Synthesis and Analysis of Carbon-14 Labelled Imidacloprid With High Specific Activity

A version of carbon-14 labelled imidacloprid, (E)-N-(1-((6-chloropyridin-3-yl)［¹⁴C］methyl)imidazolidin-2-ylidene)nitramide (1 354.2 MBq), was synthesized from barium-［¹⁴C］carbonate via Grignard reaction, reduction, bromination, nucleophilic substitution reaction and purified by preparative HPLC with the overall yield of 51%. The labelled product was identified by using ESI-MS and ¹H NMR. Its radiochemical and chemical purity are more than 98%, determined by TLC-IIA, HPLC-LSC, HPLC-FSA, and HPLC-PDA, respectively. The specific activity of the product is 1 871.46 GBq/mol. This product can be used as radiotracer in the study of the directional accumulation and metabolism of imidac-loprid in plants.