Pesticides labelled with 14 C. II. Synthesis of propiconazole labelled in three different positions

Propiconazole was labelled with 14 C in three different positions: in the benzene ring, in the position 5 of the dioxolane ring, and in the triazole ring. The synthesis of three new key intermediates [(m‐dichloro[U‐ 14 C]benzene], 1,2,4‐[U‐ 14 C]triazole, [1‐ 14 C]‐pentane‐1,2‐diol) were also elaborated.