Open Collections

Radiolabelling of organic molecules with short-lived radionuclides (¹¹C, ¹⁸F)

University of British Columbia

The primary aim of this study was to develop new methods for the introduction of short-lived radionuclides(11C, 18F) into organic molecules. This was accomplished by the use of organometallic intermediates: (i)(η6-arene)tricarbonylchromium complexes were used to facilitate aromatic nucleophilic substitution of the attached arene for the incorporation of [11C]cyanide anion, and (ii) vinyl-tin derivatives were employed for electrophilic fluorination reactions to produce 19F- and18F-labelled vinyl fluorides. A range of simple(η6-arene)tricarbonylchromium complexes were prepared as model systems. Fluorine was found to be the only leaving group that was readily displaced by cyanide. Non-radioactive and11C-labelled aryl nitriles were prepared in 10 minutes by reaction of complexes 1, 4, 5, and 6 with[12C]cyanide and[11C]cyanide in DMSO at elevated temperature. Under the reaction conditions used, the aryl nitrile product was liberated from the chromium tricarbonyl moiety thereby obviating the need for a separate oxidative decomplexation step. The reactivity of (E)-vinylstannanes 30, 31, 32, 33, and 34 was studied with elemental fluorine and acetyl hypofluorite under varied conditions. Generally, gaseous CH3COOF was found to be the most effective fluorinating agent for the electrophilic cleavage of vinyl-tin bonds. For example, 31 was fluorinated with CH3COOF, at room temperature, to yield an isomeric mixture of 39 and 40 in 41-42% yield; fluorination with F2 proceeded in 9.0% yield at best. Subsequently, 31 was radiofluorinated with CH3COO18F in 19% radiochemical yield (based on starting [18F]F2). [Scientific formulae used in this abstract could not be reproduced. Abstract also includes a figure.]

Thesis/Dissertation

application/pdf

2009-06-04

For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.

http://hdl.handle.net/2429/8741

Chemistry

University of British Columbia

UBCV

DSpace