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The Mossbauer parameters of a series of ferrocene derivatives has been determined. The isomer shift values were independent from the nature of the substituent on the cyclopentadiene ring. The difference in the quadrupole splitting values served informations on the changes caused by the substituents in the electronic structure of the iron central atom. The Mossbauer parameters were interpreted on the basis of MOLCAO-SCF calculations of Shustorovich and Dyatkina. Our results were found in better accord with these than with the analogous calculations of Dhal and Ballhausen.

The catalytic activity of the [Rh(cod)Cl]2 complex (cod cis, cis-cyclo-octa-1,5-diene) with respect to the polymerization of ethynylferrocene (EFc) was examined. A good yield (about 80%) of polyethynylferrocene (PEFc) was obtained in benzene by addition of sodium hydroxide as co-catalyst. PEFc was insoluble in most organic solvents. The conductivity (s) of the undoped polymer is about 10−11 ohm−1 cm−1; upon doping PEFc with iodine in tetrahydrofuran the conductivity can be increased to 10-100 ohm−1 cm−1. The influence of other doping agents was also examined.

The values of the heat capacities of the ferrocene, acetyl-, 1,1′-diacetyl-, benzoyl- and 1,1′-dibenzoylferrocene have been obtained by DSC in the temperature range 20–100°C and the regression line equations in this temperature interval have been calculated. The data obtained for ferrocene agree with those reported in the literature and obtained by Jons and Gjaldbaek. Some observations and correlations on the behaviour of the heat capacities are reported.

Ubersicht uber Aquotisierung, Solvolyse, Isomerisierung und Anionenaustausch, ihren experimentellen Methoden und Einflus vom Oxidationszustand und Grose des Metalls.

The products formed in the base hydrolysis of cis- and trans-[Coen2(OCOCH3)2]ClO4 have been separated by means of paper and column ion-exchange chromatography. The elution patterns and the absorption spectra have shown the presence of cis- and trans-Coen2(OH)OCOCH3+, as intermediates mediates of the hydrolysis reaction. The isomeric configuration of such intermediates remains the same as that of the original compound, while in acid medium the intermediate trans-form isomerizes to the cis form.

The TG, DTG and DSC curves in air and nitrogen and the related thermogravimetric and calorimetric data of the polymers obtained by polymerization of para - and meta -diethynylbenzene and 2,6-diethynylpyridine are reported and discussed. The conductivity properties of these polymers were studied as a function of the residual solvent content (as determined by TG analysis).

Previous studies indicate that some perylene bisimide derivatives can drive the assembly of DNA G-quadruplexes, thus suggesting the possible advantage in the adoption of perylene-conjugated G-rich oligonucleotides in biological and biotechnological applications. Nevertheless, the typical poor solubility of perylene bisimides strongly limits the number of suitable chemical strategies to prepare perylene-conjugated oligonucleotides. In order to overcome these difficulties, we employed the earlier described core twisted perylene derivatives possessing unique optical and electronic properties, besides good solubility in common solvents. As a first result, the large-scale synthesis of a new dibromoperylene derivative (PEOEBr) phosphoramidite building block is herein reported. Furthermore, the structural behavior of the conjugated PEOEBr-GGGTTAGGG (HTRp2) human telomeric repeat was investigated by using CD, UV, fluorescence, and gel electrophoresis techniques in desalted water and in K(+)- and Na(+)-containing buffers. We observed that the peculiar property of PEOEBr moieties to form dimers instead of extended aggregates drives the HTRp2 strands toward dimerization and mainly promotes the formation of quadruplex species having both the 5'-ends located at the same side of the structures. However, the counterions present in solutions (K(+) or Na(+)) as well as the strand concentration, also contribute to influence the topology and the stoichiometry of formed structures. Furthermore, unlike the unmodified sequence GGGTTAGGG (HTR2), HTRp2 strands quickly associate into G-quadruplexes even in desalted water, as assessed by CD experiments.