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Abstract:Hydride and cyanide addition to a series of di-and polycyclopentadienyliron arene complex cations with etheric bridges is described. Reaction of the di-iron complexes with sodium borohydride resulted in the formation of a number of adducts. p-Methyl-and o,o-dimethylphenoxybenzene cyclopentadienyliron complexes were used as models in this study to allow for the characterization of the analagous di-iron complexes. The use of HH COSY and CH COSY NMR techniques enabled us to identify the isomeric nature of these adducts. The hydride addition results indicated that the etheric substituent had the predominant effect over the methyl group, leading to a higher addition ratio to the meta-, followed by the ortho-, then the para-positions. It was also clear that in the di-iron system, the hydride addition to each complexed arene ring took place independently. The addition of the cyanide anion to di-and poly-iron arene systems was more selective than that of the hydride anion. Reaction of sodium cyanide with p-methyl-or o-methyl-substituted arene complexes led to the formation of one adduct, with the cyanide being added to the meta position to the etheric bridges. However, cyanide addition to the di-iron complex, with a methyl substituent attached at the meta position of each complexed arene, led to the formation of a mixture of adducts. Cyanide addition to the poly-iron system withp-substituted arenes proved to be very selective, allowing for the formation of one adduct.Oxidative demetallation with 2,3-dichloro-5,6-dicyano-1.4-benzoquinone (DDQ) produced the uncomplexed polyaromatic ethers with cyano groups in a very good yield. des Cthers polyaromatiques non complexCs portant des groupes cyano.

Nucleophilic aromatic substitution of cyclopentadienyliron complexes of chloroarenes with oxygen-containing nucleophiles led to the isolation of a number of aromatic ether complexes (2, 5a − e) in very good yields. Reactions of these complexes with 1-naphthol, followed by removal of the cyclopentadienyliron moieties produced aromatic ether compounds with terminal naphthoxy groups (3, 7a − e). Polymerization of these monomers in the presence of ferric chloride gave the poly(aryl ethers) 4 and 8a − e. These materials were obtained with weight-average molecular weights up to 139 900 g/mol. Thermogravimetric analysis of the poly(aryl ethers) showed that these materials displayed no significant weight loss until 458−575 °C. The glass transition temperatures for these polymers ranged from 147 to 226 °C, as measured by differential scanning calorimetry.

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