8.1 INTRODUCTION

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413. Westerberg, G., Kärger, W., Onoe, H., and Långström, B. (1994). [11C]Cyanogen bromide in the synthesis of 1,3-di(2-tolyl)-[

C]guanidine. J. Labelled Compd. Radiopharm. 34

(8): 691–696.

414 Westerberg, G., Bergström, M., Gustafson, S. etal. (1995). Labelling of polysaccha-

rides using [

C]cyanogen bromide. In vivo and in vitro evaluation of 11C-hyaluronan

uptake kinetics. Nucl. Med. Biol. 22 (2): 251–256.

415. Emran, A.M., Boothe, T.E., Finn, R.D. etal. (1983). Preparation of carrier-added

C-cyanide. Int. J. Appl. Radiat. Isot. 34 (7): 1013–1014.

C-urea from no-

416. Emran, A.M., Boothe, T.E., Finn, R.D. etal. (1985). Optimized production of high specic activity [

C]urea. Int. J. Appl. Radiat. Isot. 36 (9): 739–740.

417. Vander Borght, T., Labar, D., Pauwels, S., and Lambotte, L. (1991). Production of

[2-

C]thymidine for quantication of cellular proliferation with PET. Int. J. Radiat.

Appl. Instrum. 42 (1): 103–104.

418 Emran, A.M., Boothe, T.E., Finn, R.D. etal. (1986). Use of

ing the synthesis of radiolabelled compounds—II: 2-[

from [

C]cyanide. Int. J. Radiat. Appl. Instrum. A Appl. Radiat. Isot. 37 (10):

C as a tracer for study-

C]-5,5-diphenylhydantoin

1033–1038.

419. Westerberg, G. and Långström, B. (1994). Synthesis of sodium [

[

C]cyanogen bromide. J. Labelled Compd. Radiopharm. 34 (6): 545–548.

420. Stone-Elander, S., Roland, P., Halldin, C. etal. (1989). Synthesis of [

C]thiocyanate using

C]sodium thiocyanate for in vivo studies of anion kinetics using positron emission tomography (PET). Int. J. Rad. Appl. Instrum. B 16 (7): 741–746.

421 Haywood, T., Cesarec, S., Kealey, S. etal. (2018). Ammonium [

C]thiocyanate: revised preparation and reactivity studies of a versatile nucleophile for carbon-11 radiolabelling. Medchemcomm 9 (8): 1311–1314.

422. Johnström, P., Bergman, L., Varnäs, K. etal. (2015). Development of rapid multistep carbon-11 radiosynthesis of the myeloperoxidase inhibitor AZD3241 to assess brain exposure by PET microdosing. Nucl. Med. Biol. 42 (6): 555–560.

423. Saeed, M., Tewson, T.J., Erdahl, C.E., and Kohen, A. (2012). A fast chemoenzymatic synthesis of [

C]-N5,N10-methylenetetrahydrofolate as a potential PET tracer for

proliferating cells. Nucl. Med. Biol. 39 (5): 697–701.

424. Hughes, J.A., Hartman, N.G., and Jay, M. (1995). Preparation of [

[

C]-2′-arabino-2′-uoro-β-5-methyl-uridine (FMAU) using a hollow ber membrane

C]-thymidine and

bioreactor system. J. Labelled Compd. Radiopharm. 36 (12): 1133–1145.

425. Neelamegam, R., Hellenbrand, T., Schroeder, F.A. etal. (2014). Imaging evaluation of 5HT2 cagonists, [

C]WAY-163909 and [11C]vabicaserin, formed by Pictet-Spengler

cyclization. J. Med. Chem. 57 (4): 1488–1494.

426. Hanyu, M., Takada, Y., Hashimoto, H. etal. (2013). Carbon-11 radiolabeling of an oligopeptide containing tryptophan hydrochloride via a Pictet-Spengler reaction using carbon-11 formaldehyde. J. Pept. Sci. 19 (10): 663–668.

427. Mathews, W.B., Nakamoto, Y., Abraham, E.H. etal. (2005). Synthesis and biodistribution of [

C]adenosine 5′-monophosphate ([11C]AMP). Mol. Imaging Biol. 7

(3): 203–208.

