Functional Model of Compound II of Cytochrome P450: Spectroscopic Characterization and Reactivity Studies of a Fe-OH Complex.

Herein, we show that the reaction of a mononuclear Fe(OH) complex () with -tosyliminobenzyliodinane (PhINTs) resulted in the formation of a Fe(OH) species (). The obtained complex was characterized by an array of spectroscopic techniques and represented a rare example of a synthetic Fe(OH) complex. The reaction of with the one-electron oxidizing agent was reported to form a ligand-oxidized Fe(OH) complex (). revealed a one-electron reduction potential of -0.22 V vs Fc/Fc at -15 °C, which was 150 mV anodically shifted than ( = -0.37 V vs Fc/Fc at -15 °C), inferring to be more oxidizing than . reacted spontaneously with (4-OMe-CH)C to form (4-OMe-CH)C(OH) through rebound of the OH group and displayed significantly faster reactivity than . Further, activation of the hydrocarbon C-H and the phenolic O-H bond by and was compared and showed that is a stronger oxidant than . A detailed kinetic study established the occurrence of a concerted proton-electron transfer/hydrogen atom transfer reaction of . Studying one-electron reduction of and using decamethylferrocene (Fc*) revealed a higher of than . The study established that the primary coordination sphere around Fe and the redox state of the metal center is very crucial in controlling the reactivity of high-valent Fe-OH complexes. Further, a Fe(OMe) complex () was synthesized and thoroughly characterized, including X-ray structure determination. The reaction of with PhINTs resulted in the formation of a Fe(OMe) species (), revealing the presence of two Fe species with isomer shifts of -0.11 mm/s and = 0.17 mm/s in the Mössbauer spectrum and showed Fe/Fe potential at -0.36 V vs Fc/Fc couple in acetonitrile at -15 °C. The reactivity studies of were investigated and compared with the Fe(OH) complex ().