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A straightforward synthetic route to a selection of new ferrocenyl complexes bearing different organopalladium fragments is reported. The target complexes were fully characterized by Nuclear Magnetic Resonance, High Resolution Mass Spectrometry, Infrared Spectroscopy, X‐ray Diffraction, and electrochemical techniques. All compounds, with the exception of Pd(0)‐olefin derivatives, showed excellent antitumor activity on ovarian cancer cells and, in the case of Pd (II)‐allyl and Pd (II)‐butadienyl complexes, a lower cytotoxicity towards normal cells. [ABSTRACT FROM AUTHOR]

Ferrocenyl methyl ketone reacts with aromatic aldehydes yielding 1-ferrocenyl-3-aryl-propenones (chalcones), which upon treatment with Lawesson’s reagent (LR) are converted to the corresponding thiochalcones. The latter enter the thia-Diels-Alder reaction with acetylenic dienophiles (DMAD and methyl propiolate) to give ferrocenyl-substituted 4H-thiopyrans. In the case of methyl propiolate, the formation of the six-membered ring occurs with complete regioselectivity. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterization of two new meso‐ferrocenylporphyrins, with the ferrocenyl unit attached at the para position of a C6F4 group by a CN bond with NH(CH2)2NH (2a) and NH(CH2)4NH (2b) spacers. Compounds 2a and 2b were characterized through elemental analyses, electrospray ionization high‐resolution mass spectrometry, 1H NMR, UV–visible and fluorescence spectroscopies, electrochemistry and spectroelectrochemistry. The free base porphyrin 2 was included for comparison purposes. The binding ability of 2 and the porphyrin derivatives 2a and 2b with calf thymus DNA was determined using UV–visible and fluorescence spectroscopies. The results suggest that the interaction of these systems most probably occurs through π‐stacking by non‐classical modes involving the partial insertion of the C6F5 ring between adjacent base pairs on DNA and possible hydrogen interaction with the aliphatic NH(CH2)nNH (n = 2 or 4) groups with calf thymus DNA. Moreover, we also demonstrate that porphyrins generate singlet oxygen species and show good photostability after irradiation. [ABSTRACT FROM AUTHOR]

This article describes the synthesis, characterization and DNA-binding assays of a series of oxadiazoles derived from ( E )-3-ferrocenylacrylic acid. The compounds were obtained in satisfactory yields and characterized by NMR and high resolution mass spectrometry analysis. Additionally, the X-Ray characterization of compound 8a was investigated. A series of ferrocenylethenyl-substituted 1,3,4-oxadiazolyl-1,2,4-oxadiazoles was prepared and studied by UV-visible and electrochemical techniques. The characteristic signals of the redox-active ferrocene/ferrocenium couple were monitored, which allowed verification of the influence of electron-withdrawing oxadiazole heterocycles and their dependence on the 1,2,4-oxadiazole substituent. Also, DNA-binding experiments were performed by UV-vis and emission titrations with ct-DNA. [ABSTRACT FROM AUTHOR]

Methods for the synthesis of hetaryl and ferrocenyl thioketones as well as applications of this class of organic sulfur compounds in the synthesis of both sulfur-containing and sulfur-free organic products are summarized. The most important applications relate to [2+2]-, [3+2]-, and [4+2]-cycloadditions. Aromatic thioketones react with diazomethane at −70°C, and the formed 1,3,4-thiadiazolines can be used as convenient precursors of reactive thiocarbonyl S-methanides. In contrast, the hetaryl thioketones do not form this type of cycloadducts. Reactions of hetaryl thioketones with thiocarbonyl S-methanides are proposed to occur via a stepwise diradical mechanism. Aryl and hetaryl thioketones react as prone heterodienophiles with cyclic and acyclic dienes. The first asymmetric synthesis of dihydrothiopyranes from aryl and hetaryl thioketones was performed using al-proline-derived organocatalyst. Hetaryl thiochalcones are useful heterodienes for the preparation of hetaryl-substituted dihydrothiopyrans. [ABSTRACT FROM PUBLISHER]