 245

428. Roeda, D., Sipil, H.T., Bramoull, Y. etal. (2002). Synthesis of [11C]atipamezole, a potential PET ligand for the Α2-adrenergic receptor in the brain. J. Labelled Compd. Radio- pharm. 45 (1): 37–47.

429. Popkov, A. and Itsenko, O. (2015). An asymmetric approach to the synthesis of a carbon-11 labelled gliotransmitter D-serine. J. Radioanal. Nucl. Chem. 304 (1): 455–458.

430. Straatmann, M.G. and Welch, M.J. (1975). A general method for labeling proteins

with

C. J. Nucl. Med. 16 (5): 425–428.

431. Wu, C., Li, R., Dearborn, D., and Wang, Y. (2012). Reductive amination with [

C]formaldehyde: a versatile approach to radiomethylation of amines. Int. J. Org. Chem. 02 (03): 202–223.

432. Roeda, D. and Dolle, F. (2010). [

C]Phosgene: a versatile reagent for radioactive carbonyl insertion into medicinal radiotracers for positron emission tomography. Curr. Top. Med. Chem. 10 (16): 1680–1700.

433. Crouzel, C., Hinnen, F., and Maitre, E. (1995). Radiosynthesis of methyl and heptyl

[

C]isocyanates from [11C]phosgene, application to the synthesis of carbamates: [11C]

physostygmine and [

434. Brown, G.D., Henderson, D., Steel, C. etal. (2001). Two routes to [ organo-isocyanates utilizing [

C]heptylphysostigmine. Appl. Radiat. Isot. 46 (3): 167–170.

C-carbonyl]

C]phosgene ([11C]organo-Isocyanates from [11C]phos-

gene). Nucl. Med. Biol.: 991–998.

435. Dollé, F., Martarello, L., Bramoullé, Y. etal. (2005). Radiosynthesis of carbon-11-labelled GI181771, a new selective CCK-A agonist. J. Labelled Compd. Radiopharm. 48 (7): 501–513.

436. Shimoda, Y., Yui, J., Zhang, Y. etal. (2015). Radiosynthesis and evaluation of N-(3,4dimethylisoxazol-5-Yl)piperazine-4-[4-(4-uorophenyl)thiazol-2-yl]-1-[

C]carboxamide for in vivo positron emission tomography imaging of fatty acid amide hydrolase in brain. RSC Adv. 5 (128): 106122–106127.

437. Asakawa, C., Ogawa, M., Fujinaga, M. etal. (2012). Utilization of [ radiosynthesis of N-(2-{3-[3,5-bis(triuoromethyl)]phenyl[

C]phosgene for

C]ureido}ethyl) glycyrrhetinamide, an inhibitory agent for proteasome and kinase in tumors. Bioorg. Med. Chem. Lett. 22 (11): 3594–3597.

438. Asakawa, C., Ogawa, M., Kumata, K. etal. (2011). Sorafenib: radiosynthesis and preliminary PET study of brain uptake in P-Gp/Bcrp knockout mice. Bioorg. Med. Chem. Lett. 21 (8): 2220–2223.

439. Asakawa, C., Ogawa, M., Kumata, K. etal. (2011). Radiosynthesis of three [

C]Ureido-substituted benzenesulfonamides as PET probes for carbonic anhydrase IX in tumors. Bioorg. Med. Chem. Lett. 21 (23): 7017–7020.

440. Lemoucheux, L., Rouden, J., Ibazizene, M. etal. (2003). Debenzylation of tertiary amines using phosgene or triphosgene: an ecient and rapid procedure for the preparation of carbamoyl chlorides and unsymmetrical ureas. Application in carbon-11 chemistry. J. Org. Chem. 68 (19): 7289–7297.

441. Dolle, F., Valette, H., Hinnen, F. etal. (2001). Synthesis and preliminary evaluation of a carbon-11-labelled agonist of the Α7 nicotinic acetylcholine receptor. J. Labelled Compd. Radiopharm. 44 (11): 785–795.

246 Handbook of Radiopharmaceuticals

442. Lidström, P., Bonasera, T.A., Marquez-M, M. etal. (1998). Synthesis and in vitro evaluation of [carbonyl-

C]estramustine and [carbonyl-11C]estramustine phosphate. Ste-

roids 63 (4): 228–234.

443. Kumata, K., Yui, J., Hatori, A. etal. (2015). Development of [

C]MFTC for PET imaging of fatty acid amide hydrolase in rat and monkey brains. ACS Chem. Neurosci. 6 (2): 339–346.

