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The reaction of diphenylphosphinoferrocene and 1,1'-bis(diphenylphosphino)ferrocene with (1:1 and 1:2 molar ration respectively) yields the monoadducts > 1 and 2> 2.By thermal treatment of 1 in refluxing toluene-acetic acid (10:3) the monometallated product Fe(C5H5)>(HO2CMe)2> 3 was obtained in practically quantitative yield.Compound 3 reacts with (1:1 molar ratio) giving the adduct Fe(C5H5)>> 4, which reacts thermally in toluene-acetic acid (10:3) yielding the doubly metallated product Fe(C5H5)>2(HO2CMe)2> 5 as a mixture of conformational isomers.An X-ray determination of 5 has been carried out: space group Pbca (orthorhombic), a = 18.065(3), b = 20.606(4), c = 26.242(5) Angstroem, Z = 8, and R = 0.038.The crystal structure shows that the two metallated phosphines are in a head-to-tail configuration.Thermal treatment of a mixture of and Fe(C5H4PPh2)2> (1:1 molar ratio) in acetic acid yields the compound 2Fe>(HO2CMe)>*CH2Cl2 6 after purification and crystallization from a CH2Cl2-hexane-acetic acid mixture.An X-ray diffraction investigation showed that this compound crystallizes in space group P21/c (monoclinic) with a = 12.735(4), b = 16.811(5), c = 20.161(8) Angstroem, β = 95.17(4) deg, Z = 4 and R = 0.089.The two PPh2 fragments of the ferrocene ligand act as bridging orthometallated ligands in a head-to-head configuration.Two well defined oxidation processes were detected by cyclic voltammetry for all the complexes in CH2Cl2 solution: the first one, in the range 0.6-0.7 V, is due to the couple Fe2+-Fe3+ while the second one, in the range 0.9-1.32 V, is due to the couple Rh24+-Rh25+.

The benefit of combining both a Lewis acid and a Lewis base in a catalytic system has been established for the hydroboration of CO2, using ferrocene-based phosphine, borane and phosphino-borane derivatives.

While 1,1′-bis(diphenylphosphino)ferrocene (dppf) is widely used as a ligand in coordination chemistry and catalysis, its congeners with oxygen-containing functional groups have long been overlooked. Accordingly, we studied the coordination behaviour in Pd(ii) complexes of three phosphinoferrocene ligands bearing secondary O-donor groups, Ph2PfcR, wherein R = CHO (1), Ac (2) and CMe2(OH) (3), and fc = ferrocene-1,1′-diyl. Depending on the stoichiometry, reactions of 1-3 (L) with [PdCl2(cod)] (cod = η2:η2-cycloocta-1,5-diene) produced the respective mono- and dipalladium complexes, trans-[PdCl2(L-κP)2] and trans-[PdCl(μ-Cl)(L-κP)]2. Compound [PdCl(μ-Cl)(3-κP)]2 was found to dehydrate readily, giving rise to [PdCl(μ-Cl)(Ph2PfcC(Me)═CH2-κP)]2. Furthermore, ligands 1-3 cleaved [(LNC)Pd(μ-Cl)]2 (LNC = 2-((dimethylamino-κN)methyl)phenyl-κC1), yielding [(LNC)PdCl(L-κP)], which were converted into the cationic complexes [(LNC)PdCl(L)]X (L/X = 1/PF6, 2/SbF6, 3/PF6). Compounds with ligands 1 and 2 were structurally authenticated as stable bis-chelate complexes. In contrast, the product featuring ligand 3 was rather unstable and converted into [(LNC)Pd(AcOEt-κO)(3-κP)][PF6] upon recrystallisation. Weak oxygen coordination was confirmed via reactions of [(LNC)PdCl(L)]X with (PhCH2NEt3)Cl in which the parent chloride complexes were regenerated, and this was further corroborated by DFT computations. Our findings, pointing to hemilabile coordination of 1-3, are relevant for catalysis because de-coordination of the weaker binding O-donor moiety may open a vacant site for a substrate, thereby enhancing the catalytic properties of metal complexes with ligands of this type.