Ferrocenyl derivatives and half-sandwich iridium(III) complexes have received extensive attention in the field of anticancer. In this paper, series of configuration-controlled ferrocene-modified half-sandwich iridium(III) pyridine complexes were prepared. The combination of half-sandwich iridium(III) complexes and ferrocenyl unit successfully improved the anticancer activity of these complexes, especially for trans -configurational one towards A549 cells, and the best-performing (Fe Ir5) was almost 3.5 times more potent than that of cisplatin. In addition, these complexes could inhibit the migration of A549 cells. Complexes can accumulate in intracellular lysosomes (PCC: >0.75), induce lysosomal damage, disturb the cell circle, decrease the mitochondrial membrane potential, improve the intracellular reactive oxygen species (ROS) levels, and eventually lead to apoptosis. Meanwhile, complexes could bind to serum protein following a static quenching mechanism and transport through it. Then, ferrocene-modified half-sandwich iridium(III) pyridine complexes hold the promise as potential organometallic anticancer agents for further investigation. Ferrocene-appended iridium(III) pyridine complexes could induce lysosomal damage, increase intracellular ROS level, then lead to A549 cell apoptosis. [Display omitted] • Ferrocene-appended iridium(III) pyridine complexes were prepared. • Combination of ferrocene and iridium(III) complexes improved anticancer activity. • Complexes could inhibit cancer cell migration. [ABSTRACT FROM AUTHOR]

A direct, silver-mediated C−H phosphonylation reaction of ferrocenyl anilides and dialkyl phosphites was developed. This methodology can tolerate a variety of functional groups and is free of palladium and copper. Moreover, mechanistic studies have revealed that the reaction pathway is of a radical type. [ABSTRACT FROM AUTHOR]

Host–guest interactions between ferrocene (Fc) and its derivatives containing electron donating and electron withdrawing substituents viz., 2-ferrocenyl benzoxazole (FcOz) or 2-ferrocenyl benzothiazole (FcTz) and cucurbit [7]uril (CB[7]) host have been analyzed employing density functional theory incorporating various exchange correlation functionals. Electronic structures of these complexes reveal the encapsulation of ferrocene ring within the CB[7] container with the benzoxazole or benzothiazole substituent interacting with host portals via C = O ⋯ H interactions. Further the M06-2X based calculations show stronger host–guest binding compared to those predicted from wB97x, PBE0 and B3LYP functionals. The contributions of electrostatic and other dispersive interactions toward such binding have been assessed. The 1 H NMR chemical shifts from the gauge independent atomic orbital (GIAO) theory using different functionals demonstrated that subtle changes in δ H signals of cyclopentadienyl protons and those encapsulated in the CB[7] cavity in water are better reproduced by the wB97x functional. Calculated infrared spectra revealed that the complexation is accompanied by frequency shift of the C–N stretching in benzoxazole or benzothiazole ring, and the characteristic methine and carbonyl vibrations of CB[7]. The direction of such frequency shifts has been explained from the natural bond orbital analyses and ‘Quantum Theory of Atoms in Molecules’ approach. Time dependent density functional theory calculations further demonstrated that substitution on the cyclopentadienyl ring brings a bathochromic shift of the ~ 200 nm band in the electronic spectra for the unsubstituted Fc-CB[7] complex. Furthermore, FcOz@CB[7] or FcTz@CB[7] complexes exhibit low energy absorption band at ~ 480 nm in its electronic spectra as a result of intramolecular charge transfer from 3d orbitals of Fe to π* orbitals of benzothiazole or benzoxazole, unlike that in the Fc@CB[7] complex. [ABSTRACT FROM AUTHOR]