444. Wang, L., Mori, W., Cheng, R. etal. (2016). Synthesis and preclinical evaluation of sulfonamidobased [

C-carbonyl]-carbamates and ureas for imaging monoacylglycerol

lipase. Theranostics 6 (8): 1145–1159.

445. Cheng, R., Mori, W., Ma, L. etal. (2018). In vitro and in vivo evaluation of

C-labeled azetidinecarboxylates for imaging monoacylglycerol lipase by PET imaging studies. J. Med. Chem. 61 (6): 2278–2291.

446. Damont, A., Roeda, D., and Dollé, F. (2013). The potential of carbon-11 and uorine-18 chemistry: illustration through the development of positron emission tomography radioligands targeting the translocator protein 18 KDa. J. Labelled Compd. Radiopharm. 56 (3–4): 96–104.

447 Miller, P.W., Kato, K., and Långström, B. (2014). Carbon-11, nitrogen-13, and

oxygen-15 chemistry: an introduction to chemistry with short-lived radioisotopes. In: The Chemistry of Molecular Imaging, vol. 9781118093 (eds. N. Long and W.-.T. Wong), 79–103. Hoboken, NJ: Wiley.

448. Del Vecchio, A., Destro, G., Taran, F., and Audisio, D. (2018). Recent developments in heterocycle labeling with carbon isotopes. J. Labelled Compd. Radiopharm. 61 (13): 988–1007.

449. Roeda, D., Tavitian, B., Coulon, C. etal. (1997). Synthesis of [

C]RPR-72840A and its evaluation as a radioligand for the serotonin reuptake site in positron emission tomography. Bioorg. Med. Chem. 5 (2): 397–403.

450. Yashio, K., Katayama, Y., Takashima, T. etal. (2012). Synthesis of [

[

C]phosgene, as a possible biomarker in PET imaging for diagnosis of gout. Bioorg.

C]uric acid, using

Med. Chem. Lett. 22 (1): 115–119.

451 Takada, Y., Ogawa, M., Suzuki, H., and Fukumura, T. (2010). Radiosynthesis of [2-

bonyl]dantrolene using [

452. Seki, K.I., Nishijima, K.I., Sanoki, K. etal. (2009). New [

of [

C]pyrimidines for positron emission tomography. Heterocycles 77 (2): 1307–1321.

C]phosgene for PET. Appl. Radiat. Isot. 68 (9): 1715–1720.

C]phosgene based synthesis

C-car-

453. Roger, G., Dollé, F., De Bruin, B. etal. (2004). Radiosynthesis and pharmacological evaluation of [

C]EMD-95885: a high anity ligand for NR2B-containing NMDA

receptors. Bioorg. Med. Chem. 12 (12): 3229–3237.

454. Roger, G., Lagnel, B., Besret, L. etal. (2003). Synthesis, radiosynthesis and in vivo evaluation of 5-[3-(4-benzylpiperidin-1-yl)prop-1-ynyl]-1,3-dihydrobenzoimidazol-

2-[

C]one, as a potent NR1A/2B subtype selective NMDA PET radiotracer. Bioorg.

Med. Chem. 11 (24): 5401–5408.

455. Labas, R., Sobrio, F., Bramoullé, Y. etal. (2010). Radiosynthesis of N-[4-(4-uorobenzyl) piperidin-1-yl]-N’-(2-[

C]oxo-1,3-dihydrobenzimidazol-5-yl)oxamide, a NR2B-selective

NMDA receptor antagonist. J. Labelled Compd. Radiopharm. 53 (2): 63–67.

 247

456. Brown, G.D., Luthra, S.K., Brock, C.S. etal. (2002). Antitumor imidazotetrazines.

40. 1 radiosyntheses of [4-

C-Carbonyl]- and [3-N-11C-methyl]-8-carbamoyl-3methylimidazo[5,1-d]-1,2,3,5-tetrazin-4(3H)-one (temozolomide) for positron emission tomography (PET) studies. J. Med. Chem. 45 (25): 5448–5457.

