Observing the Formation and the Reactivity of an Octahedral Iron(V) Nitrido Complex in Real Time

摘要

Molecular species containing iron at extraordinarily high oxidation states are considered as key catalytic centers in a number of important chemical and biochemical transformations. For example, a ferryl-oxo species, Fe~(IV) = O, is at the heart of the hydroxylation of hydrocarbons by oxygen-activating heme enzymes like cytochrome P-450. Similarly, oxoiron(IV) and oxoiron(V) intermediates have been invoked in the catalytic cycles of several non-heme enzymes including those catalyzing the conversion of methane into methanol or the dihydroxylation of aromatic compounds. This relevance to fundamental questions related to the enzymatic oxidation has fueled research devoted to the preparation and isolation of compounds containing highly oxidized iron centers, to studying their chemical reactivities, and to understanding their electronic structure by means of advanced spectroscopic and theoretical methods. Particularly intriguing high-valent iron compounds are those in which the iron forms multiple bonds to nitrogen because transition-metal nitrides may be implicated in the catalytic reduction of N2 to ammonia.