A series of structurally novel organometallic compounds ( 3a – g ) based on 1-biaryl-3-ferrocenylprop-2-en-1-one, were synthesized by the Suzuki-Miyaura cross-coupling reaction for applications as nonlinear optical (NLO) and liquid crystal (LC) materials. Notably, a single crystal of this class of compounds was obtained for the very first time, and it was found that the two phenyl rings of the chalconyl group were nearly coplanar to one of the cyclopentadienyl rings of ferrocene. Due to the high degree of conjugation, all the chalcone analogues of ferrocenyl biaryl derivatives displayed strong second harmonic generation (SHG) response (0.45–0.60 × 10 −30 esu, 3–4 times greater that of potassium dideuterophosphate (KDP)). The density functional theory (DFT) was employed to calculate the main molecular orbital energies and compositions of 3d , based on its crystallographic structure. Compound 3d was found to exhibit excellent NLO properties due to its low E gap and superior charge transfer ability within the conjugated system. This work presents a new approach for the preparation of this class of ferrocenyl biaryl derivatives, which may have potential applications as NLO materials. [ABSTRACT FROM AUTHOR]

New complexes with six ferrocenyl (Fc) groups connected to ZnII or CdII tris(2,2′-bipyridyl) cores are described. A thorough characterisation of their BPh4− salts includes two single-crystal X-ray structures, highly unusual for such species with multiple, extended substituents. Intense, visible d(FeII)→π* metal-to-ligand charge-transfer (MLCT) bands accompany the π→π* intraligand charge-transfer absorptions in the near UV region. Each complex shows a single, fully reversible FeIII/II wave when probed electrochemically. Molecular quadratic nonlinear optical (NLO) responses are determined by using hyper-Rayleigh scattering and Stark spectroscopy. The latter gives static first hyperpolarisabilities β0 reaching as high as approximately 10−27 esu and generally increasing with π-conjugation extension. Z-scan cubic NLO measurements reveal high two-photon absorption cross-sections σ2 of up to 5400 GM in one case. DFT calculations reproduce the π-conjugation dependence of β0, and TD-DFT predicts three transitions close in energy contributing to the MLCT bands. The lowest energy transition has octupolar character, whereas the other two are degenerate and dipolar in nature. [ABSTRACT FROM AUTHOR]

The effects of heteroatom-containing ferrocene catalysts on the materials produced from chemical vapour deposition (CVD) floating catalyst synthesis were investigated. Specifically, the influence of nitrogen- and oxygen-containing ferrocenoyl imidazolide and ( N-phenylcarbamoyl)ferrocene, and sulfur- and oxygen-containing S, S-bis(ferrocenylmethyl)dithiocarbonate on the structural morphology and distribution of the products as well as properties such as the thermal stability and crystallinity were studied. In addition, the influence of reaction parameters such as catalyst concentration and temperature were also investigated. The nitrogen-containing catalysts produced N-doped multi-walled carbon nanotubes (N-MWCNTs), whereas the sulfur-containing catalyst produced primarily nano- and microspheres. A concentration of 2.5 wt% ferrocenoyl imidazolide was shown to be optimal for the synthesis of MWCNTs at 850 °C, with very low metal iron residue, highest thermal stability and highest yield (95%). In general, bamboo compartment length for N-doped MWCNTs increased with temperature. Crystallinity trends were shown to be independent of catalyst and catalyst concentration in all cases and only dependent on temperature. The average diameter for MWCNTs was shown to be dependent on temperature, choice of catalyst and catalyst concentration in all cases. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: A new inorganic–organic hybrid compound [FTMA]2[Co(NCS)4] (FTMA=ferrocenylmethyltrimethylammonium cation) has been synthesized and characterized by IR, UV, elemental analysis and X-ray crystallography. Co(II) atom has a distorted tetrahedral environment with four N atoms of four NCS− anions. In the solid state there are C–H⋯π interactions between adjacent ferrocenyl cations, which generate one-dimensional (1-D) supramolecular chain, and C–H⋯S hydrogen bonds between [FTMA]+ cations and cobalt thiocyanate anions. The title compound shows strong purple fluorescence emission in the solid state at room temperature. [Copyright &y& Elsevier]