457. Kato, K., Gustavsson, S.Å., and Långström, B. (2008). Asymmetric nitroaldol reaction using nitromethane labeled with

458. Zessin, J. and Steinbach, J. (1998). ring positions: synthesis of [2-

C. Tetrahedron Lett. 49 (41): 5837–5839.

C-labelling of heterocyclic aromatic compounds in

C]indole. J. Labelled Compd. Radiopharm. 41 (7): 669–676.

459. Schoeps, K.O., Långström, B., Stone-Elander, S., and Halldin, C. (1991). Synthesis of

[1-

C]D-glucose and [1-11C]D-mannose from on-line produced [11C]nitromethane. Int.

J. Rad. Appl. Instrum. A 42 (9): 877–883.

460. Kato, K., Zhang, M.R., Minegishi, K. etal. (2011). Nitroaldol reaction of nitro[ methane to form 2-(hydroxymethyl)-2-nitro[2-

C]propane-1,3-diol and [11C]TRIS. J.

Labelled Compd. Radiopharm. 54 (3): 140–144.

461. Mäding, P., Steinbach, J., and Johannsen, B. (2000). No-carrier-added benzenoid compounds in ring positions by condensation of nitro-[

C-labelling of

C]methane with

pyrylium salts. J. Labelled Compd. Radiopharm. 43 (6): 565–583.

462. Kato, K., Zhang, M.R., and Suzuki, K. (2007). Rapid C-carboxylation of nitro[ methane for the synthesis of ethyl nitro[2-

463. Kato, K., Zhang, M.-R., and Suzuki, K. (2009). Synthesis of (R,S)-[4Michael addition of nitromethane labeled with short-lived

C]acetate. Mol. Biosyst. 4 (1): 53–55.

C]baclofen via

C. Bioorg. Med. Chem.

Lett. 19 (21): 6222–6224.

464. Roeda, D., Crouzel, C., Brouillet, E., and Valette, H. (1996). Synthesis and in vivo distribution of no-carrier-added N(ω)-nitro-L-arginine [

C]methyl ester, a nitric oxide

synthase inhibitor. Nucl. Med. Biol. 23 (4): 509–512.

465. Dollé, F., Hinnen, F., Valette, H. etal. (1997). Synthesis of two optically active calcium channel antagonists labelled with carbon-11 for in vivo cardiac PET imaging. Bioorg. Med. Chem. 5 (4): 749–764.

466. Neu, H., Bonasera, T.A., and Langström, B. (1998). Lithium[ cuprate·LiCN in 1,4-addition to α,β -unsaturated ketones,

C]methyl(2-thienyl)

C and 13C labelling of the

androgen mesterolone. J. Labelled Compd. Radiopharm. 41 (3): 227–234.

467. Lidström, P., Neu, H., and Långström, B. (1997). Syntheses of [21-

C] and [21-13C]pro-

gesterone. J. Labelled Compd. Radiopharm. 39 (8): 695–704.

468. da Silva, E.S., Gómez-Vallejo, V., López-Gallego, F., and Llop, J. (2018). Biocatalysis in radiochemistry: enzymatic incorporation of PET radionuclides into molecules of biomedical interest. J. Labelled Compd. Radiopharm. 61 (4): 332–354.

469. Barrio, J.R., Egbert, J.E., Henze, E. etal. (1982). L-[4-

C]aspartic acid: enzymatic synthesis,

myocardial uptake, and metabolism. J. Med. Chem. American Chemical Society: 93–96.

470. Antoni, G., Omura, H., Ikemoto, M. etal. (2001). Enzyme catalysed synthesis of L-[4-

C] aspartate and L-[5-11C] glutamate. J. Labelled Compd. Radiopharm. 44 (4): 287–294.

471. Antoni, G., Omura, H., Bergström, M. etal. (1997). Synthesis of L-2,4-diamino[4-

C] butyric acid and its use in some in vitro and in vivo tumour models. Nucl. Med. Biol. 24 (6): 595–601.

248 Handbook of Radiopharmaceuticals

472. Svärd, H., Jigerius, S.B., and Långström, B. (1990). The enzymatic synthesis of L-[3-11C] serine. Int. J. Radiat. Appl. Instrum. 41 (6): 587–591.

473. Kaneko, S., Ishiwata, K., Ishii, S.I. etal. (1999). Enzymatic synthesis of carbon-11 labeled methionine and its derivatives with immobilized γ-cyano-γ-aminobutyric acid synthase. Appl. Radiat. Isot. 51 (3): 285–291.

