Protonation of a subsite analogue of [FeFe]-hydrogenase: mechanism of a deceptively simple reaction revealed by time-resolved IR spectroscopy

We provide the first detailed time-resolved mechanistic information on the protonation of a model of the subsite of [FeFe]-hydrogenase, [Fe-2(mu-pdt)(CO)(4)(PMe3)(2)]; the deceptively simple stoichiometric reaction is shown to be limited by the rate of protonation of the basal-apical isomer followed by its rearrangement to the transoid basal form.