Fe-Catalyzed Phenanthrene Synthesis via [4+2] Benzannulation

The reactant depicted in the Scheme should be a biaryl or 2-alkenylphenyl Grignard reagent, and not a biphenyl of 2-alkenylbenzene. Further, the structure of the ligand, 4,4′-di-tert-butyl-2,2′-bipyridyl (dtbpy) was wrong. The corrected Scheme is shown below. We apologize for these mistakes.