Cyclopentadienyldicarbonyl(tetrahydrofuran)iron(II) tetrafluoroborate is a catalyst used in Lewis acid catalyzed reactions such as aziridination, cyclopropanation, and insertion reaction with diazo compounds, and the preparation of β-keto esters via Lewis acid-catalyzed addition of Et diazoacetate to arylaldehydes. Cyclopentadienyldicarbonyl(tetrahydrofuran)iron(II) tetrafluoroborate is also used in iron mediated nitrenoid transfer and the Diels-Alder reaction of dienes with enones.