A radical C-H arylation reaction of oxazoles with (hetero)aryl iodides using Cs2CO3 as base/electron donor and 1,1′-bis(diphenylphosphino) ferrocene (dppf) as a catalytic SET mediator is reported. The overall reaction likely follows the general base-promoted homolytic aromatic substitution mechanism through a radical-chain pathway. DFT calculations suggest that dppf forms a complex with CsCO3-, enhancing its SET reducing ability to generate an aryl radical from ArI.

The invention discloses a synthesis method of Josiphos chiral ferrocenyl phosphine ligands, and belongs to the field of organic synthesis. The method is realized through the following steps of using ferrocene as a starting raw material; using aluminum chloride as a catalyst; taking a reaction with phosphonic chloride compound R2PCl; then, taking a reaction with vinyl diaryl phosphine under the catalysis effect of ferric trichloride and D-proline to obtain the Josiphos chiral ferrocenyl phosphine ligands. Compared with the prior art, the synthesis method has the advantages that the steps are few; the operation is simple; the production cost is reduced; the synthesis method is suitable for industrial production. The prepared Josiphos chiral ferrocenyl phosphine ligands can be used as ligands of metal catalysts for catalyzing an unsymmetrical organic reaction; the synthesis method is applied to the fields of medicine synthesis and the like.

The synthesis and characterization of a series of carbosilane-supported ferrocenyl phosphine ruthenium complexes of type SiMe4-n(Fe(η5-C5H4SiMe2(CH2)3)((η5-C5/su

The metallocenyldiphenylphosphines [M(C5H5)(C 5H4PPh2)] with M = Fe(II) (ferrocenyl = Fc), 1, Ru(II) (ruthenocenyl = Rc), 2, Os(II) (osmocenyl = Oc), 3, and Co(III) +PF6- (cobaltocenium hexafluorophosphate = [Cc][PF6]), 4, were synthesized and the crystal structure of RcPPh2, 2, (Z = 4, monoclinic, space group P21/c) was determined. The differences in reactivity of each metallocenyl derivative were such that 1 could be obtained from a Friedel Crafts reaction between ferrocene and PPh2Cl in the presence of AlCl3 as catalyst. Both the ruthenocene and osmocene derivatives 2 and 3 were obtained by reacting the monolithiated metallocene precursor with PPh2Cl. However, monolithiation of ruthenocene had to be achieved via a stoichiometric amount of tBuLi. For osmocene, monolithiation was achieved by a 20% excess of nBuLi. This was evidenced by the failure to isolate any bisphosphine, Oc(PPh2)2, during workup. Complex 4 could not be obtained via phosphination of free cobaltocenium hexafluorophosphate. Phosphine derivatisation of free cyclopentadiene prior to complexation with Co III was required to form [CcPPh2][PF6], 4. The electrochemistry of all phosphines was studied by voltammetric techniques in CH2Cl2/0.1 mol dm-3 [N(nBu) 4][B(C6F5)4]. A reversible one-electron transfer process for the ferrocenyl group of 1 was observed at 0.078 V vs. FcH/FcH+. The osmocenyl and ruthenocenyl derivatives exhibited irreversible metallocenyl oxidations at 0.355 and 0.476 V respectively. The cobaltocenium complex, 4, exhibited two reversible one-electron transfer reductions to liberate first a neutral CoII cobaltocene species at -1.062 V and then an anionic CoI cobaltocene species at -2.122 V. A single electrochemical irreversible, one-electron oxidation at the phosphorus centre which forms a quickly-decomposing phosphorus radical cation, Mc+Ph2P+, was also observed at Epa > 0.754 V. The newly-formed Mc+Ph2P + species or its chemical decomposition products can be oxidized at Epa > 1.090 V vs. FcH/FcH+.

For the first time the anionic phospho-Fries rearrangement has been successfully applied in ferrocene chemistry, giving access to 1,2-P,O-substituted ferrocenes. The 1,3 (O → C)-migration occurs at ferrocenyl phosphates, thiophosphates, phosphite-borane adducts, and phosphinates by treatment with a base such as lithium diisopropylamide at low temperature, whereas the highest yields were obtained starting from diethylferrocenyl phosphate. Complete reduction of the phosphonate to a primary phosphine and subsequent Stelzer P,C cross coupling allowed the synthesis of Fe(η5-C5H3-2-OMe-PPh2) (η5-C5H5) (1). The qualification of 1 as a supporting ligand in palladium-catalyzed Suzuki-Miyaura C,C couplings has been proven by the synthesis of sterically congested tri-ortho-substituted biaryls under mild reaction conditions in good to excellent yields.

