We report that a novel use of 35 GHz 1H-ENDOR spectroscopy establishes the presence in 1 of an Fe IV-O⋯H-O-Fe III hydrogen bond predicted by density functional theory computations to generate a six-membered-ring core for 1. The hydrogen bond rationalizes the difference in the C-H bond cleavage reactivity between 1 and 4 (OCH 3) (where a CH 3O group has replaced the HO on the Fe III site). This result substantiates the seemingly paradoxical conclusion that the nonheme Fe IV-O unit of 1 not only has the electrophilic character required for H-atom abstraction but also retains sufficient nucleophilic character to accept a hydrogen bond from the Fe III-OH unit.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry