12180-80-2Relevant articles and documents
1-Ethyl-3-methylimidazolium halogenoaluminate ionic liquids as solvents for Friedel-Crafts acylation reactions of ferrocene
Stark, Annegret,MacLean, Bonnie L.,Singer, Robert D.
, p. 63 - 66 (1999)
Friedel-Crafts acylations of ferrocene in 1-ethyl-3-methylimidazolium halogenoaluminate ionic liquids, [emim]I-(AlCl3)x are described.3 The effect of varying the "bulk" Lewis acidity of the ionic liquids used as solvents in these reactions and the effect of varying the relative amounts of acylating agent with respect to the amount of ferrocene in these reactions is also described. The use of a variety of different acylating agents in our studies demonstrates the scope of this reaction performed in these ionic liquid systems.
Ruthenium-Catalyzed Enantioselective Hydrogenation of Ferrocenyl Ketones: A Synthetic Method for Chiral Ferrocenyl Alcohols
Lu, Bin,Wang, Qun,Zhao, Mengmeng,Xie, Xiaomin,Zhang, Zhaoguo
, p. 9563 - 9569 (2015/10/12)
Highly effective asymmetric hydrogenation of various ferrocenyl ketones, including aliphatic ferrocenyl ketones as well as the more challenging aryl ferrocenyl ketones, was realized in the presence of a Ru/diphosphine/diamine bifunctional catalytic system. Excellent enantioselectivities (up to 99.8% ee) and activities (S/C = 5000) could be obtained. These asymmetric hydrogenations provided a convenient and efficient synthetic method for chiral ferrocenyl alcohols, which are key intermediates for a variety of chiral ferrocenyl ligands and resolving reagents.
Acceptor-substituted ferrocenium salts as strong, single-electron oxidants: Synthesis, electrochemistry, theoretical investigations, and initial synthetic application
Khobragade, Dushant A.,Mahamulkar, Shraddha G.,Pospí?il, Lubomír,Císa?ová, Ivana,Rulí?ek, Lubomír,Jahn, Ullrich
supporting information, p. 12267 - 12277 (2012/11/14)
A series of mono- and 1,1'-diheteroatom-substituted ferrocene derivatives as well as acylated ferrocenes was prepared efficiently by a unified strategy that consists of selective mono- and 1,1'-dilithiation reactions and subsequent coupling with carbon, phosphorus, sulfur and halogen electrophiles. Chemical oxidation of the ferrocene derivatives by benzoquinone, 2,3-dichloro-5,6- dicyanobenzoquinone, AgPF6, or 2,2,6,6-tetramethyl-1-oxopiperidinium hexafluorophosphate provided the corresponding ferrocenium salts. The redox potentials of the synthesized ferrocenes were determined by cyclic voltammetry, and it was observed that all new ferrocenium salts have stronger oxidizing properties than standard ferrocenium hexafluorophosphate. An initial application of selected derivatives in an oxidative bicyclization revealed that they mediate the transformation under considerably milder conditions than ferrocenium hexafluorophosphate. Quantum chemical calculations of the reduction potentials of the substituted ferrocenium ions were carried out by using a standard thermodynamic cycle that involved the gas-phase energetics and solvation energies of the contributing species. A remarkable agreement between theory and experiment was found: the mean average deviation amounted to only 0.030-V and the maximum deviation to 0.1-V. This enabled the analysis of various physical contributions to the computed reduction potentials of these ferrocene derivatives, thereby providing insight into their electronic structure and physicochemical properties. Copyright
Asymmetric synthesis of planar chiral 2-mono- and 2,2′-disubstituted 1,1′-bisbenzoylferrocenes
Enders, Dieter,Klumpen, Thomas
, p. 698 - 709 (2007/10/03)
An efficient and flexible asymmetric synthesis of planar chiral 2-mono- and 2,2′-disubstituted 1,1′-bisbenzoylferrocenes 4 and 6 is reported. Key step is a highly diastereoselective ortho-metalation of 1,1′-bisbenzoylferrocene 1 via the corresponding bis-SAMP-hydrazone 2 (de≥96%), followed by trapping with various carbon, silicon, phosphorus and sulfur electrophiles. Cleavage of the monosubstituted hydrazones 3 led to monosubstituted ketones 4 (ee≥98%). Further ortho-substitution of the hydrazones 3 afforded 2,2′-disubstituted hydrazones 5, which could be cleaved to disubstituted ferrocenyl diketones 6 (ee≥99%). The new methodology allows a broad and flexible fine-tuning of ferrocenyl ligands desired in asymmetric catalysis. Ozonolysis or reductive hydrazone cleavage using TiCl3 or SnCl2 were the methods of choice to remove the auxiliary.
Efficient regio- and diastereo-controlled synthesis of 1,1′- and 1,1′,2,2′-functionalised ferrocenes and the formation of 2-oxa[3]ferrocenophanes
Carroll, Michael A.,White, Andrew J.P.,Widdowson, David A.,Williams, David J.
, p. 1551 - 1557 (2008/10/08)
The synthesis of a C2 symmetric 1,1′ ,2,2′-tetrasubstituted ferrocene system was discussed. The route involved the reduction of ferrocenyl carbonyl compounds which gave access to a range of alcohols, alkenes, alkanes, ethers, and 2-oxa[3]ferrocenophanes depending on the precise conditions used. The loss of optical activity of 1,1′-bis(hydroxymethyl)ferrocenes and 1,1′-bis(hydroxymethyl)ruthenocenes, which had been prepared by asymmetric reduction, was demonstrated in an acidic medium by extensive 1H NMR studies.
Accurate redeterminations of 1,1′-dibenzoylferrocene and (4-nitrophenyl)-ferrocene
Gallagher, John F.,Ferguson, George,Ahmed, S. Zaka,Glidewell, Christopher,Lewis, Arwel
, p. 1772 - 1775 (2008/10/09)
In the solid state, molecules of 1,1′-dibenzoylferrocene, [Fe(Cl12H9O)2], (I), are linked to form infinite chains in the [100] direction via (cyclopentadienyl)C - H...O hydrogen bonds [C...O 3.354 (4) A]. In the structure of (4-nitrophenyl)ferrocene, [Fe(C5H5)(C11H8NO2)], (II), there are no C - H-...O hydrogen bonds and molecules are separated by normal van der Waals distances. For earlier determinations see Struchkov [Dokl. Akad. Nauk SSSR (1956), 110, 67-70] for (I) and Roberts et al. [J. Chem. Soc. Dalton Trans. (1988), pp. 1549-1556] for (II).
A facile synthetic route to (η5-benzoylcyclopentadienyl)metal compounds
Jones, Stephen S.,Rausch, Marvin D.,Bitterwolf, Thomas E.
, p. 27 - 31 (2007/10/02)
A reaction between cyclopentadienylsodium and ethyl benzoate in refluxing THF produces (benzoylcyclopentadienyl)sodium (4) in 70-80percent yield.Subsequent treatment of 4 in ethanol solution with thallium ethoxide affords (benzoylcyclopentadienyl)thallium (3) in nearly quantitative yield.Reactions of 3 with Mn(CO)5Br, Re(CO)5Br, 2 or FeCl2 lead to the respective η5-benzoylcyclopentadienyl derivatives of these metals, and demonstrate the utility of 3 in organometallic syntheses.Reactions of several of these organometallic ketones with cymantrenyllithium5-C5H4Li)Mn(CO)3> provide a useful new route to bimetallic compounds.