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

The synthesis and characterization of a series of metallocenylphosphanes of the type PR2Mc/Se=PR2Mc [Mc = Fc = Fe(η5- C5H4)(η5-C5H5), R = C6H5 (3

A ferrocene-based phosphinopyridine, Ph2PfcPy (1; fc = ferrocene-1,1'-diyl, Py = 2-pyridyl), was newly synthesized by Negishi coupling of Ph2PfcZnCl with PyBr. Its homologous compound Ph2PfcCH 2Py (2) was obtained by reductive dehydroxylation of Ph 2PfcCH(OH)Py (4), the latter resulting via reaction of in situ generated Ph2PfcLi with PyCHO. Depending on the stoichiometry, compounds 1 and 2 react with [PdCl2(cod)] (cod = η2:η2- cycloocta-1,5-diene) to give P,N-chelate and bis-phosphine complexes, [PdCl 2(L-?2P,N)] (5, L = 1;6, L = 2) and [PdCl 2(L-?P)2] (7, L = 1;8, L = 2), respectively. Analogously, [(LNC)PdCl]2 or [(LNC)Pd(MeCN) 2]ClO4 (LNC = [(2-dimethylamino-?N)methyl] phenyl-?C1) react with 1 and 2 to afford complexes featuring these compounds as P-monodentate ligands ([(LNC)PdCl(L-?P)]: 9, L = 1;10, L = 2) or P,N-chelating donors ([(LNC)Pd(L-?2P,N)]ClO 4: 11, L = 1;12, L = 2), respectively. With the exception of compound 9, which undergoes self-ionization in solution, all complexes are defined air-stable solids and were characterized by elemental analysis and conventional spectroscopic methods (multinuclear NMR, IR, and MS). The crystal structures of 4, 5, 7 3 CH2Cl2, 8, 11, and 12 were determined by X-ray crystallography, revealing structural differences resulting from a more flexible geometry of the methylene-spaced ligand 2. The catalytic potential of the Pd complexes 5 and 6 and their in situ generated counterparts (Pd(OAc) 2/L, L = 1, 2) was studied in Suzuki-Miyaura cross-coupling of 4-bromotoluene (13) with phenylboronic acid and in cyanation of the same substrate with K4[Fe-(CN)6]. The results were compared with those obtained under identical conditions with analogous catalysts based on the related donor-symmetric ligand 1,1'-bis(diphenylphosphino)ferrocene.

A new organometallic phosphanylalkene, 1-(diphenylphosphanyl)-1′-(dimethylvinylsilyl)ferrocene (2) was prepared and-together with 1-(diphenylphosphanyl)-1′-vinylferrocene (1)-studied as a ligand in iron- and tungsten-carbonyl complexes. The following complexes featuring the mentioned phosphanylalkenes as P-monodentate donors were isolated and characterised by spectral methods: [Fe(CO)4(L-κP)] (4, L = 1; 5, L = 2) and trans-[W(CO)4(L-κP)2] (6, L = 1; 7, L = 2). In addition, the solid-state structures of 4 and 6 have been determined by single-crystal X-ray diffraction and the electrochemical properties of compounds 1, 2, 4 and 6 were studied by cyclic voltammetry at platinum electrode.

Routes to the title compound were explored based on the cleavage of -ferrocenophanes with aryllithium.Thus the cleavage of (ν5-C5H4)Fe(ν5-C5H3(CHMeNMe2)PPh) with phenyllithium affords (ν5-C5H4Li)Fe(ν5-C5H3(CHMeNMe2)PPh2) and (ν5-C5H4PPh2)Fe(ν5-C5H3Li(CHMeNMe2)) in the ratio 15:85.Hydrolysis of this mixture affords the title compound 4.The lithio-ferrocenes can be treated with XER2 to yield other mixed ligands (E = As, P).A route to 4 via (ν5-C5H4PPh2)Fe(ν5-C5H4C(O)Me) was also established but it is complicated by low yields and many side products such as 5-C5H4PPh2)Fe(ν5-C5H4)>2C=CH2.