474. Mannens, G., Slegers, G., Lambrecht, R., and Goethals, P. (1988). Enzymatic synthesis of carbon-11 acetyl coenzyme A. J. Labelled Compd. Radiopharm. 25 (7): 695–705.

475. Jacobson, G.B., Watanabe, Y., Valind, S. etal. (1997). Synthesis of O-[

O-[

C]acetyl-L-carnitine, and L-[11C]carnitine labelled in specic positions, applied in

C]acetyl CoA,

PET studies on rhesus monkey. Nucl. Med. Biol. 24 (5): 471–478.

476 Davenport, R.J., Pike, V.W., Dowsett, K. etal. (1997). Automated chemoenzymatic

synthesis of no-carrier-added [carbonyl-

C]propionyl L-carnitine for pharmacokinetic

studies. Appl. Radiat. Isot. 48 (7): 917–924.

477. Mannens, G., Slegers, G., Goethals, P., and Claeys, A. (1990). Enzymatic synthesis of carbon-11 N-acetyl-D-glucosamine. J. Labelled Compd. Radiopharm. 28 (1): 53–64.

478. Mannens, G., Slegers, G., and Goethals, P. (1990). Enzymatic synthesis of [

C]N-ace-

tylserotonin. J. Labelled Compd. Radiopharm. 28 (3): 311–320.

479. Ikemoto, M., Sasaki, M., Haradahira, T. etal. (1999). Synthesis of L-[β-

C]amino acids

using immobilized enzymes. Appl. Radiat. Isot. 50 (4): 715–721.

480. Bjurling, P., Antoni, G., Malmborg, P. etal. (1991). Multi-enzymatic syntheses of L-tyrosine and L-DOPA.

C labeling in two positions. Acta Radiol. Suppl. 376: 107–108.

481. Bjurling, P., Antoni, G., Watanabe, Y., and Langstrom, B. (1990). Enzymatic synthesis of carboxy-

C-labelled L-tyrosine, L-DOPA, L-tryptophan and 5-hydroxy-L-trypto-

phan. Acta Chamiça Scand. 44: 178–182.

482 Harada, N., Nishiyama, S., Sato, K., and Tsukada, H. (2000). Development of an

automated synthesis apparatus for L-[3-

C] labeled aromatic amino acids. Appl.

Radiat. Isot. 52 (4): 845–850.

483. Carlson, E.D., Gan, R., Hodgman, C.E., and Jewett, M.C. (2012). Cell-free protein synthesis: applications come of age. Biotechnol. Adv. Elsevier: 1185–1194.

484. Matsuda, T., Furumoto, S., Higuchi, K. etal. (2012). Rapid biochemical synthesis of

C-labeled single chain variable fragment antibody for immuno-PET by cell-free pro-

tein synthesis. Bioorg. Med. Chem. 20 (22): 6579–6582.

485. Harada, R., Furumoto, S., Yoshikawa, T. etal. (2012). Synthesis of [ a cell-free translation system and L-[

C]methionine. Nucl. Med. Biol. 39 (1): 155–160.

C]interleukin 8 using

486. Gueguen, P., Morgat, J.-L., Maziere, M. etal. (1982). Enzymatic synthesis of

C-labelled S-adenosylmethionine. J. Labelled Compd. Radiopharm. 19 (2): 157–170.

487. Tremblay, S., Ouellet, R., Bénard, F., and Cunnane, S.C. (2008). Automated synthesis of

C-β-hydroxybutyrate by enzymatic conversion of 11C-acetoacetate using

β-hydroxybutyrate dehydrogenase. J. Labelled Compd. Radiopharm. 51 (5): 242–245.

488. Garcia-Arguello, S.F., Fortt, R., Steel, C.J. etal. (2013). Radiosynthesis of the D2/3 agonist [3-

C]-(+)-PHNO using [11C]iodomethane Appl. Radiat. Isot 73: 79–83.-

 249

Chapter 8

Fluorine-18 Radiochemistry

Allen F. Brooks

Department of Radiology, University of Michigan, Ann Arbor, MI, 48109, USA

Katarina J. Makaravage

Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA

Jay Wright

Department of Radiology, University of Michigan, Ann Arbor, MI, 48109, USA

Melanie S. Sanford

Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA

Peter J. H. Scott

Department of Radiology, University of Michigan, Ann Arbor, MI, 48109, USA

8.1 INTRODUCTION

Between the publication of the rst edition of the Handbook of Radiopharmaceuticals and this new edition, interest in uorine-18, its applications, and utilization have continued to grow. This is reected in the increasing number of publications and patents containing uorine-18 as a key feature of the work (Figure8.1). Cyclotron produced uorine-18

Handbook of Radiopharmaceuticals: Methodology and Applications, Second Edition. Edited by Michael R. Kilbourn and Peter J.H. Scott. © 2021 John Wiley & Sons Ltd. Published 2021 by John Wiley & Sons Ltd.

