A Solely Fe‐Catalyzed Sonogashira‐Type Coupling of non‐Activated Secondary Alkyl Iodides with Terminal Alkynes

Abstract

An iron‐catalyzed Sonogashira coupling of non‐activated secondary alkyl iodides with terminal alkynes is described. The reaction proceeds under mild conditions in N‐MethylPyrrolidone without auxiliary ligand or co‐catalyst. This procedure allowed the obtention of 28 coupling products. Moreover, slow addition of LiHMDS base allows to achieve up to 89% yields. This method enables the conversion of non‐activated alkyl iodides in a Fe‐catalyzed Sonogashira‐type cross‐coupling, which was so far not achievable with iron catalysts. Preliminary mechanistic studies suggest the implication of a key single electron transfer in the catalytic process.