Palladium-mediated 11 C-carbonylations using aryl halides and cyanamide.

A robust and high-yielding radiochemical synthesis of ¹¹ C-N-cyanobenzamides using a palladium-mediated aminocarbonylation with ¹¹ C-CO, aryl halides and cyanamide is described. The bidentate ligand 1,1'-bis(diphenylphosphino)ferrocene provided ¹¹ C-N-cyanobenzamides from aryl-iodides, bromides, triflates and even chlorides in 28-79% radiochemical yield after semi-preparative HPLC. To further highlight the utility of this method, novel ¹¹ C-N-cyanobenzamide analogs of flufenamic acid, meflanamic acid, dazoxiben and tamibarotene were synthesized in 34-71% radiochemical yields.