3500

3000

2500

2000

500

3000

2500

2000

1996 2001 2006 2011 2016

1960–2017 Publications

000

500

1960

1970 1980 1990

1997–2017 Scientific Literature Publications 1997–2017 Patents

500

000

500

Figure 8.1 Fluorine-18 scientic and patent literature. Source: Data from Scopus.

is readily available primarily from commercial nuclear pharmacies (which require it for

[

F]uorodeoxyglucose ([18F]FDG) production) and academic medical research centers, which has been a factor in this growth as more sites and researchers can start programs with smaller investments in infrastructure. Alongside this increased interest, the trend toward the utilization of nucleophilic [

like [

F]F2, has continued. This is due to the amount of high-molar-activity [18F]uoride that can be conveniently produced in easy-to-handle aqueous solutions. For example, the bulk of new methodology research and positron emission tomography (PET) tracer development with uorine-18 has utilized small medical cyclotrons to produce [ uoride ([

F]F−) via proton irradiation of [18O]H2O according to the 18O(p,n)18F nuclear reaction. New uorine-18 radiochemistry has been extensively reviewed in recent years[1–20], and this chapter will focus on highlighting key new methods utilizing [ as a reagent for the production of uorine-18 PET imaging agents.

At the time of the previous edition of the Handbook, the two main approaches to

radiolabeling with [

F]uoride were nucleophilic substitution reactions (SN2) of aliphatic compounds and nucleophilic aromatic substitution (S challenging substrates (e.g. electron-rich arenes) or molecules previously labeled with a

252 Handbook of Radiopharmaceuticals

2000 2010

700

600

500

400

300

200

100

F]F− sources such as [18F]KF, over [18F]F+ sources

Ar) of aromatic compounds. For

F]F−

carbon-11 methyl group, an alternative approach involving the use of prosthetic groups such as the [

F]uoroethyl tosylate group[21] or N-succinimidyl 4-[18F]uorobenzoate[22, 23] were employed. These approaches are still used extensively in uorine-18 radiochemistry, but they only allow for the labeling of a limited set of potential molecules of interest for study by PET imaging.

In the past 15 years, extensive work has been done to improve the chemical space

that can be labeled with uorine-18. A signicant challenge is improving the reactivity

of [

F]KF to a level comparable to reagents such as anhydrous HF and F+ sources. To facilitate this, many productive collaborations between radiochemists and organometallic chemists have developed, and the results have disrupted many of the established notions, dogma, and limitations of uorine-18 chemistry previously accepted.

 

A standard procedure is often undertaken to process [18F]uoride obtained as a solution

in [

O]H2O from a cyclotron. Typically, [18F]uoride is trapped on a quaternary methylammonium (QMA) ion-exchange resin that has been preconditioned with carbonate or bicarbonate, allowing recovery of [ solution such as aqueous K

2CO3

acetonitrile containing Kryptox 222 (K

[

F]KF˙K

reagent is azeotropically dried in order to allow for solubility and reactivity

2.2.2

in the radiouorination step to follow. While this approach is general, a pitfall is that S reactions with uoride are prone to undesirable competing elimination reactions.

Furthermore, the use of additional base in the preconditioning of the QMA and elution of uoride can exacerbate this problem (e.g. accelerate deleterious deprotection processes). Moreover, carbonate and bicarbonate are not compatible with many catalysts or reagents, as they form unproductive mixtures. For example, copper species can form unreactive copper carbonates, inhibiting the desired radiouorination process and decreasing overall radiochemical yield (RCY). In addition, K precursors and poison reaction mixtures. As the eld has developed new methodologies over the past 15 years, PET radiochemists have given careful thought to how [ prepared as a reagent for radiolabeling in order to overcome these challenges.

