Radiosynthesis of [¹⁸F]Trifluoroalkyl Groups: Scope and Limitations

Table 1

Survey of radiosynthetic approaches towards the radiosynthesis of [¹⁸F]trifluoroalkyl groups.

Method	Year	Yield/%	As (reported value) comment	Reference
(1) ^18F-^19F exchange	1979	0.5–15	Low—carrier added	Ido et al. [10]
(2) Sb2O3 catalysed ^18F-Cl substitution	1986	20–50	Low—carrier added	Angelini et al. [11, 12]
(3) ^18F-^19F exchange	1990	85	Low—(0.00002–0.002 MBq/nmol) carrier added	Kilbourn and Subramanian [13]
(4) ^18F-^19F exchange	1993	78	Low—carrier added	Aigbirhio et al. [14]
(5) ^18F-^19F exchange	1994	15–99	Low—(0.2–16.6 MBq/nmol) [15] carrier added	Satter et al. [16]
(6) ^18F-Br substitution	1990	17–28	Low—(0.037 MBq/nmol) precursor separation	Kilbourn et al. [17]
(7) ^18F-Br substitution	1993	1–4	Low—(1.5–2.5 MBq/nmol) side reaction	Das and Mukherjee [15]
(8) ^18F-Br substitution	1995	45–60	Low—(0.040–0.800 MBq/nmol) side reactions	Johnstrom and Stone-Elander [18]
(9) ^18F-fluorodesulfurisation	2001	40	Low—(0.000002 MBq/nmol) carrier added	Josse et al. [19]
(10) ^18F-Br substitution	2007	10 ± 2	Low—(4.4 ± 1.5 MBq/nmol) side reactions	Prabhakaran et al. [20]
(11) ^18F-^19F exchange	2011	~60	Low—carrier added	Suehiro et al. [21]
(12) H^18F addition	2011	52–93	Moderate (86 MBq/nmol)—side reaction	Riss and Aigbirhio [22]
(13) ^18F-I substitution	2013	60 ± 15	Not given	Van der Born et al. [23]
(14) Nucleophilic trapping of difluorocarbene formed in situ and Cu(I) mediated trifluoromethylation with Cu-[^18F]CF3	2013	5–87	Low—(0.1 MBq/nmol) side reactions	Huiban et al. [24]
(15) ^18F-I substitution, in situ formation of Cu-[^18F]CF3	2014	12–93	Low—(0.15 MBq/nmol) side reactions	Ruehl et al. [25]
(16) ^18F-F2 addition	2001	10–17	Low—carrier added	Dolbier et al. [26]
(17) ^18F-F2 disproportionation	2003	22–28	Low—(0.015–0.020 MBq/nmol) carrier-added	Prakash et al. [27]
(18) ^18F-selectfluor bis-triflate	2013	9–18	Low—(3.3 MBq/nmol) carrier-added	Mizuta et al. [28]