A new synthetic route towards methylene-spaced hybrid phosphinoferrocene ligands was developed, making use of a phosphinoferrocene betaine 3-(N,N,N-{[1'-(diphenylphosphino)- ferrocenyl]methyl}dimethylammonium)propane-1-sulfonate (2), that is readily accessible from 1-(diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene (XIX) via treatment with 1,3-propanesultone. The betaine 2 was reacted with sodium alkylsulfinates (alkyl = methyl, phenyl, 4-tolyl) to afford the corresponding sulfones 4. The coordination chemistry of [1'-(diphenylphosphino)ferrocenyl]methyl(methyl)sulfone (4a) was investigated in its zinc(II) complexes. Surprisingly, only insoluble mixed-metal coordination polymers of the general formula [MZnX3(4a)(MeOH)]n (M/X = Na/Br, K/Br, Na/I) and six-centre complex [Li2Zn2Br6(4a)2(MeOH)4(H2O)] could be obtained. Two isomeric homologues of 1'-(diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf, II), viz. 1'-(diphenylphosphino)ferrocenylacetic acid (HIIa) and 1'- [(diphenylphosphino)methyl]ferrocene-1-carboxylic acid (HIIb), were prepared and their coordination preferences were assessed in their palladium(II) complexes. The palladium(II) complexes were prepared by reacting various (acetylacetonate)palladium(II) precursors with these acids with concomitant release of acetylacetone....

The "Ferrocene phosphinoguanidine donors" project presented in this Thesis targeted on the synthesis, coordination chemistry and catalytic applications of a rather uncommon class of compounds combining phosphine and guanidine functional groups in their molecules. Two series of such compounds based on ferrocene backbone (henceforth fc = ferrocen-1,1΄-diyl) were studied. Firstly, a reliable synthetic route towards polar phosphinoguanidinium chlorides [R2PfcCH2NHC(NH2)2]Cl, where R = iso-propyl, cyclohexyl, phenyl and 2-furyl, was developed and these ligands were tested as supporting ligands in palladium-catalysed Suzuki-Miyaura-type reactions in biphasic aqueous mixtures and in rhodium-catalysed hydroformylation of 1-hexene. Deduced from the results, the hydrophilic guanidinium tag had a beneficial effect on the catalytic activity and, particularly, the electron-rich phosphines from this series could serve as a useful alternative to commonly used ligands for catalytic applications in polar or aqueous reaction media. Phosphinonitriles R2PfcCN obtained as intermediates during the synthesis of the abovementioned ligands were additionally used for the preparation of the dimeric complexes [Au2(µ-R2PfcCN)2][SbF6]2, in which the gold(I) centre was stabilised by nitrile coordination. These complexes proved...

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6 Abstract The first part of this Thesis describes the preparation of a novel phosphanyl-ferrocene amine, Ph2PfcCH2NH2 (1; fc = 1,1'-ferrocendiyl) in two steps from the known aldehyde Ph2PfcCHO. An oxime Ph2PfcCH=NHOH was prepared firstly by a condensation reaction, and subsequently treated with Li[AlH4] to give the desired amine. The amine was converted into its more stable hydrochloride salt, Ph2PfcCH2NH3Cl. Derivatization of amine 1 was examined through the preparation of a series of phosphanyl-urea ligands Ph2PfcCH2NHC(E)NR1 R2 . Some of these compounds were also prepared via an alternative method employing reductive amination reaction. These donors and their Pd(II) complexes were evaluated in Pd-catalyzed reaction of arylbromides with K4[Fe(CN)6] in order to prepare corresponding benzonitrile derivatives using aqueous reaction solvents. The reaction proceeds with excellent yields and purity when 1 mol.% of Pd- catalyst is used (at 100 řC for 3 hours), especially for electron-rich bromobenzenes. Substrates with electron-withdrawing substituents react significantly slower and corresponding hydrolytic products (benzamides) are isolated. The coordination properties of phosphanyl-amine 1 were examined towards Cu(I) ions. Thus, reaction of 1 with [Cu(MeCN)4][BF4] provided bis-chelate complex [Cu(1- κ2...