The preparation of new [ of research. Reports dating back to the 1990s overcame limitations associated with the use of carbonate and its ability to degrade precursors, reagents, and/or products through the use of other anions (e.g. triate, oxalate) to condition and elute QMA cartridges. Recent work on elution scope has demonstrated that basic elution can be achieved provided that a sucient amount of solvent anion is generated. This can simply be achieved using bases with conjugate pKa constants high enough to form ions of the solvent (e.g. hydroxide in the case of H using less basic salts like KOTf, this results in [ ated in a broader set of reaction conditions, such as copper-mediated radiouorination (CMRF)[24]. For example, the Scott group was recently interested in preparing [

O]H2O. The [18F]uoride is then eluted with a basic

to generate [18F]KF. The [18F]KF is then combined with

), a phase-transfer reagent, and the resulting

2.2.2

as a nitrogen base can also degrade potential

2.2.2

F]uoride is

F]uoride sources to improve reactivity is not a new avenue

O). When utilized in conjunction with preconditioning

F]uoride reagents that can be toler-

F]AgF

Chapter 08: Fluorine-18 Radiochemistry 253

to enable access to new CH activation methods for radiouorination[25]. Several reports

of [

F]AgF were present in the literature prior to this[26–30] but required specialized equipment and conditions. Instead, by preconditioning the QMA with an anion that forms a soluble silver salt, such as triate, acetate, or nitrate (using the corresponding potassium or sodium salt), [

F]AgF can be conveniently produced[31]. In this example, changing the preconditioning agent enabled the production of a reactive silver salt that would otherwise have formed an unproductive carbonate/bicarbonate under standard elution conditions. In analogy, solvent protonation can also enable the production of different ions and the production of [ acid led to the protonation of H

[

F]HF[32]. The ability to prepare dierent forms of [18F]uoride oers scope to develop

F uoride sources. This was demonstrated in a recent report describing

F]HF, in which elution with methanesulfonic acid or triuoroacetic

O, ethanol, or N,N-Dimethylformamide (DMF) to produce

further radiouorination methods in the future.

Choice of solvent is also essential in the design of ecient radiouorination processes. Until recently, it has been accepted that the use of protic solvents would inhibit any nucleophilic radiouorination since uoride forms hydrogen bonds with them. This likely originates from nucleophilic

F uorination chemistry, which in many cases has been demonstrated to occur with increased eciency in the absence of hydrogen-bond donors (such as adventitious moisture)[33–37].

However, Stewart and co-workers described how the azeotropic drying of [

F]uoride can be conducted with ethanol instead of acetonitrile without reduction in subsequent reaction yield, oering a greener and cheaper alternative for uorine-18 processing[38]. In this report, the authors demonstrated that several precursors, including the mannose triate precursor of [

F]FDG, could be labeled in a solvent composed of ethanol and H2O (85:15). The use of ethanol over acetonitrile in the azeotropic drying step is of particular interest as it replaces a class II solvent, simplifying quality control analysis provided none are utilized in the production method (e.g. during the reaction, high-performance liquid chromatography (HPLC) purication, and/or solid-phase extraction), as was later disclosed by the Scott laboratory[39]. Furthermore, Sergeev and co-workers demonstrated that highly aqueous solvent mixtures could be utilized for the radiouorination of sulfonates in the presence of titanium catalysts. The sulfonate was postulated to coordinate to the surface of TiO both S

particles, which could also desolvate the [18F]uoride and thus facilitate

2 and SNAr reactions[40]. The use of sulfonate precursor molecules for SN2 was further explored in protic solvents by the Chi laboratory, where reaction was achieved through the formation of ionic liquids from protic solvents[41]. In their early work, 1-butyl3-methylimidazolium triate was utilized, and [ carbonate elution. Notably, the S

2 radiouorination of mesylates in this medium did not

F]uoride was prepared with cesium

require the removal of water prior to the reaction. Later, the same group also reported that if tert-butyl alcohol was utilized as a solvent and cesium carbonate was used for elution, no additive was required to convert the starting sulfonates to the corresponding

[

F]uorinated products[42]. In spite of the preference for aprotic media in a majority of radiouorination methods, protic solvents can also be utilized in uorine-18 chemistry, providing the precursor and reaction conditions are judiciously selected[43].

254 Handbook of Radiopharmaceuticals

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