Unknown

Dataset Information

0

Sterically Stabilized Terminal Hydride of a Diiron Dithiolate.


ABSTRACT: The kinetically robust hydride [t-HFe2(Me2pdt)(CO)2(dppv)2]+ ([t-H1]+) (Me2pdt2- = Me2C(CH2S-)2; dppv = cis-1,2-C2H2(PPh2)2) and related derivatives were prepared with 57Fe enrichment for characterization by NMR, FT-IR, and NRVS. The experimental results were rationalized using DFT molecular modeling and spectral simulations. The spectroscopic analysis was aimed at supporting assignments of Fe-H vibrational spectra as they relate to recent measurements on [FeFe]-hydrogenase enzymes. The combination of bulky Me2pdt2- and dppv ligands stabilizes the terminal hydride with respect to its isomerization to the 5-16 kcal/mol more stable bridging hydride ([?-H1]+) with t1/2(313.3 K) = 19.3 min. In agreement with the nOe experiments, the calculations predict that one methyl group in [t-H1]+ interacts with the hydride with a computed CH···HFe distance of 1.7 Å. Although [t-H571]+ exhibits multiple NRVS features in the 720-800 cm-1 region containing the bending Fe-H modes, the deuterated [t-D571]+ sample exhibits a unique Fe-D/CO band at ?600 cm-1. In contrast, the NRVS spectra for [?-H571]+ exhibit weaker bands near 670-700 cm-1 produced by the Fe-H-Fe wagging modes coupled to Me2pdt2- and dppv motions.

SUBMITTER: Carlson MR 

PROVIDER: S-EPMC5821139 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

Similar Datasets

| S-EPMC3518320 | biostudies-literature
| S-EPMC5553979 | biostudies-literature
| S-EPMC5927630 | biostudies-literature
| S-EPMC8734113 | biostudies-literature
| S-EPMC5538135 | biostudies-literature
| S-EPMC8159291 | biostudies-literature
| S-EPMC5302539 | biostudies-literature
| S-EPMC4963924 | biostudies-literature
| S-EPMC3166632 | biostudies-literature
| S-EPMC5901669 | biostudies-literature