Radiosynthesis of 1-iodo-2-[11 C]methylpropane and 2-methyl-1-[11 C]propanol and its application for alkylation reactions and C-C bond formation

J Labelled Comp Radiopharm. 2017 Oct;60(12):566-576. doi: 10.1002/jlcr.3536. Epub 2017 Sep 26.

Abstract

The multitude of biologically active compounds requires the availability of a broad spectrum of radiolabeled synthons for the development of positron emission tomography (PET) tracers. The aim of this study was to synthesize 1-iodo-2-[11 C]methylpropane and 2-methyl-1-[11 C]propanol and investigate the use of these reagents in further radiosynthesis reactions. 2-Methyl-1-[11 C]propanol was obtained with an average radiochemical yield of 46 ± 6% d.c. and used with fluorobenzene as starting material. High conversion rates of 85 ± 4% d.c. could be observed with HPLC, but large precursor amounts (32 mg, 333 μmol) were needed. 1-Iodo-2-[11 C]methylpropane was synthesized with a radiochemical yield of 25 ± 7% d.c. and with a radiochemical purity of 78 ± 7% d.c. The labelling agent 1-iodo-2-[11 C]methylpropane was coupled to thiophenol, phenol and phenylmagnesium bromide. Average radiochemical conversions of 83% d.c. for thiophenol, 40% d.c. for phenol, and 60% d.c. for phenylmagnesium bromide were obtained. In addition, [11 C]2-methyl-1-propyl phenyl sulphide was isolated with a radiochemical yield of 5 ± 1% d.c. and a molar activity of 346 ± 113 GBq/μmol at the end of synthesis. Altogether, the syntheses of 1-iodo-2-[11 C]methylpropane and 2-methyl-1-[11 C]propanol were achieved and applied as proof of their applicability.

Keywords: 1-iodo-2-[11C]methylpropane; 2-methyl-1-[11C]propanol; [11C]alkylation; [11C]etherification; carbon-11 radiolabelling; positron emission tomography.

MeSH terms

  • 1-Propanol / chemical synthesis*
  • 1-Propanol / chemistry*
  • Alkylation
  • Iodine Radioisotopes / chemistry*
  • Isotope Labeling
  • Positron-Emission Tomography
  • Propane / chemical synthesis*
  • Propane / chemistry*
  • Radiochemistry

Substances

  • Iodine Radioisotopes
  • 1-Propanol
  • Propane