A mild, rapid synthesis of freebase [11C]nicotine from [11C]methyl triflate

A rapid, mild radiosynthesis of freebase [11C]nicotine was developed by the methylation of freebase nornicotine with [11C]methyl triflate in acetone (5 min, 45 °C). A basic (pH 10.5-11.0) HPLC system reproducibly yielded freebase [11C]nicotine as a well-defined single peak. The freebase [11C]nicotine was concentrated by solid phase extraction and formulated in 50 µL ethanol (370 MBq/50 µL) without evaporative loss suitable for a cigarette spiking study. A radiochemical yield of 60.4±4.7% (n=3), radiochemical purity ≥99.9% and specific activity of 648 GBq/µmol at EOB for 5 min beams were achieved.