<p>Palladium-promoted reactions have been employed for the synthesis of compounds labelled with <sup>11</sup>C (t<sub>½</sub> = 20.3 min). The precursor [<sup>11</sup>C]methyl iodide was used in palladium-promoted cross-coupling reactions with organostannanes. With this method, large molecules with several functional groups, that is prostacyclin analogues, have been synthesised in up to 54 % decay-corrected radiochemical yield, calculated from [<sup>11</sup>C]methyl iodide. However, since this method did not afford reproducible yields, a second method where copper(I) was used as a co-catalyst with palladium, was developed. In the second method, a lower reaction temperature could be used and more reproducible yields were obtained. Employing this method, a prostaglandin analogue was synthesised in 34 % decay-corrected radiochemical yield calculated from [<sup>11</sup>C]methyl iodide. The total synthesis time was 30 min and the radiochemical purity was higher than 95 %. The specific radioactivity of the compounds obtained with these two methods was approximately 100 GBq/μmol.</p><p><sup>11</sup>C-Labelled aliphatic and aromatic alkenes were synthesised from [<sup>11</sup>C]methyl iodide in a Wittig olefination reaction using a published method. The <sup>11</sup>C-labelled alkenes were reacted with five aromatic halidein Heck coupling reactions, producing five [<sup>11</sup>C]stilbene analogues in 34-40 % decay-corrected radiochemical yield. The radiochemical purity was higher than 95 % and the total synthesis timwas 40 min. </p><p><sup>11</sup>C-Labelled alkenes were also synthesised from <sup>11</sup>C-labelled aldehydes. The <sup>11</sup>C-labelled aldehydes were obtained from [<sup>11</sup>C]carbon monoxide in a palladium-mediated formylation of aryl iodides in 51-87 % radiochemical yield, determined by analytical LC and corrected for trappinefficiency. A range of palladium catalysts and hydride reagents were investigated. The labelled aldehydes were used in a subsequent Wittig olefination reaction where various Wittig salts were employed tsynthesise a variety of alkenes. The radiochemical yields were 30-76 %, determined by analytical LC.</p>
| Identifer | oai:union.ndltd.org:UPSALLA/oai:DiVA.org:uu-1071 |
| Date | January 2000 |
| Creators | Björkman, Margareta |
| Publisher | Uppsala University, Department of Chemistry, Uppsala : Acta Universitatis Upsaliensis |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Doctoral thesis, comprehensive summary, text |
| Relation | Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, 1104-232X ; 564 |
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