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A series of novel monodisperse, structurally well defined vinylene‐linked phenothiazine oligomers containing up to 7 phenothiazine units have been designed and synthesized by Heck reaction and McMurry reaction with a convergent approach. These conjugated oligomers showed a progressive bathochromic shift of the absorption maxima and high fluorescence quantum yields in solutions. Notably, the oligomers without strong donor and acceptor units exhibit two‐photon absorption properties, and the two‐photon absorption cross sections (δ) increase with the number of covalently linked phenothiazine units, and δ reaches up to 2071 GM for the one with 7 phenothiazine units at 800 nm. The oligomers might be used as models to study structure–property relationship for their corresponding polymers or applied in organic electronic materials. [ABSTRACT FROM AUTHOR]

Abstract: Four new well-defined monodisperse linear oligofluorenes with anthracene core An-OFVn (n =1–4) have been synthesized through Heck and Wittig reaction. These conjugated oligomers exhibit good solubility in common organic solvents. It is found that the conjugation length of the oligomers can be extended and the formation of excimers can be suppressed with increasing the number of fluorene–vinylene units linked in the 9,10-positions of anthracene. [Copyright &y& Elsevier]

Abstract: Novel monodisperse linear 3,9-linked oligocarbazoles (OCAs) were prepared stepwise using Ullmann coupling reaction in seal-tubes. The resulting OCAs were soluble in common organic solvents. The UV–vis spectra of OCAs exhibited small red shift and their intensities increased linearly with the increase of the carbazole moieties, suggesting that no intramolecular π-interactions appeared at ⩽8-mer. All the OCAs gave strong fluorescence and it was found that the conjugated degree of linear OCAs would be saturated when the number of carbazole units reaches four. [Copyright &y& Elsevier]