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In this work, the preparations of N‐phenyl substituted polybenzimidazoles by direct polycondensation between N‐phenyl substituted aromatic tetramine, 4,6‐di(N‐phenylamine)‐1,3‐diaminebenzene, and dicarboxylic acids in Eaton's reagent are reported. It is shown that the factors of concentration and temperature are very important for synthesis of soluble linear polymer structures. The high temperatures promote strong crosslinking reactions resulting in insoluble gel fraction. Only decreasing the reaction temperature to 90 °C it is possible to obtained soluble polymer of high molecular weights with inherent viscosity of 1.6 dL/g. Although the FTIR and 1H NMR analyses demonstrated incomplete cyclization of thus obtained polymers, but they are readily soluble in organic solvents and the good quality films were prepared by solution casting. In order to complete the cyclization films were undergone by thermal treatment at 320 °C during 1 h. The N‐phenyl substituted polybenzimidazoles demonstrated good thermal and mechanical properties, which were compared to their analog unsubstituted polybenzimidazoles obtained from 1,2,4,5‐Benzenetetramine tetra‐hydrochloride using similar synthetic conditions.

Highly conjugated perinones were evaluated as proligands with [Ru(η 6 -arene)Cl 2 ] 2 precursors (arene = p-cymene or benzene). None of them, except itaco-perinone (IP) bearing one exocyclic methylene group, were able to form coordination compounds. Expected η 1 -coordination through the lone pair of the nitrogen or oxygen atoms of the perinone did not occur. Instead a deprotonation reaction involving the exocyclic methylene was observed and the corresponding [Ru(η 6 -arene)- [a] 3494 (η 3 -IP)Cl] complex was isolated in moderate yields. Mechanistic studies revealed that the base-promoted isomerization of itacoperinone to citraco-perinone prevented higher yields in the synthesis of the allylic complexes. Additionally, it was observed that IP can dimerize through the exocyclic methylene group, indicating high reactivity of this carbon-carbon double bond. Electronic absorption and emission properties of the perinones and organometallic compounds were studied.

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