Showing papers on "Ferrocene published in 1972"

The Palladium-catalyzed Ferrocenylation of Olefins

Abstract: Ferrocenylpalladium chloride, prepared in situ from chloromercuriferrocene and lithium chloropalladite, reacts readily with various olefins to produce alkenylferrocene derivatives. Enol esters and allylic alcohols also react to form (2-oxoalkyl)- and (3-oxoalkyl)-ferrocene derivatives. The synthesis of 1,1′-dialkenylferrocene derivatives from 1,1′-bis(chloromercuri)ferrocene, olefins and palladium salt is also reported. The reaction may proceed by means of a catalytic amount of the metal salt and by the aid of cupric chloride; it provides an extremely convenient method for the synthesis of a wide variety of ferrocene derivatives.

My Way in Organometallic Chemistry

Abstract: Publisher Summary This chapter discusses organometallic chemistry. Results obtained from the synthesis of diphenylbromonium tetrafluoroborate, diphenylchloronium tetrafluoroborate, and triphenyloxonium tetrafluoroborate by decomposing benzenediazonium tetrafluoroborate in bromobenzene, chlorobenzene, and diphenyl ether, respectively, are presented in the chapter. The chapter also discusses the early investigations into organometallic exchange reactions and the investigation of the Grignard reaction and the stereochemistry of electrophilic or homolytic substitutions. Ferrocene organomercurials are used to prepare a number of other derivatives such as halogen-, sulfur-, or selenium-containing compounds; biferrocenyl; and triphenylmethylferrocene. Ferrocene differs from benzene in that the latter is equally sensitive to electron-donating and electron-accepting substituents while ferrocene is susceptible to the electron-accepting ones only. Ligand exchange of ferrocene is described in detail in the chapter. The investigations showed that one of the cyclopentadienyl groups of ferrocene could be replaced by an arene ligand, whereby the arene cyclopentadienyl iron cation was formed. The chemical reduction (Na/Hg, sodium naphthalide) revealed that the primary product disproportionated to give ferrocene and an arene. The chapter also describes organotitanium compounds, π -allyl complexes, and π -acetylene complexes of transition metals.

Syntheses and Reactions of Ferrocene-Containing Polymers, VI. Polarography and Electron Transfer Equilibria of Some Ferrocene-Containing Polymers

Abstract: Polarography and electron transfer equilibria of some ferrocene-containing polymers were studied in comparison with small-molecule analogs. The oxidation half-wave potentials of polyvinylferrocene and polydivinylferrocene (almost completely cyclized) in CH2Cl2 were close to those of ferrocene and [3]ferrocenophane, respectively. This is in line with structural similarity. Only one oxidation step was observed in the polarogram of triferrocenylbenzene and polyethynylferrocene, suggesting that the electronic interactions between ferrocene units are small in these compounds. Electron transfer equilibrium was observed between ferrocene units in polymer and iodine. Equilibrium constants of the [3]ferrocenophane unit were greater than those of the unbridged ferrocene unit. The ferrocene unit in polymer showed greater equilibrium constants than those of their small-molecule analogs.

Bis-(π-arene-π-cyclopentadienyliron) dications

Abstract: Treatment of the π-arene-π-cyclopentadienyl cations (1a,b) and (2) with ferrocene in the presence of a Lewis acid affords the novel bis-(π-arene-π-cyclopentadienyliron) dications (3a,b) and (4).

The Synthesis and Stereochemistry of 2,3-Ferrocenocyclopentenone

Abstract: An optical isomer of 2,3-ferrocenocyclopentenone (X) has been synthesized from methyl (1S) (−)-2-hydroxy-methylferrocenecarboxylate via a six-step synthesis. The absolute configuration of (−)-X has been confirmed by a comparison of its CD and ORD curves with those of the corresponding ferrocene homologs previously recorded. The mass spectrum of X is also discussed.

