Fast and efficient copper-mediated 18F-fluorination of arylstannanes, aryl boronic acids, and aryl boronic esters without azeotropic drying




Salla Orvokki Lahdenpohja, Noora Annika Rajala, Johan Rajander, Anna Kaarina Kirjavainen

PublisherSpringer Internat. Publ.

2019

EJNMMI Radiopharmacy and Chemistry

28 (2019)

4

2365-421X

DOIhttps://doi.org/10.1186/s41181-019-0079-y

https://research.utu.fi/converis/portal/detail/Publication/44982789



Background

Copper-mediated radiofluorination is a straightforward method to produce a variety of [18F]fluoroarenes and [18F]fluoroheteroarenes. To minimize the number of steps in the production of 18F-labelled radiopharmaceuticals, we have developed a short and efficient azeotropic drying-free 18F-labelling
method using copper-mediated fluorination. Our goal was to improve the
copper-mediated method to achieve wide substrate scope with good
radiochemical yields with short synthesis time.

Results

Solid phase extraction with Cu (OTf)2 in dimethylacetamide is a suitable activation method for [18F]fluoride. Elution efficiency with Cu (OTf)2
is up to 79% and radiochemical yield (RCY) of a variety of model
molecules in the crude reaction mixture has reached over 90%. Clinically
relevant molecules, norepinephrine transporter tracer [18F]NS12137 and monoamine transporter tracer [18F]CFT were produced with 16.5% RCY in 98 min and 5.3% RCY in 64 min, respectively.

Conclusions

Cu (OTf)2 is a suitable elution agent for releasing [18F]fluoride
from an anion exchange cartridge. The method is fast and efficient and
the Cu-complex is customizable after the release of [18F]fluoride. Alterations in the [18F]fluoride
elution techniques did not have a negative effect on the subsequent
labelling reactions. We anticipate this improved [18F]fluoride elution technique to supplant the traditional azeotropic drying of [18F]fluoride in the long run and to concurrently enable the variations of the copper-complex.


Last updated on 2024-26-11 at 19:59