Synthesis of [³H] and [¹⁴C]genipin

Abstract

[3H]Genipin was synthesized in a single step by Ir(I) catalyzed hydrogen isotope exchange. Conditions for selective exchange of the sp2 CH bond ortho to the methyl ester functionality were developed through deuterium modeling studies through a catalyst screen. Optimized conditions so obtained were then utilized with tritium gas to generate [3H]genipin at a specific activity of 18.5 Ci/mmol. Racemic [14C]genipin was prepared in eight steps in overall 5.4% radiochemical yield from potassium [14C]cyanide.