Recent advances in the chemistry of organometallic compounds of the actinide elements

Abstract: A brief history of the preparation of organometallic compounds (the tricyclopentadienyls) of the Sf-electronic series, the actinides. is presented. The special micro-techniques employed for the heavier actinides. available for investigation in only microgramme quantities. are described. The compounds of the heavier actinides are characterized by largely ionic bonding. The more recent preparation of cyclooctatetraenyl compounds of the actinides is also described. The uranium(IV) compound is relatively stable. covalent, with a sandwich it-electron structure involving Sf-electrons since this structure is analogous to ferrocene. the name uranocene has been proposed. These organometallic compounds are relatively volatile and thus sublime at relatively low temperatures. The prospect for preparing organometallic compounds of the heaviest actinides and the transactinides. presently available only on a one-atom-at-atime basis. is also examined on the basis of inorganic chemistry experiments that have already been performed with such small quantities of these and similar elements. Organometallic chemistry has its origin in the discovery of diethyizinc by Frankland in 1849 and even still earlier work on platinum chemistry performed by the Danish chemist Zeise in 1827. The interest of most transition metal chemists, however, dates from the preparation of ferrocene in 1951. Other d-transition metal 'sandwich' compounds and also compounds of an ionic nature between cyclopentadiene and the 41-transition metals, the lanthanides, were then prepared. In order to study possible metal to carbon bonding in the 51-electronic series, the actinides, Reynolds and Wilkinson1 extended organometallic chemistry to element 92 in 1956 by preparing uranium tricyclopentadienyl chloride, U(Cp)3C1 (where Cp C5H5). The reaction of uranium tetrachioride with sodium cyclopentadienide, NaCp, in tetrahydrofuran (THF), yielded sublimable dark-red crystals of composition U(C5H5)3C1. Unlike the ionic cyclopentadienides of the lanthanide rare earth series, the actinide compound did not react in THF with FeCI2 to form ferrocene. Other chemical and physical properties showed that covalent bonding rather than ionic bonding is important. For example, the absorption spectra of the lanthanide cyclopentadienides in THF show very sharp

Chemical form of iron dispersed in the glassy carbon

Abstract: The polycondensed resin from acetylferrocene and furfural was heated up to 400°C in vacuum. The chemical form of iron, which vas liberated by destruction of the ferrocene skeleton, was examined by IR, ESR, Mossbauer spectroscopy and electron microscopy and from magnetic property. The results indicate iron in the carbon network may be in isolated atomic form.

Mass spectrometry of 1,1′-diacetylferrocene and 1,1′-dipropionylferrocene: Evidence for intraannular interaction between alkanoyl substituents

Abstract: The mass spectra of 1,1′-diacetylferrocene, 1,1′-dipropionyl ferrocene and their deuterium and Fe57 isotope labeled analogs are herein reported and discussed. Fragmentation pathways are established and evidence is presented that in the process of fragmentation there is extensive interaction between substituents on the two ferrocene rings. This process apparently has little precedent in the mass spectrometry of ferrocene derivatives. Specifically, the experimental results suggest the simultaneous elimination of two molecules of carbon monoxide, or in another case, of carbon monoxide and ethylene from ions produced in the mass spectrometry of the above compounds.

Compositie propellants with a difunctional ballistic modifier curing agent

Abstract: Disclosed is the liquid, olefinic ferrocene derivative derived from vinyl magnesium chloride and diacetyl ferrocene, which derivative can be co-cured with hydroxy terminated polybutadiene polymers (HTPB) to yield a polymeric binder system for propellants having a chemically bound ballistic modifier as an integral part of the binder. The ferrocene derivative is a difunctional compound having two hydroxyl groups per molecule. Curing of the HTPB and the dihydroxy-ferrocene compound is accomplished by diisocyanates which is added in sufficient quantity so that all the hydroxyl groups of the HTPB and the ferrocene derivative are reacted.

Rearrangements of ferrocenylcarbonium ions by a novel inter-cation exchange mechanism

Abstract: In CF3CO2H solution, α-substituted 2-ferrocenyl-2-propyl cations rearrange to a mixture of the isomeric β- and 1′-substituted cations in the presence of catalytic amounts of ferrocene or an alkylferrocene, by means of an equilibrium-controlled transfer of the (Me2C+) group between cations, ferrocene or an alkyl derivative functioning as transport agent.