2,3-Bis(4-fluorobenzoyl)naphthalene was synthesized, and poly(aryl ether)s were prepared through a reaction with various bisphenols in the solvent N,N-dimethylacetamide in the presence of potassium carbonate. Through a reaction with hydrazine or benzylamine, the corresponding benzo[g]phthalazine or benz[g]isoquinoline was formed. The conversion into heterocyclic structures resulted in a significant straightening of the chains, and the glass-transition temperatures, inherent viscosities, and apparent molecular weights from size exclusion chromatography were significantly increased, whereas the solubilities decreased. The diketone-containing polymers were colorless, and the benzo[g]phthalazine- and benz[g]isoquinoline-containing polymers were yellow. The diketone polymers showed strong UV absorption maxima up to 350 nm, with fluorescence emission maxima around 475 nm. The heterocyclic polymers had broad absorptions up to around 450 nm, with strong emission maxima around 550 nm. (C) 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5745-5753, 2004.