title: A thiolate-ligated nonheme oxoiron(IV) complex relevant to cytochrome P450.
abstract: Thiolate-ligated oxoiron(IV) centers are postulated to be the key oxidants in the catalytic cycles of oxygen-activating cytochrome P450 and related enzymes. Despite considerable synthetic efforts, chemists have not succeeded in preparing an appropriate model complex. Here we report the synthesis and spectroscopic characterization of [FeIV(O)(TMCS)]+ where TMCS is a pentadentate ligand that provides a square pyramidal N4(SR)apical, where SR is thiolate, ligand environment about the iron center, which is similar to that of cytochrome P450. The rigidity of the ligand framework stabilizes the thiolate in an oxidizing environment. Reactivity studies suggest that thiolate coordination favors hydrogen-atom abstraction chemistry over oxygen-atom transfer pathways in the presence of reducing substrates.
authors.affiliation: Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, MN 55455, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bukowski
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Koehntop
authors.forename: Audria
authors.initials: A
authors.lastname: Stubna
authors.forename: Emile L
authors.initials: EL
authors.lastname: Bominaar
authors.forename: Jason A
authors.initials: JA
authors.lastname: Halfen
authors.forename: Eckard
authors.initials: E
authors.lastname: Münck
authors.forename: Wonwoo
authors.initials: W
authors.lastname: Nam
authors.forename: Lawrence
authors.initials: L
authors.lastname: Que
mesh_terms: D002384:Catalysis; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry* / Q000378:metabolism*; D006859:Hydrogen / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D008024:Ligands; D015394:Molecular Structure; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D015204:Spectroscopy, Mossbauer; D013057:Spectrum Analysis; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013455:Sulfur / Q000737:chemistry*; D013696:Temperature; D014965:X-Rays
chemical_list: C505853:(FeIV(O)(TMCS))+; D008024:Ligands; D016877:Oxidants; D013438:Sulfhydryl Compounds; D013455:Sulfur; D006859:Hydrogen; D003577:Cytochrome P-450 Enzyme System; D007501:Iron; D010100:Oxygen