Ferrocene is an important molecule in the field of chemical biology due to its stability, unique redox property and significant lipophilicity for better cellular delivery. The medicinal importance of ferrocene is well recognized after its successful incorporation into breast cancer drug tamoxifen and antimalarial drug chloroquin. Designing ferrocene conjugated transition metal complexes is an interesting area of research in the field of photodynamic therapy, a new modality of light activated cancer treatment. The objective of the present thesis work is to develop photoactive ferrocene conjugates showing DNA photocleavage and photocytotoxic activity. We have synthesized the ferrocene conjugated imidazophenanthroline derivative which exhibits visible light induced DNA photocleavage activity and photocytotoxicity in HeLa cell line. The corresponding phenyl analogue is found to be inactive. Polypyridyl platinum(II) complexes of ferrocenyl as well as phenyl moiety are prepared and studied their interactions with calf thymus DNA. The cytotoxicity of the complexes enhance significantly upon irradiation of UV-A light of 365 nm. To enhance the photodynamic potential and to understand the role of organometallic ferrocenyl moiety, ferrocene conjugated terpyridyl copper(II) complexes having planar phenanthroline bases are prepared. The interaction of these complexes with duplex DNA and their photo-induced DNA cleavage and anticancer activity in HeLa cancer cells are studied. The complexes are able to generate ROS in the presence of visible light which causes DNA damage as well as cell death. The importance of ferrocenyl moiety is evidenced from the less activity of the corresponding phenyl analogues complex. We have prepared copper(II) complexes of ferrocenyl methyl dipicolylamine ligand to understand the role of terpyridyl moiety. These complexes lacking any conjugation between the copper(II) and the ferrocenyl moiety are found to be less active compared to the terpyridyl conjugated system. The copper(II) complexes are found to show undesirable dark cytotoxicity in the presence of cellular thiols like GSH. To overcome the dark toxicity problem and to understand the mechanistic aspects of DNA photocleavage and photocytotoxicity, a series of binary ferrocene conjugated terpyridyl complexes of Fe(II), Co(II), Cu(II) and Zn(II) are prepared and their DNA photocleavage and anticancer activity studied. The zinc(II) complex having redox-active ferrocenyl moiety and redox-inactive zinc(II) center exhibits significant PDT effect with low dark toxicity compared to its copper(II) analogue. The ferrocenyl moiety plays an important role towards showing photocytotoxic activity since its phenyl analogue is inactive in nature. Finally, the present thesis work opens up a new strategy for designing and developing new ferrocene based metal complexes as novel photosensitizers for PDT applications.

The synthesis, characterisation and anion binding properties of a series of mono- and bifunctional Lewis acidic borylferrocene compounds are described within this thesis. The original parent compound FcBMes₂ (3.1), revealed a versatile route for the synthesis of such borylferrocenes and subsequently the analogous compound Fc*BMes₂ (3.2) was synthesised. The anion binding properties of (3.1) and (3.2) were investigated and both were shown to bind one equivalent of cyanide. The binding event was signalled by an electrochemical shift (ca. -560 mV) and a quenching of bands at 510 or 542 nm respectively in the UV/Vis spectrum, while the mode of anion binding in the solid state was established by X-ray crystallography for [ⁿBu₄N]⁺[(3.1)·CN]⁻. Incorporation of a suitable redox active dye (i.e. tetrazolium violet for 3.2) allowed conversion of the electrochemical response to a colorimetric change on cyanide binding. However, a competing response for fluoride is also seen for (3.1) and (3.2). Thus a two component system is reported involving (3.2) and the boronic ester FcB(OR)₂ (3.4), [where (OR)₂ = OCH(Ph)CH(Ph)O], which from previous research is known to selectively bind fluoride, and allows for selective colorimetric cyanide sensing by simple Boolean AND/NOT logic. 