluorophenyl organometallics as intermediates of no-carrier-added 18F-fluoroarylation reactions
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Based on the recent availability of no-carrier-added (n.c.a.) 1-bromo-4-[18F]fluorobenzene with high radiochemical yield, the 4-[18F]fluorophenyl compounds of lithium, sodium and magnesium can now also effectively be prepared. Thus,
- Ermert, Johannes,Ludwig, Thomas,Gail, René,Coenen, Heinz H.
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p. 4084 - 4092
(2008/02/10)
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- Nucleophilic 18F-fluorination of heteroaromatic iodonium salts with no-carrier-added [18F]fluoride
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Diaryliodonium salts containing the 2-thienyl group as an example of an electron-rich heteroaromatic moiety proved to be very potent precursors for the nucleophilic, regioselective no-carrier-added (nca) radiofluorination of various arenes. It even allowe
- Ross, Tobias L.,Ermert, Johannes,Hocke, Carsten,Coenen, Heinz H.
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p. 8018 - 8025
(2008/02/09)
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- FLUORIDATION METHOD
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A method for the fluoridation of an iodonium salt with a fluoride ion source which can be carried out in an aqueous reaction solvent.
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Page/Page column 14; 17
(2010/02/14)
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- Comparison of pathways to the versatile synthon of no-carrier-added 1-bromo-4-[18F]fluorobenzene
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The availability of no-carrier-added (n.c.a.) 1-bromo-4-[ 18F]fluorobenzene with high radiochemical yields is important for 18F-arylation reactions using metallo-organic 4-[18F] fluorophenyl compounds (e.g. of lithium or m
- Ermert, Johannes,Hocke, Carsten,Ludwig, Thomas,Gail, Rene,Coenen, Heinz H.
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p. 429 - 441
(2007/10/03)
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- The synthesis of [18F]fluoroarenes from the reaction of cyclotron-produced [18F]fluoride ion with diaryliodonium salts
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Diaryliodonium salts have been shown to react with fluoride ion at 80°C in acetonitrile to generate aryl fluorides. The regioselectivity is controlled electronically and by the bulk of the ortho-substituents on the rings, with the latter the dominant factor such that electron-rich rings can be fluorinated. ortho-Substituted aryl fluorides can be selectively produced from unsymmetrical diaryliodonium salts. The process has been used to synthesise [18F] labelled aromatics by the use of cyclotron generated [18F]fluoride ion.
- Shah, Aneela,Pike, Victor W.,Widdowson, David A.
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p. 2043 - 2046
(2007/10/03)
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- REGIOSPECIFIC AROMATIC FLUORODEMETALLATION OF GROUP IVb METALLOARENES USING ELEMENTAL FLUORINE OR ACETYL HYPOFLUORITE
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The reactions of fluorine and acetyl hypofluorite with trimethylaryltin,- germanium, and- silicon compounds were studied using fluorine-18 (T1/2 = 110 min) as a radiochemical tracer.The fluoro-demetallation of phenyl derivatives by sub-stoichio
- Coenen, H.H.,Moerlein, S. M.
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- ELECTROPHILIC RADIOFLUORATION OF ARYLTRIMETHYLSILANES AS A GENERAL ROUTE TO 18F-LABELED ARYL FLUORIDES
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The reaction of a variety of aryltrimethylsilanes with elemental fluorine and acetyl hypofluorite have been studied with the aim of developing a general method for labeling aromatic compounds with fluorine-18.Extensive 18F incorporation into the aromatic ring of the selected aryltrimethylsilanes was invariably observed, leading to the ipso(18F-for Si) electrophilic substitution products together with variable yields of other (18F-for-H) electrophilic substitution products.The relative extent of the 18F substitution processes subst.> is found to depend largely upon the substituent group on the aromatic ring of the substrate, the leaving moiety, and the radiofluoration procedure used.The utility of aryltrimethylsilyl derivates as precursors for the rapid synthesis of high specific activity of 18F-labeled radiopharmaceuticals is discussed.
- Speranza, M.,Shiue, C.-Y.,Wolf, A. P.,Wilbur, D. S.,Angelini, G.
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- The 18F Radiofluorination of Arylsilanes
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The synthesis of 18F labelled compounds by cleaving silanes with F2 is reported.
- Raddo, Pasquale Di,Diksic, Mirko,Jolly, Dean
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p. 159 - 160
(2007/10/02)
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