Zhao Qunchao, Etersque Jean M, Lu Shuiyu, Telu Sanjay, Pike Victor W
Molecular Imaging Branch, National Institute of Mental Health, Building 10, Room B3C346, 10 Center Drive, Bethesda, Maryland 20892, United States.
Org Lett. 2023 Dec 8;25(48):8650-8654. doi: 10.1021/acs.orglett.3c03499. Epub 2023 Nov 27.
Aryliodonium precursors are widely applied for copper-free labeling of positron emission tomography (PET) tracers with fluorine-18. We assessed F-fluoroarene regioisomer formation in examples of these labeling methods. Aryliodonium ylides derived from Meldrum's acid bearing electron-donating groups react with [F]fluoride in acetonitrile to produce regioisomeric F-fluoroarenes via a competing aryne pathway. Regioisomer formation is decreased or absent in DMF. Analytically checking for the absence of the F-regioisomer from any particular PET tracer radiosynthesis using these or similar methods is recommended.
芳基碘鎓前体被广泛应用于用氟 - 18对正电子发射断层扫描(PET)示踪剂进行无铜标记。我们评估了这些标记方法实例中氟 - 氟代芳烃区域异构体的形成。源自带有供电子基团的丙二酸亚异丙酯的芳基碘鎓叶立德在乙腈中与[F]氟化物反应,通过竞争的芳炔途径生成区域异构体氟 - 氟代芳烃。在N,N - 二甲基甲酰胺(DMF)中区域异构体的形成减少或不存在。建议使用这些或类似方法对任何特定PET示踪剂放射性合成中氟区域异构体的缺失进行分析检查。