Ferrole

{{Short description|Class of chemical compounds}} thumb|Structure of the ferrole Fe₂C₄H₄(CO)₆.<ref>{{cite journal|doi=10.1016/S0022-328X(00)82143-9|title=Kristallstruktur, ¹H-NMR- und Massenspektrum von Tricarbonylferracyclopentadien-tricarbonyleisen, C₄H₄Fe₂(CO)₆|year=1976|last1=Dettlaf|first1=Gerd|last2=Weiss|first2=Erwin|journal=Journal of Organometallic Chemistry|volume=108|issue=2|pages=213–223}}</ref> Color scheme: red = O, gray = C, dark blue = Fe, white = H. {{confuse| Ferrule}} In organoiron chemistry, a '''ferrole''' is a type of diiron complex containing the (OC)₃FeC₄R₄ heterocycle that is pi-bonded to a Fe(CO)₃ group. These compounds have Fe-Fe bonds (ca. 252 pm) and semi-bridging CO ligands (Fe-C distances = 178, 251 pm). They are typically air-stable, soluble in nonpolar solvents, and red-orange in color.<ref>{{cite book|doi=10.1016/B978-008046518-0.00051-9|chapter=Dinuclear Iron Compounds with Hydrocarbon Ligands|title=Comprehensive Organometallic Chemistry|year=1982|last1=Fehlhammer|first1=W.P.|last2=Stolzenberg|first2=H.|pages=513–613|isbn=9780080465180|editor1=Geoffrey Wilkinson|editor2=F. Gordon A. Stone|editor3=Edward W. Abel}}</ref> ==Synthesis== Ferroles typically arise by the reaction of alkynes with iron carbonyls. Such reactions are known to generate many products, e.g. complexes of cyclopentadienones and para-quinones.<ref>{{cite book|title=Organic Syntheses via Metal Carbonyls Volume 1|year=1968|editor1=Piero Pino|editor2=Irving Wender|publisher=Wiley Interscience|location=NY}}</ref><ref>{{cite journal |doi=10.1021/cr60218a001|title=Synthesis of Organic Compounds by Direct Carbonylation Reactions Using Metal Carbonyls |year=1962 |last1=Bird |first1=C. W. |journal=Chemical Reviews |volume=62 |issue=4 |pages=283–302 }}</ref>

Another route involves the desulfurization of thiophenes (SC₄R₄) by iron carbonyls, shown in the following idealized equation: :Fe₃(CO)₁₂ + SC₄R₄ → Fe₂(CO)₆C₄R₄ + FeS + 6{{nbsp}}CO

An unusual route to ferroles involves treatment of Collman's reagent with trimethylsilyl chloride (tms = (CH₃)₃Si): :2{{nbsp}}Na₂Fe(CO)₄ + 4{{nbsp}}tmsCl → Fe₂(CO)₆C₄(Otms)₄ + 2{{nbsp}}CO + 4{{nbsp}}NaCl

==Reactions== Some ferroles react with tertiary phosphines to give the substituted flyover complex Fe₂(CO)₅(PR₃)(C₄R₄CO).<ref>{{cite journal |doi=10.1016/0022-328X(95)05936-J|title=Reactions of the 'ferrole' complex [Fe2(CO)6(C2Et2)2] with group 15 donor ligands and with alkynes. Stepwise formation and disengagement of tropones. Crystal and molecular structure of [Fe2(CO)5{(CEt)2 CO(CEt)2 CHCPH}]|year=1996|last1=Giordano|first1=Roberto|last2=Sappa|first2=Enrico|last3=Cauzzi|first3=Daniele|last4=Predieri|first4=Giovanni|last5=Tiripicchio|first5=Antonio|journal=Journal of Organometallic Chemistry|volume=511|issue=1–2|pages=263–271}}</ref><ref>{{cite book |doi=10.1016/B978-008046519-7.00058-7|chapter=Dinuclear Iron Compounds with Hydrocarbon Ligands|title=Comprehensive Organometallic Chemistry II|year=1995|last1=Fagan|first1=Paul J.|pages=231–258|isbn=9780080465197}}</ref>

==References== <references />

Category:Organoiron compounds Category:Carbonyl complexes Category:Trimethylsilyl compounds