1,4-C₆H₄(BMes₂)[B(OR)₂] (3.5), 4,4-C₁₂H₈(BMes₂)[B(OR)₂] (3.6) and 1,1′-fc(BMes2)(B(OR)2) (3.7) were synthesised as possible single molecules for discrimination between cyanide and fluoride. (3.5) and (3.6) proved only capable of binding one equivalent of either anion, (3.7) showed some ability to bind two equivalents of fluoride however based on ESI-MS studies although only in the presence of a large excess of anion. Systematic variation of the para-boryl substituent was investigated by synthesis of compounds FcB(Xyl^F)₂ (4.1), FcB(Xyl)₂ (4.2) and FcB(Xyl^OMe)₂ (4.3). Anion binding studies reveal a linear increase in fluoride binding affinity consistent with that expected based on the para,/em>-Hammett parameters, however with only minor differences, while no pattern is observed with respect to their cyanide binding capabilities. The addition of neutral and cationic peripheral substituents has been investigated through synthesis of [1,2-fc(CH₂NMe₂)BMes₂] (4.6) and [1,2-fc(CH₂NMe₃)BMes₂]⁺ (4.7). Subsequent binding studies revealed (4.6) to be moisture sensitive, however reaction of (4.7) with fluoride and cyanide led to formation of the adducts [(4.7)·F]⁻ and [(4.7)·CN]⁻. The anion affinity of (4.7) exhibits a substantial increase when compared to the parent compound (3.1). Even when compared to the isomeric 1,1′ system an increase of approximately three orders of magnitude is seen attributed to the closer nature of the cationic charge and in the fluoride adduct the presence of a cooperative intramolecular hydrogen bond. The 1,1′-bifunctional analogues of the mono-substituted systems were synthesised [e.g. 1,2-fc(BMes₂)₂ (5.1)] and shown to complex two equivalents of fluoride or cyanide in acetonitrile. The 1:1 cyanide adduct of (5.1) was isolated in chloroform however, no evidence for chelation was observed. The analogous systems 1,2-fc(BMes₂)₂ (5.5), 1,2-fc(BXyl₂)2 (5.7), and 1,2-fc(BMes₂)(BXyl₂) (5.8) were also investigated. Reaction of (5.5) with fluoride and cyanide revealed it to bind only one equivalent of either anion, neither however was bound in a chelating fashion although X-ray crystallography revealed cyanide binds exo whilst fluoride binds endo to the B···B cavity. Finally the kinetics of fluoride binding were studied by UV/Vis spectroscopy and showed a systematic increase in rate constant upon reduction of steric bulk.

Development of synthetic routes toward two general organometallic frameworks was undertaken. The first project involved synthetic attempts of substituted and unsubstituted ferroceno[c]thiophene while the second one was the synthesis of 1,2-dithienylmetallocenes. The long-term goal of this work is to lay the foundations for study of electronic, electrochromic, redox, and optical properties of thiophene-based materials integrated with organometallic systems such as ferrocene, ruthenocene and cymantrene. The synthetic pathway for the target molecule in the first project involved converting 1,2-bis(hydroxymethyl)ferrocene to 1,2-bis(thiouroniummethyl)ferrocene with thiourea under acidic conditions. Refluxing the salt in base followed by acidification resulted in 1,2-bis(mercaptomethyl)ferrocene, which is oxidized to the cyclic ferroceno[d]-1,2-dithiane. Ring contraction of cyclic dithiane gave the thioether, ferroceno[c]-2,5-dihydrothiophene. Periodate oxidation of the thioether gave ferroceno[c]-2,5-dihydrothiophene-S-oxide (1), a potential precursor for ferroceno[c]thiophene via Pummerer dehydration. Attempts to dehydrate 1 and to trap the resulting thiophene in situ indicated instability of the target compound. Synthesis of ferroceno[c]thiophene with electron-donating as well as electron-withdrawing substituents at the 2,5-positions of the thiophene ring was attempted. 1,2–Dithienylethenes and their derivatives have gained increased attention due to their exceptional photochromic property. They tend to be thermally irreversible but photochemically reversible, which is a vital for their potential use in optical memories, switches and other optoelectronic applications. Inspiration of the second project was that incorporation of 1,2-dithienyl systems into metallocenes would enhance the general properties of the molecule, including stability, fatigue resistance, solid-state reactivity and higher sensitivity. 1,2-Dithienylferrocene was successfully synthesized. The synthetic pathway for 1,2-dithienylferrocene involved the reaction of α-bromo-3-acetyl-2,5-dimethylthiophene (1) with ethyl 4-(2,5-dimethylthiophen-3-yl)-3-oxobutanoate (2) to give 2,3-diarylcyclopent-2-en-1-one (3). Compounds 1 and 2 were synthesized following literature methods. Compound 3 was then converted to its cyclopentadienide form by first reducing the ketone to alcohol using LAH, followed by dehydration and then deprotonation of the substituted cyclic diene using butyllithium to give 1,2-bis(2,5-dimethylthiophene)-2,4-cyclopentadien-1-yl)lithium (4). [Fe(fluorenyl)(Cp)] was then used as a transfer reagent and reacted with 4 to yield the target compound.

