Mechanism of Reduction of Ferric Porphyrins by Sulfide: Identification of a Low Spin FeIII-SH Intermediate.
Kaustuv MittraAsmita SinghaAbhishek DeyPublished in: Inorganic chemistry (2017)
The reaction of FeIII porphyrin complexes bearing distal hydrogen bonding residues with sulfide/hydrosulfide is kinetically monitored to reveal the presence of an intermediate and a kH/kD of 3.0. This intermediate is trapped at low temperatures and investigated with resonance Raman and electron paramagnetic resonance spectroscopy. The results, corroborated by density functional theory calculations, indicate that this species is a six-coordinate low spin hydrosulfide bound ferric porphyrin. The homolytic cleavage of the FeIII-SH bond resulting in the formation of a ferrous porphyrin and hydrosulfide radical (trapped with 5,5-dimethyl-1-pyrrilone-N-oxide) is found to be the overall rate-determining step of the reaction.
Keyphrases
- density functional theory
- energy transfer
- electron transfer
- molecular dynamics
- photodynamic therapy
- metal organic framework
- quantum dots
- single molecule
- high resolution
- iron deficiency
- atomic force microscopy
- genome wide
- dna binding
- gene expression
- room temperature
- transcription factor
- transition metal
- molecular dynamics simulations
- dna methylation