Abstract: Novel slender hydrophobic ferrocenyl molecules (1–9) synthesized by efficient one-pot method in global high yields having poor aqueous solubility are driving molecules in formation of inclusion complexes with β-CD to self-assemble into vesicles in water. These vesicles were observed by TEM and confirmed by DLS, SEM and AFM for the first time. According to the complex stoichiometry and stability constant by UV, the one-head and one-tail “tadpole-like supramolecular amphiphiles” based on these inclusion complexes between driving molecules and β-CD were firstly assumed to construct these vesicles. Effects of chain length in driving molecules on formation of vesicles were estimated for the first time. The response of these vesicles to an oxidizing agent was also discussed. This work promotes to establish complete theoretical system of “supramolecular amphiphiles” and paves the way to combine supramolecular host–guest chemistry and membrane chemistry for potentially functional applications such as biomaterials for the separation of bacteria. [Copyright &y& Elsevier]

New ferrocenyl derivatives (a β-ketoester and a β-diester) were synthesised and linked to fullerene C60, with the aim to elucidate factors involved in intramolecular electronic communication. These are the first examples of fullerene functionalised with ferrocenes via the cyclopropanation reaction. The resulting dyads were characterised. [Copyright &y& Elsevier]

The ground and excited states dipole moments and the second order hyperpolarizabilities of a series of oxazolinyl-ferrocenyl derivatives have been measured. After complexation of the oxazoline group with a second metal ion, the new bimetallic complexes show an increased hyperpolarizability, as determined by the EFISHG technique. A copolymer of the same bimetallic complex with methyl methacrylate has been synthesized, and the second order susceptibility has been measured by second harmonic generation at 1.06µm. [ABSTRACT FROM AUTHOR]

Six glucoside compounds have been synthesized by means of phase-transfer catalytic method and deacetylation from the starting material ferrocene. Their structures have been confirmed by elementary analysis, IR,1HNMR and MS. The antianemic activities of some compounds have also been tested. Results indicate that these glucoside compounds possess the antianemic activities and therefore, the further study is well worth making. [ABSTRACT FROM AUTHOR]

Excited-state study of amino-ferrocenyl porphyrin derivatives • Excited state and intersystem crossing mechanism for amino-ferrocenyl porphyrins were investigated. • NLO properties of amino-ferrocenyl substituted porphyrins were investigated. • Z-Scan technique was explored in the amino-ferrocenyl porphyrins derivatives. • Aliphatic chain spacers size not affected the associated electronic transitions and properties. The spectroscopic study and characterization of mono-(amino-ferrocenyl) porphyrins has increased during the last years. These molecules can be synthesized in such a way that their linear and nonlinear optical parameters are modulated, opening the possibility for new applications, such as in photodynamic therapy. In this work, we perform a spectroscopic characterization of a group of five free-base porphyrins, three of them having a C 6 F 4 group attached to an amino-ferrocene moiety through a −NH(CH 2) n NH− spacer, in which n = 2, 4 or 6. These three molecules differ by the size of the aliphatic chain. For this study, we employ linear as well as nonlinear optical spectroscopic techniques, such as the Z-Scan and time resolved fluorescence. Decay times, absorption cross-sections and quantum yields were determined, and the results suggest that, for this group of molecules, the differences in the aliphatic chain sizes joining the ferrocenyl unit to the C 6 F 4 group at the para -position aryl ring do not influence significantly the optical parameters. Further, DFT calculations confirm that the UV–vis absorbance and the associated electronic transitions are not affected by the size of the aliphatic chain spacers. Thus, it is possible to state that these molecules can interact with biomolecules through the ferrocene unit while keeping their optical properties unchanged. [ABSTRACT FROM AUTHOR]