Effects of reaction conditions on rates of incorporation of no-carrier added F-18 fluoride into several organic compounds
✍ Scribed by Ml Korguth; Tr Degrado; Je Holden; Sj Gatley
- Publisher
- John Wiley and Sons
- Year
- 1988
- Tongue
- French
- Weight
- 559 KB
- Volume
- 25
- Category
- Article
- ISSN
- 0022-2135
No coin nor oath required. For personal study only.
✦ Synopsis
Apparent rate constants (fractional incorporation per minute per mole of organic reactant) were determined for reaction of no-carrier added F-18 fluoride with several aliphatic and aromatic substrates in acetonitrile or DMSO. No large differences were seen between tetraethylammonium and potassium Kryptofii-2,2,2 as supporting cation. Three hexose derivatives with triflate or cyclic sulfate leaving groups all gave apparent rate constants (obtained by dividing fractional incorporation by time in minutes and by molar concentration of reactant) near 0.4 at 23O and 5 at So. An aliphatic iodide reacted ten times more slowly. Aromatic substrates tested showed a wide range of rate constants from >SO at 23O (isotope exchange in 2,4-dinitrofluorobenzene) to 0.6 at 134O (p-nitroacetophenone).