206429-07-4

Upstream product

• 1541-10-2 mesitylthiol 
• 39393-88-9 μ-oxo-bis[(2,3,7,8,12,13,17,18-octaethylporphyrinato)iron(III)] 
• 1483-92-7 bis(2,4,6-trimethylphenyl)disulfide 

Relevant academic research and scientific papers

Axial thiophenolate coordination on diiron(III)bisporphyrin: Influence of heme-heme interactions on structure, function and electrochemical properties of the individual heme center

The binding of a series of substituted thiophenols as axial ligands on a highly flexible ethane-bridged diiron(III)bisporphyrin framework has been investigated as a model of diheme proteins. Spectroscopic characterization reveals a high-spin (S = 5/2) state of iron for all of the pentacoordinate thiophenolato complexes. In the UV-visible spectra of the complexes, the positions of the Soret and band I have been found to be dependent on the pKa of thiophenols. The alternating shift pattern, which has opposite sign of the chemical shifts for meta- vs. ortho- and para- protons in the 1H NMR spectra, is attributed to negative and positive spin densities, respectively, on thiophenolate carbon atoms and is indicative of π-spin delocalization to the bound thiophenolate ligand. The Fe(III)/Fe(II) redox couple of the complexes bears a linear relationship with the pKa of thiophenol and is found to be positively shifted with decreasing pKa. The effect of the electronic nature of the substituent on the thiophenolate ring has also been demonstrated in which a large potential range of 540 mV was observed (in contrast to the value of only 270 mV in case of monoheme analogues) for the Fe(III)/Fe(II) redox couple on going from monoheme to diheme and is attributed to the interheme interaction. Also, the Fe(III)/Fe(II) redox potential of the thiophenolato complexes has been found to be more positively shifted compared to their phenolato analogues, which was further supported by DFT calculation. The addition of another thiophenol at the sixth axial position of the five-coordinate thiophenolato complex causes a change in iron spin from high (S = 5/2) to low (S = 1/2) along with a large positive shift of 490 mV for the Fe(III)/Fe(II) redox couple.

Synthesis and Properties of Octaethylporphinato(arenethiolato)iron(III) Complexes with Intramolecular NH···S Hydrogen Bond: Chemical Function of the Hydrogen Bond

Iron(III) porphinate complexes of arenethiolate having single or double NH···S hydrogen bonds at the axial position, [FeIII(OEP){S-2,6-(RCONH)2C6H3}] (R = CF3 (1), CH3 (2)) or [FeIII(OEP)(S-2-RCONHC6H4)] (R = CF3 (3), CH3 (4), t-Bu (5)), were synthesized as models of P-450 and chloroperoxidase. The presence of an NH···S hydrogen bond in these complexes is confirmed by their crystal structures in the solid state, the IR shift of the amide NH band and the direct through-bond contact-shift of the amide 2H NMR signal in benzene. The NH···S hydrogen bond elongates the Fe-S bond distance, stabilizes the Fe(III) state, protects the complexes from decomposition by air and moisture, and shifts the redox to more positive potentials. These functions by the hydrogen bond are more significant than the effect of steric hindrance.