Title: Homologous ferrocene phosphines Author: Bc. Petr Vosáhlo Department: Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D., DSc. Abstract: This thesis describes the synthesis and coordination behaviour of ferrocene diphosphines derived from 1,1'-bis(diphenylphosphino)ferrocene (dppf). Dppf is one of the most succesful ferrocene ligands, which can be used in various metal-catalyzed reactions. This study aimed to prepare analogous ligands with one dialkylphosphino substituent and one (diphenylphosphino)methyl group. These ligands were oxidized by KSeCN to afford the corresponding phosphinoselenides. The phosphinoselenides were used to assess sigma-donor abilities by measuring the coupling constant 1 JSeP via 31 P NMR spectroscopy. Lastly, the coordination behaviour of these ligands in palladium complexes was studied. The homologous ligands usually formed a mixtures containing a chelate complex and dimeric species with trans- coordinated ligands. Key words: ferrocene, phosphines, homologous ligands, palladium(II) complexes, structure elucidation.

"Catalytic growth of Carbon Nanotubes (CNT) provides important advantages of controlling their diameters and possibly chirality. Our work involved growing CNT on model and supported catalyst by catalytic decomposition of carbon source such as benzene, methane and propylene. On supported catalyst, iron nitrate was deposited on alumina and reduced to form metallic iron clusters. These were reacted at 700 - 950 C under varying benzene concentrations. Multi Walled CNT (MWNT) grew below 800 C and Single Wall CNT (SWNT) are observed at 850 C and above as confirmed by TEM and Raman. Model catalysts were studied by producing CNT from ferrocene which acted as the carbon and catalyst source on Silica/Si (100). Large yield of MWNT was observed at 900 C. MWNT grew perpendicular to the model support as seen by SEM. In another model catalyst study, iron salt clusters were deposited on silica/Si (100) by spin coating, controlling their diameters by solution concentration and speed of spinning. Agglomeration of clusters at high temperatures produces only MWNT on silica/Si (100). Cluster agglomeration can be reduced with strong support metal interaction such as with alumina. We deposited alumina on silica/Si (100) by atomic layer deposition, with conformal coatings on surface and low relative roughness. Alumina film was stable under reaction temperatures of 900 C. Cluster deposition on alumina by spin coating was difficult because of different surface acidity compared to silica. Clusters on alumina did not agglomerate at high reaction temperatures. We report effect of parameters such as the temperature of reaction, conditions of pretreatment such as reduction and oxidation of catalyst precursor, type of precursor, type of carbon source, and type of support material on growth of CNT. The role of spin coating in controlling the diameter of salt clusters deposited is discussed. We also report deposition of alumina on top of silica/Si (100) by atomic layer deposition and the effect of deposition and calcination temperatures on the alumina film integrity."

