Straightforward preparation of labeled potassium cyanate by ozonation and application to the synthesis of [ 13 C] or [ 14 C]ureidocarboxylic acids

The development of new efficient syntheses of labeled reagents is a great challenge. Avoidance of overcomplicated procedures, availability and cost of starting materials are important considerations in choosing the synthetic route. In this report, we describe a facile and rapid preparation of labeled cyanate by ozonation of cyanide, a basic precursor. The crude cyanate was used without purification for the synthesis of various [ 13 C] or [ 14 C]ureidocarboxylic acids (20‐68% yield from potassium cyanide). According to these results, cyanide ozonation may prove to be a promising alternative to traditional preparations of labeled cyanate.