Room-temperature alkyne-nitrile metathesis and unambiguous proof for the existence of a high-valent iron-nitrido dication in the gas phase

An unprecedented alkyne-nitrile metathesis takes place when the high=valent iron-nitrido dication [Fe(L)N](2), with L=2.6-bis(2-methyl-1,3-diaminopropan-2-yl)pyridine, is reacted with alkynes in the gas pahse under thermal conditions. While the detailes role of the alkyne substrate with respect to relative rates, regioselectivities, and branching ratios remains to be elucidated, the very existence of this novel metathesis reaction provides additional experimental evidence of a genuine, long-lived, formal iron(V)-nitrido dication.