Chemoselective Kumada‐Type Iron Catalysis with Alkyl Grignard Reagents: Reductive Cyclization and Cyclomethylation

Abstract

A chemoselective reductive cyclization and cyclomethylation reaction of 7‐iodohept‐2‐yne and 7‐iodohepta‐1,2‐diene derivatives has been carried out using an iron catalyst and various alkyl Grignard reagents, resulting in the formation of pyrrolidines, tetrahydrofurans, and carbocycles with an alkene functional group. The reaction is initiated by single‐electron transfer from reduced Fe species to alkyl iodides and the resulting Fe−H or Fe−Me compound differentiated the structures of the cyclized products, which exhibited diverse complexities and synthetic utilities.