Observando o atual interesse em polímeros organometálicos para diversas aplicações, foi feita a síntese de uma série de polímeros conjugados contendo ferroceno na cadeia principal visando à investigação de suas propriedades, em especial fenômenos magnetorresistivos, magneto-ópticos e de óxido-redução. Os polímeros preparados pelo método de McMurry foram os seguintes: PFV: poli(1,1\'-ferrocenilenovinileno) e PFV-DOPPV-M: poli[1,1\'-ferrocenilenovinileno-alt-(2,5-di-n-octilóxi)-1,4-fenilenovinileno]. Outros dois polímeros foram preparados utilizando o método de polimerização de Wittig, o PFV-DOPPV-W: poli[1,1\'-ferrocenilenovinileno-alt-(2,5-di-n-octilóxi)-1,4-fenilenovinileno] e o PFV-DMPPV: poli[1,1\'-ferrocenileno-vinileno-alt-(2,5-dimetóxi)-1,4-fenilenovinileno]. A síntese de polímeros contendo segmentos π-conjugados equenos e bem definidos separados por segmentos não-conjugados é uma das melhores stratégias para a obtenção de polímeros emissores de luz azul. Com base nesse argumento foi feita a síntese de uma série de polímeros contendo um derivado metoxilado de bisfenol-A (BPA) na cadeia principal, alternando-se com unidades de PPV ou PFV que apresentam segmentos conjugados bem definidos. Os polímeros preparados foram os seguintes: BPA-DOPPV:poli[2,2-bis(4-metoxifenil)-propano-alt-2,5-(di-n-octilóxi)-1,4-divinilbenzeno]; BPA-PPV: poli[2,2-bis(4-metoxifenil)-propano-alt-1,4-ivinilbenzeno]; BPA-DMPPV: poli[2,2-bis(4-metoxifenil)-propano-alt-2,5-dimetóxi-1,4-ivinilbenzeno]; BPA-DBPPV: poli[2,2-bis(4-metoxifenil)-propano-alt-2,5-dibromo-1,4-divinilbenzeno] e BPA-PFV: poli[2,2-bis(4-metoxifenil)-propano-alt-1,1\'-divinil-ferroceno]. Todos os polímeros obtidos foram caracterizados por métodos espectroscópicos (UV-VIS, IR, RMN), análises térmicas, SEC, entre outras. Algumas aplicações foram estudadas para esses polímeros, tais como a construção de um eletrodo de ORP modificado, a produção de diodos orgânicos emissores de luz (OLEDs) e a determinação da resposta \"olfativa\" de sensores de gases. / Owing to the current interest in organometallic polymers and their applications, a group of conducting polymers containing ferrocene in the main chain was synthesized aiming the study of their magnetoresistive, magneto-optic and redox properties. The following polymers were prepared via McMurry method: poly(1,1\'-ferrocenylenevinylene) (PFV) and poly[1,1\'-ferrocenylenevinylene-alt-(2,5-di-n-octiloxy)-1,4-phenylenevinylene] (PFV-DOPPV-M). Two other polymers were synthesized via Wittig method: poly[1,1\'-ferrocenylenevinylene-alt-(2,5-di-n-octiloxy)-1,4-phenylenevinylene] (PFV-DOPPV-W) and poly[1,1\'-ferrocenylene-vinylene-alt-(2,5-dimethoxy)-1,4-phenylenevinylene] (PFV-DMPPV). The synthesis of polymers with well-defined small π-conjugated segments separated by non-conjugated segments is one of the best strategies to obtain blue light emitting polymers. Based on this statement the synthesis of several polymers formed by methoxylated bisphenol-A (BPA) alternated with PPV or PFV units was performed. The prepared polymers were the following: poly[2,2-bis(4-methoxyphenyl)-propane-alt-2,5-(di-n-octiloxy)-1,4-divinylbenzene] (BPA-DOPPV), poly [2,2-bis(4-methoxyphenyl)-propane-alt-1,4-divinylbenzene] (BPA-PPV), poly[2,2-bis(4-methoxyphenyl)-propane-alt-2,5-dimethoxy-1,4-divinylbenzene] (BPA-DMPPV), poly[2,2-bis(4-methoxyphenyl)-propane-alt-2,5-dibromo-1,4-divinylbenzene] (BPA-DBPPV) and poly[2,2-bis(4-methoxyphenyl)-propane-alt-1,1\'-divinylferrocene] (BPA-PFV). All the synthesized polymers were characterized by spectroscopic methods (UV/VIS, IR, NMR), thermal analysis, SEC, among others. Some applications to these polymers were studied: a modified ORP electrode, organic light emitting devices (OLEDs) and gas sensors.