Bis(acetylacetonato)iron(II) is a coordination complex with the formula [Fe(C5H7O2)2]2. It is a dark, nearly black, air-sensitive, sublimable solid. It can be prepared by treating ferrous salts with 2,4-pentanedione in presence of base.Manríquez, J. M., Bunel, E. E., Oelckers, B., Román, E., Vv́squez, C., & Miller, J. S. (2007). Bis(2,4-Pentanedionato)Iron(II) [Iron(II) Bis(Acetylacetonate)]. Inorganic Syntheses, 267–269.
Structure
The structure of the complex has been confirmed by X-ray crystallography. As found for some other bis(acetylacetonates) (e.g., the nickel(II) and cobalt(II) derivatives), bis(acetylacetonato)iron(II) is not a monomer. It contains two Fe centers, one octahedral and one pentacoordinate. Three of the acetylacetonato ligands bridge the two Fe centers.
Reactions The dimeric structure of bis(acetylacetonato)iron(II) is readily cleaved by Lewis bases to give adducts Fe(C5H7O2)2L2. Examples include the dihydrate and the tmeda complex.
Bis(acetylacetonato)iron(II) is used as an anhydrous, "organic soluble" source of Fe(II). For example, it reacts with lithium bis(hydropentalenyl)iron to afford green [(C8H7)Fe]2-[(C8H8)2Fe], a quadruple-decker complex.Oelckers, B., Chavez, I., Manriquez, J. M., & Roman, E. (1993). On the way to delocalized organometallic polymers: triple- and quadruple-decker pentalene complexes of iron and cobalt. Organometallics, 12(9), 3396–3397. It also reacts with Li2Pn*(TMEDA)x (Pn* = permethylpentalene) to yield purple-black Fe2Pn*2.Binding, S. C., Green, J. C., Myers, W. K., & O’Hare, D. (2015). Synthesis, Structure, and Bonding for Bis(permethylpentalene)diiron. Inorganic Chemistry, 54(24), 11935–11940.
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