| Abstract
| - Lithiation of (S)-N-(1-phenylpropyl)-2-phenylquinoline-4-carboxamide with the complex n-BuLi/TMEDA(1/1 molar ratio) in THF at −60 °C for 5 h occurred selectively at the position 3 of the quinoline ring.This selectivity was shown by the absence of racemization of the stereogenic center and the formationof the corresponding functionalized quinolines in 59−74% yield by subsequent reaction with an electrophileat −60 °C for 1 h. The 3-trimethylstannyl derivative was subjected to a Stille reaction using methyl,phenyl, or thienyliodide to afford the alkyl or aryl quinolines in moderate to good yields. This methodologywas successfully applied to the radiosynthesis of [11C]SB 222200 using methyl iodide labeled with carbon-11 (β+ emitter, t1/2 = 20.4 min) for the in vivo study of NK-3 receptor by positron emission tomography(48−58% radiochemical yields from [11C]CH3I, decay corrected, 45 min total synthesis time).
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