AI Article Synopsis
- The study investigates the reaction of five-coordinate Fe(NS) complexes with a one-electron oxidant and base, leading to the formation of Fe(iminobenzenethiolate) complexes through hydrogen atom loss.
- Characterization techniques like single-crystal XRD and various spectroscopies reveal that these new complexes have a ground state of 3/2 and show that, without a base, the oxidation process leads to disulfide formation rather than direct oxidation.
- The research highlights the interconversion between Fe(aminobenzenethiolate) and Fe(iminobenzenethiolate) forms through proton-coupled electron transfer, providing insight into the bond dissociation free energy for the N-H bond and the influence of protonation
Article Abstract
Reaction of the five-coordinate Fe(NS) complexes, [Fe(iPrTACN)(abt)](OTf) (abt = aminobenzenethiolate, X = H, CF), with a one-electron oxidant and an appropriate base leads to net H atom loss, generating new Fe(iminobenzenethiolate) complexes that were characterized by single-crystal X-ray diffraction (XRD), as well as UV-vis, EPR, and Mössbauer spectroscopies. The spectroscopic data indicate that the iminobenzenethiolate complexes have = 3/2 ground states. In the absence of a base, oxidation of the Fe(abt) complexes leads to disulfide formation instead of oxidation at the metal center. Bracketing studies with separated proton-coupled electron-transfer (PCET) reagents show that the Fe(aminobenzenethiolate) and Fe(iminobenzenethiolate) forms are readily interconvertible by H/e transfer and provide a measure of the bond dissociation free energy (BDFE) for the coordinated N-H bond between 64 and 69 kcal mol. This work shows that coordination to the iron center causes a dramatic weakening of the N-H bond and that Fe- versus S-oxidation in a nonheme iron complex can be controlled by the protonation state of an ancillary amino donor.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8139613 | PMC |
| http://dx.doi.org/10.1021/acs.inorgchem.0c03779 | DOI Listing |
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